Minor update

First implementation of longer result history

.dockerignore

@@ -3,3 +3,4 @@ Dockerfile
 .github
 .idea
 .git
+web/app

.github/codecov.yml

@@ -0,0 +1,6 @@
+ignore:
+  - "watchdog/watchdog.go"
+
+coverage:
+  status:
+    patch: off

.github/workflows/build.yml

@@ -15,16 +15,18 @@ jobs:
     timeout-minutes: 5
     steps:
       - name: Set up Go 1.15
-        uses: actions/setup-go@v1
+        uses: actions/setup-go@v2
         with:
           go-version: 1.15
-        id: go
       - name: Check out code into the Go module directory
         uses: actions/checkout@v2
       - name: Build binary to make sure it works
         run: go build -mod vendor
       - name: Test
-        run: sudo go test -mod vendor ./... -race -coverprofile=coverage.txt -covermode=atomic
+        # We're using "sudo" because one of the tests leverages ping, which requires super-user privileges.
+        # As for the 'env "PATH=$PATH" "GOROOT=$GOROOT"', we need it to use the same "go" executable that
+        # was configured by the "Set up Go 1.15" step (otherwise, it'd use sudo's "go" executable)
+        run: sudo env "PATH=$PATH" "GOROOT=$GOROOT" go test -mod vendor ./... -race -coverprofile=coverage.txt -covermode=atomic
       - name: Codecov
         uses: codecov/codecov-action@v1.0.14
         with:

.gitignore

@@ -1,3 +1,4 @@
-bin
 .idea
 .vscode
+gatus
+db.db

Dockerfile

@@ -13,7 +13,7 @@ RUN CGO_ENABLED=0 GOOS=linux go build -mod vendor -a -installsuffix cgo -o gatus
 FROM scratch
 COPY --from=builder /app/gatus .
 COPY --from=builder /app/config.yaml ./config/config.yaml
-COPY --from=builder /app/static static/
+COPY --from=builder /app/web/static ./web/static
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
 ENV PORT=8080
 EXPOSE ${PORT}

Makefile

@@ -0,0 +1,14 @@
+docker-build:
+	docker build -t twinproduction/gatus:latest .
+
+docker-build-and-run:
+	docker build -t twinproduction/gatus:latest . && docker run -p 8080:8080 --name gatus twinproduction/gatus:latest
+
+build-frontend:
+	npm --prefix web/app run build
+
+run-frontend:
+	npm --prefix web/app run serve
+
+test:
+	go test ./alerting/... ./client/... ./config/... ./controller/... ./core/... ./jsonpath/... ./pattern/... ./security/... ./storage/... ./util/... ./watchdog/... -cover

alerting/provider/custom/custom.go

@@ -2,9 +2,11 @@ package custom
 
 import (
 	"bytes"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"net/http"
+	"os"
 	"strings"
 
 	"github.com/TwinProduction/gatus/client"
@@ -14,11 +16,12 @@ import (
 // AlertProvider is the configuration necessary for sending an alert using a custom HTTP request
 // Technically, all alert providers should be reachable using the custom alert provider
 type AlertProvider struct {
-	URL      string            `yaml:"url"`
-	Method   string            `yaml:"method,omitempty"`
-	Insecure bool              `yaml:"insecure,omitempty"`
-	Body     string            `yaml:"body,omitempty"`
-	Headers  map[string]string `yaml:"headers,omitempty"`
+	URL          string                       `yaml:"url"`
+	Method       string                       `yaml:"method,omitempty"`
+	Insecure     bool                         `yaml:"insecure,omitempty"`
+	Body         string                       `yaml:"body,omitempty"`
+	Headers      map[string]string            `yaml:"headers,omitempty"`
+	Placeholders map[string]map[string]string `yaml:"placeholders,omitempty"`
 }
 
 // IsValid returns whether the provider's configuration is valid
@@ -31,10 +34,25 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
 	return provider
 }
 
+// GetAlertStatePlaceholderValue returns the Placeholder value for ALERT_TRIGGERED_OR_RESOLVED if configured
+func (provider *AlertProvider) GetAlertStatePlaceholderValue(resolved bool) string {
+	status := "TRIGGERED"
+	if resolved {
+		status = "RESOLVED"
+	}
+	if _, ok := provider.Placeholders["ALERT_TRIGGERED_OR_RESOLVED"]; ok {
+		if val, ok := provider.Placeholders["ALERT_TRIGGERED_OR_RESOLVED"][status]; ok {
+			return val
+		}
+	}
+	return status
+}
+
 func (provider *AlertProvider) buildHTTPRequest(serviceName, alertDescription string, resolved bool) *http.Request {
 	body := provider.Body
 	providerURL := provider.URL
 	method := provider.Method
+
 	if strings.Contains(body, "[ALERT_DESCRIPTION]") {
 		body = strings.ReplaceAll(body, "[ALERT_DESCRIPTION]", alertDescription)
 	}
@@ -43,9 +61,9 @@ func (provider *AlertProvider) buildHTTPRequest(serviceName, alertDescription st
 	}
 	if strings.Contains(body, "[ALERT_TRIGGERED_OR_RESOLVED]") {
 		if resolved {
-			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", "RESOLVED")
+			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(true))
 		} else {
-			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", "TRIGGERED")
+			body = strings.ReplaceAll(body, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(false))
 		}
 	}
 	if strings.Contains(providerURL, "[ALERT_DESCRIPTION]") {
@@ -56,9 +74,9 @@ func (provider *AlertProvider) buildHTTPRequest(serviceName, alertDescription st
 	}
 	if strings.Contains(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]") {
 		if resolved {
-			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", "RESOLVED")
+			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(true))
 		} else {
-			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", "TRIGGERED")
+			providerURL = strings.ReplaceAll(providerURL, "[ALERT_TRIGGERED_OR_RESOLVED]", provider.GetAlertStatePlaceholderValue(false))
 		}
 	}
 	if len(method) == 0 {
@@ -74,6 +92,12 @@ func (provider *AlertProvider) buildHTTPRequest(serviceName, alertDescription st
 
 // Send a request to the alert provider and return the body
 func (provider *AlertProvider) Send(serviceName, alertDescription string, resolved bool) ([]byte, error) {
+	if os.Getenv("MOCK_ALERT_PROVIDER") == "true" {
+		if os.Getenv("MOCK_ALERT_PROVIDER_ERROR") == "true" {
+			return nil, errors.New("error")
+		}
+		return []byte("{}"), nil
+	}
 	request := provider.buildHTTPRequest(serviceName, alertDescription, resolved)
 	response, err := client.GetHTTPClient(provider.Insecure).Do(request)
 	if err != nil {

alerting/provider/custom/custom_test.go

@@ -62,9 +62,49 @@ func TestAlertProvider_ToCustomAlertProvider(t *testing.T) {
 	provider := AlertProvider{URL: "http://example.com"}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
-	if customAlertProvider != customAlertProvider {
-		t.Error("customAlertProvider should've been equal to customAlertProvider")
+	if customAlertProvider.URL != "http://example.com" {
+		t.Error("expected URL to be http://example.com, got", customAlertProvider.URL)
+	}
+}
+
+func TestAlertProvider_buildHTTPRequestWithCustomPlaceholder(t *testing.T) {
+	const (
+		ExpectedURL  = "http://example.com/service-name?event=test&description=alert-description"
+		ExpectedBody = "service-name,alert-description,test"
+	)
+	customAlertProvider := &AlertProvider{
+		URL:     "http://example.com/[SERVICE_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
+		Body:    "[SERVICE_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
+		Headers: nil,
+		Placeholders: map[string]map[string]string{
+			"ALERT_TRIGGERED_OR_RESOLVED": {
+				"RESOLVED": "test",
+			},
+		},
+	}
+	request := customAlertProvider.buildHTTPRequest("service-name", "alert-description", true)
+	if request.URL.String() != ExpectedURL {
+		t.Error("expected URL to be", ExpectedURL, "was", request.URL.String())
+	}
+	body, _ := ioutil.ReadAll(request.Body)
+	if string(body) != ExpectedBody {
+		t.Error("expected body to be", ExpectedBody, "was", string(body))
+	}
+}
+
+func TestAlertProvider_GetAlertStatePlaceholderValueDefaults(t *testing.T) {
+	customAlertProvider := &AlertProvider{
+		URL:          "http://example.com/[SERVICE_NAME]?event=[ALERT_TRIGGERED_OR_RESOLVED]&description=[ALERT_DESCRIPTION]",
+		Body:         "[SERVICE_NAME],[ALERT_DESCRIPTION],[ALERT_TRIGGERED_OR_RESOLVED]",
+		Headers:      nil,
+		Placeholders: nil,
+	}
+	if customAlertProvider.GetAlertStatePlaceholderValue(true) != "RESOLVED" {
+		t.Error("expected RESOLVED, got", customAlertProvider.GetAlertStatePlaceholderValue(true))
+	}
+	if customAlertProvider.GetAlertStatePlaceholderValue(false) != "TRIGGERED" {
+		t.Error("expected TRIGGERED, got", customAlertProvider.GetAlertStatePlaceholderValue(false))
 	}
 }

alerting/provider/mattermost/mattermost.go

@@ -38,7 +38,7 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
 		} else {
 			prefix = ":x:"
 		}
-		results += fmt.Sprintf("%s - `%s`\n", prefix, conditionResult.Condition)
+		results += fmt.Sprintf("%s - `%s`\\n", prefix, conditionResult.Condition)
 	}
 	return &custom.AlertProvider{
 		URL:      provider.WebhookURL,

alerting/provider/mattermost/mattermost_test.go

@@ -1,6 +1,8 @@
 package mattermost
 
 import (
+	"encoding/json"
+	"net/http"
 	"strings"
 	"testing"
 
@@ -19,23 +21,45 @@ func TestAlertProvider_IsValid(t *testing.T) {
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.com"}
+	provider := AlertProvider{WebhookURL: "http://example.org"}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "resolved") {
 		t.Error("customAlertProvider.Body should've contained the substring resolved")
 	}
+	if customAlertProvider.URL != "http://example.org" {
+		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
-	provider := AlertProvider{WebhookURL: "http://example.com"}
+	provider := AlertProvider{WebhookURL: "http://example.org"}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "triggered") {
 		t.Error("customAlertProvider.Body should've contained the substring triggered")
 	}
+	if customAlertProvider.URL != "http://example.org" {
+		t.Errorf("expected URL to be %s, got %s", "http://example.org", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
 }

alerting/provider/messagebird/messagebird_test.go

@@ -1,6 +1,8 @@
 package messagebird
 
 import (
+	"encoding/json"
+	"net/http"
 	"strings"
 	"testing"
 
@@ -30,11 +32,22 @@ func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
 	}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "RESOLVED") {
 		t.Error("customAlertProvider.Body should've contained the substring RESOLVED")
 	}
+	if customAlertProvider.URL != "https://rest.messagebird.com/messages" {
+		t.Errorf("expected URL to be %s, got %s", "https://rest.messagebird.com/messages", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
@@ -45,9 +58,20 @@ func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
 	}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "TRIGGERED") {
 		t.Error("customAlertProvider.Body should've contained the substring TRIGGERED")
 	}
+	if customAlertProvider.URL != "https://rest.messagebird.com/messages" {
+		t.Errorf("expected URL to be %s, got %s", "https://rest.messagebird.com/messages", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
 }

alerting/provider/pagerduty/pagerduty_test.go

@@ -1,6 +1,8 @@
 package pagerduty
 
 import (
+	"encoding/json"
+	"net/http"
 	"strings"
 	"testing"
 
@@ -22,20 +24,42 @@ func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
 	provider := AlertProvider{IntegrationKey: "00000000000000000000000000000000"}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "RESOLVED") {
 		t.Error("customAlertProvider.Body should've contained the substring RESOLVED")
 	}
+	if customAlertProvider.URL != "https://events.pagerduty.com/v2/enqueue" {
+		t.Errorf("expected URL to be %s, got %s", "https://events.pagerduty.com/v2/enqueue", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
 	provider := AlertProvider{IntegrationKey: "00000000000000000000000000000000"}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "TRIGGERED") {
 		t.Error("customAlertProvider.Body should've contained the substring TRIGGERED")
 	}
+	if customAlertProvider.URL != "https://events.pagerduty.com/v2/enqueue" {
+		t.Errorf("expected URL to be %s, got %s", "https://events.pagerduty.com/v2/enqueue", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
 }

alerting/provider/slack/slack.go

@@ -31,11 +31,11 @@ func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, aler
 	for _, conditionResult := range result.ConditionResults {
 		var prefix string
 		if conditionResult.Success {
-			prefix = ":heavy_check_mark:"
+			prefix = ":white_check_mark:"
 		} else {
 			prefix = ":x:"
 		}
-		results += fmt.Sprintf("%s - `%s`\n", prefix, conditionResult.Condition)
+		results += fmt.Sprintf("%s - `%s`\\n", prefix, conditionResult.Condition)
 	}
 	return &custom.AlertProvider{
 		URL:    provider.WebhookURL,

alerting/provider/slack/slack_test.go

@@ -1,6 +1,8 @@
 package slack
 
 import (
+	"encoding/json"
+	"net/http"
 	"strings"
 	"testing"
 
@@ -22,20 +24,42 @@ func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
 	provider := AlertProvider{WebhookURL: "http://example.com"}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "SUCCESSFUL_CONDITION", Success: true}}}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "resolved") {
 		t.Error("customAlertProvider.Body should've contained the substring resolved")
 	}
+	if customAlertProvider.URL != "http://example.com" {
+		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
 	provider := AlertProvider{WebhookURL: "http://example.com"}
 	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{ConditionResults: []*core.ConditionResult{{Condition: "UNSUCCESSFUL_CONDITION", Success: false}}}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "triggered") {
 		t.Error("customAlertProvider.Body should've contained the substring triggered")
 	}
+	if customAlertProvider.URL != "http://example.com" {
+		t.Errorf("expected URL to be %s, got %s", "http://example.com", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	body := make(map[string]interface{})
+	err := json.Unmarshal([]byte(customAlertProvider.Body), &body)
+	if err != nil {
+		t.Error("expected body to be valid JSON, got error:", err.Error())
+	}
 }

alerting/provider/twilio/twilio_test.go

@@ -1,6 +1,7 @@
 package twilio
 
 import (
+	"net/http"
 	"strings"
 	"testing"
 
@@ -26,31 +27,49 @@ func TestTwilioAlertProvider_IsValid(t *testing.T) {
 func TestAlertProvider_ToCustomAlertProviderWithResolvedAlert(t *testing.T) {
 	provider := AlertProvider{
 		SID:   "1",
-		Token: "1",
-		From:  "1",
-		To:    "1",
+		Token: "2",
+		From:  "3",
+		To:    "4",
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, true)
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{Name: "service-name"}, &core.Alert{Description: "alert-description"}, &core.Result{}, true)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "RESOLVED") {
 		t.Error("customAlertProvider.Body should've contained the substring RESOLVED")
 	}
+	if customAlertProvider.URL != "https://api.twilio.com/2010-04-01/Accounts/1/Messages.json" {
+		t.Errorf("expected URL to be %s, got %s", "https://api.twilio.com/2010-04-01/Accounts/1/Messages.json", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	if customAlertProvider.Body != "Body=RESOLVED%3A+service-name+-+alert-description&From=3&To=4" {
+		t.Errorf("expected body to be %s, got %s", "Body=RESOLVED%3A+service-name+-+alert-description&From=3&To=4", customAlertProvider.Body)
+	}
 }
 
 func TestAlertProvider_ToCustomAlertProviderWithTriggeredAlert(t *testing.T) {
 	provider := AlertProvider{
-		SID:   "1",
-		Token: "1",
-		From:  "1",
+		SID:   "4",
+		Token: "3",
+		From:  "2",
 		To:    "1",
 	}
-	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{}, &core.Alert{}, &core.Result{}, false)
+	customAlertProvider := provider.ToCustomAlertProvider(&core.Service{Name: "service-name"}, &core.Alert{Description: "alert-description"}, &core.Result{}, false)
 	if customAlertProvider == nil {
-		t.Error("customAlertProvider shouldn't have been nil")
+		t.Fatal("customAlertProvider shouldn't have been nil")
 	}
 	if !strings.Contains(customAlertProvider.Body, "TRIGGERED") {
 		t.Error("customAlertProvider.Body should've contained the substring TRIGGERED")
 	}
+	if customAlertProvider.URL != "https://api.twilio.com/2010-04-01/Accounts/4/Messages.json" {
+		t.Errorf("expected URL to be %s, got %s", "https://api.twilio.com/2010-04-01/Accounts/4/Messages.json", customAlertProvider.URL)
+	}
+	if customAlertProvider.Method != http.MethodPost {
+		t.Errorf("expected method to be %s, got %s", http.MethodPost, customAlertProvider.Method)
+	}
+	if customAlertProvider.Body != "Body=TRIGGERED%3A+service-name+-+alert-description&From=2&To=1" {
+		t.Errorf("expected body to be %s, got %s", "Body=TRIGGERED%3A+service-name+-+alert-description&From=2&To=1", customAlertProvider.Body)
+	}
 }

client/client.go

@@ -12,6 +12,10 @@ import (
 var (
 	secureHTTPClient   *http.Client
 	insecureHTTPClient *http.Client
+
+	// pingTimeout is the timeout for the Ping function
+	// This is mainly exposed for testing purposes
+	pingTimeout = 5 * time.Second
 )
 
 // GetHTTPClient returns the shared HTTP client
@@ -19,10 +23,11 @@ func GetHTTPClient(insecure bool) *http.Client {
 	if insecure {
 		if insecureHTTPClient == nil {
 			insecureHTTPClient = &http.Client{
-				Timeout: time.Second * 10,
+				Timeout: 10 * time.Second,
 				Transport: &http.Transport{
 					MaxIdleConns:        100,
 					MaxIdleConnsPerHost: 20,
+					Proxy:               http.ProxyFromEnvironment,
 					TLSClientConfig: &tls.Config{
 						InsecureSkipVerify: true,
 					},
@@ -37,6 +42,7 @@ func GetHTTPClient(insecure bool) *http.Client {
 			Transport: &http.Transport{
 				MaxIdleConns:        100,
 				MaxIdleConnsPerHost: 20,
+				Proxy:               http.ProxyFromEnvironment,
 			},
 		}
 	}
@@ -62,7 +68,7 @@ func Ping(address string) (bool, time.Duration) {
 		return false, 0
 	}
 	pinger.Count = 1
-	pinger.Timeout = 5 * time.Second
+	pinger.Timeout = pingTimeout
 	pinger.SetNetwork("ip4")
 	pinger.SetPrivileged(true)
 	err = pinger.Run()
@@ -70,6 +76,10 @@ func Ping(address string) (bool, time.Duration) {
 		return false, 0
 	}
 	if pinger.Statistics() != nil {
+		// If the packet loss is 100, it means that the packet didn't reach the host
+		if pinger.Statistics().PacketLoss == 100 {
+			return false, pinger.Timeout
+		}
 		return true, pinger.Statistics().MaxRtt
 	}
 	return true, 0

client/client_test.go

@@ -2,6 +2,7 @@ package client
 
 import (
 	"testing"
+	"time"
 )
 
 func TestGetHTTPClient(t *testing.T) {
@@ -28,6 +29,7 @@ func TestGetHTTPClient(t *testing.T) {
 }
 
 func TestPing(t *testing.T) {
+	pingTimeout = 500 * time.Millisecond
 	if success, rtt := Ping("127.0.0.1"); !success {
 		t.Error("expected true")
 		if rtt == 0 {
@@ -35,7 +37,13 @@ func TestPing(t *testing.T) {
 		}
 	}
 	if success, rtt := Ping("256.256.256.256"); success {
-		t.Error("expected false")
+		t.Error("expected false, because the IP is invalid")
+		if rtt != 0 {
+			t.Error("Round-trip time returned on failure should've been 0")
+		}
+	}
+	if success, rtt := Ping("192.168.152.153"); success {
+		t.Error("expected false, because the IP is valid but the host should be unreachable")
 		if rtt != 0 {
 			t.Error("Round-trip time returned on failure should've been 0")
 		}

config.yaml

@@ -1,14 +1,14 @@
 services:
-  - name: frontend
+  - name: front-end
     group: core
     url: "https://twinnation.org/health"
     interval: 1m
     conditions:
       - "[STATUS] == 200"
       - "[BODY].status == UP"
-      - "[RESPONSE_TIME] < 1000"
+      - "[RESPONSE_TIME] < 150"
 
-  - name: backend
+  - name: back-end
     group: core
     url: "http://example.org/"
     interval: 5m

config/config.go

@@ -11,6 +11,8 @@ import (
 	"github.com/TwinProduction/gatus/core"
 	"github.com/TwinProduction/gatus/k8s"
 	"github.com/TwinProduction/gatus/security"
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/util"
 	"gopkg.in/yaml.v2"
 )
 
@@ -28,9 +30,6 @@ const (
 
 	// DefaultPort is the default port the service will listen on
 	DefaultPort = 8080
-
-	// DefaultContextRoot is the default context root of the web application
-	DefaultContextRoot = "/"
 )
 
 var (
@@ -74,8 +73,11 @@ type Config struct {
 	// Kubernetes is the Kubernetes configuration
 	Kubernetes *k8s.Config `yaml:"kubernetes"`
 
+	// Storage is the configuration for how the data is stored
+	Storage *storage.Config `yaml:"storage"`
+
 	// Web is the configuration for the web listener
-	Web *webConfig `yaml:"web"`
+	Web *WebConfig `yaml:"web"`
 }
 
 // Get returns the configuration, or panics if the configuration hasn't loaded yet
@@ -86,6 +88,12 @@ func Get() *Config {
 	return config
 }
 
+// Set sets the configuration
+// Used only for testing
+func Set(cfg *Config) {
+	config = cfg
+}
+
 // Load loads a custom configuration file
 // Note that the misconfiguration of some fields may lead to panics. This is on purpose.
 func Load(configFile string) error {
@@ -141,13 +149,33 @@ func parseAndValidateConfigBytes(yamlBytes []byte) (config *Config, err error) {
 		validateServicesConfig(config)
 		validateKubernetesConfig(config)
 		validateWebConfig(config)
+		validateStorageConfig(config)
 	}
 	return
 }
 
+func validateStorageConfig(config *Config) {
+	if config.Storage == nil {
+		config.Storage = &storage.Config{}
+	}
+	err := storage.Initialize(config.Storage)
+	if err != nil {
+		panic(err)
+	}
+	// Remove all ServiceStatus that represent services which no longer exist in the configuration
+	var keys []string
+	for _, service := range config.Services {
+		keys = append(keys, util.ConvertGroupAndServiceToKey(service.Group, service.Name))
+	}
+	numberOfServiceStatusesDeleted := storage.Get().DeleteAllServiceStatusesNotInKeys(keys)
+	if numberOfServiceStatusesDeleted > 0 {
+		log.Printf("[config][validateStorageConfig] Deleted %d service statuses because their matching services no longer existed", numberOfServiceStatusesDeleted)
+	}
+}
+
 func validateWebConfig(config *Config) {
 	if config.Web == nil {
-		config.Web = &webConfig{Address: DefaultAddress, Port: DefaultPort, ContextRoot: DefaultContextRoot}
+		config.Web = &WebConfig{Address: DefaultAddress, Port: DefaultPort}
 	} else {
 		config.Web.validateAndSetDefaults()
 	}

config/config_test.go

@@ -17,6 +17,16 @@ func TestGetBeforeConfigIsLoaded(t *testing.T) {
 	t.Fatal("Should've panicked because the configuration hasn't been loaded yet")
 }
 
+func TestSet(t *testing.T) {
+	if config != nil {
+		t.Fatal("config should've been nil")
+	}
+	Set(&Config{})
+	if config == nil {
+		t.Fatal("config shouldn't have been nil")
+	}
+}
+
 func TestLoadFileThatDoesNotExist(t *testing.T) {
 	err := Load("file-that-does-not-exist.yaml")
 	if err == nil {
@@ -32,7 +42,10 @@ func TestLoadDefaultConfigurationFile(t *testing.T) {
 }
 
 func TestParseAndValidateConfigBytes(t *testing.T) {
-	config, err := parseAndValidateConfigBytes([]byte(`
+	file := t.TempDir() + "/test.db"
+	config, err := parseAndValidateConfigBytes([]byte(fmt.Sprintf(`
+storage:
+  file: %s
 services:
   - name: twinnation
     url: https://twinnation.org/health
@@ -44,9 +57,9 @@ services:
     conditions:
       - "[STATUS] != 400"
       - "[STATUS] != 500"
-`))
+`, file)))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -89,7 +102,7 @@ services:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -109,9 +122,6 @@ services:
 	if config.Web.Port != DefaultPort {
 		t.Errorf("Port should have been %d, because it is the default value", DefaultPort)
 	}
-	if config.Web.ContextRoot != DefaultContextRoot {
-		t.Errorf("ContextRoot should have been %s, because it is the default value", DefaultContextRoot)
-	}
 }
 
 func TestParseAndValidateConfigBytesWithAddress(t *testing.T) {
@@ -125,7 +135,7 @@ services:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -155,12 +165,12 @@ web:
   port: 12345
 services:
   - name: twinnation
-    url: https://twinnation.org/actuator/health
+    url: https://twinnation.org/health
     conditions:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -168,17 +178,15 @@ services:
 	if config.Metrics {
 		t.Error("Metrics should've been false by default")
 	}
-	if config.Services[0].URL != "https://twinnation.org/actuator/health" {
-		t.Errorf("URL should have been %s", "https://twinnation.org/actuator/health")
+	if config.Services[0].URL != "https://twinnation.org/health" {
+		t.Errorf("URL should have been %s", "https://twinnation.org/health")
 	}
 	if config.Services[0].Interval != 60*time.Second {
 		t.Errorf("Interval should have been %s, because it is the default value", 60*time.Second)
 	}
-
 	if config.Web.Address != DefaultAddress {
 		t.Errorf("Bind address should have been %s, because it is the default value", DefaultAddress)
 	}
-
 	if config.Web.Port != 12345 {
 		t.Errorf("Port should have been %d, because it is specified in config", 12345)
 	}
@@ -196,7 +204,7 @@ services:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -218,44 +226,6 @@ services:
 	}
 }
 
-func TestParseAndValidateConfigBytesWithPortAndHostAndContextRoot(t *testing.T) {
-	config, err := parseAndValidateConfigBytes([]byte(`
-web:
-  port: 12345
-  address: 127.0.0.1
-  context-root: /deeply/nested/down=/their
-services:
-  - name: twinnation
-    url: https://twinnation.org/health
-    conditions:
-      - "[STATUS] == 200"
-`))
-	if err != nil {
-		t.Error("No error should've been returned")
-	}
-	if config == nil {
-		t.Fatal("Config shouldn't have been nil")
-	}
-	if config.Metrics {
-		t.Error("Metrics should've been false by default")
-	}
-	if config.Services[0].URL != "https://twinnation.org/health" {
-		t.Errorf("URL should have been %s", "https://twinnation.org/health")
-	}
-	if config.Services[0].Interval != 60*time.Second {
-		t.Errorf("Interval should have been %s, because it is the default value", 60*time.Second)
-	}
-	if config.Web.Address != "127.0.0.1" {
-		t.Errorf("Bind address should have been %s, because it is specified in config", "127.0.0.1")
-	}
-	if config.Web.Port != 12345 {
-		t.Errorf("Port should have been %d, because it is specified in config", 12345)
-	}
-	if config.Web.ContextRoot != "/deeply/nested/down=/their/" {
-		t.Errorf("Port should have been %s, because it is specified in config", "/deeply/nested/down=/their/")
-	}
-}
-
 func TestParseAndValidateConfigBytesWithInvalidPort(t *testing.T) {
 	defer func() { recover() }()
 	_, _ = parseAndValidateConfigBytes([]byte(`
@@ -271,17 +241,19 @@ services:
 	t.Fatal("Should've panicked because the configuration specifies an invalid port value")
 }
 
-func TestParseAndValidateConfigBytesWithMetrics(t *testing.T) {
+func TestParseAndValidateConfigBytesWithMetricsAndCustomUserAgentHeader(t *testing.T) {
 	config, err := parseAndValidateConfigBytes([]byte(`
 metrics: true
 services:
   - name: twinnation
     url: https://twinnation.org/health
+    headers:
+      User-Agent: Test/2.0
     conditions:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -301,25 +273,25 @@ services:
 	if config.Web.Port != DefaultPort {
 		t.Errorf("Port should have been %d, because it is the default value", DefaultPort)
 	}
-	if config.Web.ContextRoot != DefaultContextRoot {
-		t.Errorf("ContextRoot should have been %s, because it is the default value", DefaultContextRoot)
+	if userAgent := config.Services[0].Headers["User-Agent"]; userAgent != "Test/2.0" {
+		t.Errorf("User-Agent should've been %s, got %s", "Test/2.0", userAgent)
 	}
 }
 
 func TestParseAndValidateConfigBytesWithMetricsAndHostAndPort(t *testing.T) {
 	config, err := parseAndValidateConfigBytes([]byte(`
 metrics: true
+web:
+  address: 192.168.0.1
+  port: 9090
 services:
   - name: twinnation
     url: https://twinnation.org/health
     conditions:
       - "[STATUS] == 200"
-web:
-  address: 192.168.0.1
-  port: 9090
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -327,17 +299,20 @@ web:
 	if !config.Metrics {
 		t.Error("Metrics should have been true")
 	}
+	if config.Web.Address != "192.168.0.1" {
+		t.Errorf("Bind address should have been %s, because it is the default value", "192.168.0.1")
+	}
+	if config.Web.Port != 9090 {
+		t.Errorf("Port should have been %d, because it is specified in config", 9090)
+	}
 	if config.Services[0].URL != "https://twinnation.org/health" {
 		t.Errorf("URL should have been %s", "https://twinnation.org/health")
 	}
 	if config.Services[0].Interval != 60*time.Second {
 		t.Errorf("Interval should have been %s, because it is the default value", 60*time.Second)
 	}
-	if config.Web.Address != "192.168.0.1" {
-		t.Errorf("Bind address should have been %s, because it is the default value", "192.168.0.1")
-	}
-	if config.Web.Port != 9090 {
-		t.Errorf("Port should have been %d, because it is specified in config", 9090)
+	if userAgent := config.Services[0].Headers["User-Agent"]; userAgent != core.GatusUserAgent {
+		t.Errorf("User-Agent should've been %s because it's the default value, got %s", core.GatusUserAgent, userAgent)
 	}
 }
 
@@ -360,7 +335,6 @@ badconfig:
 func TestParseAndValidateConfigBytesWithAlerting(t *testing.T) {
 	config, err := parseAndValidateConfigBytes([]byte(`
 debug: true
-
 alerting:
   slack:
     webhook-url: "http://example.com"
@@ -387,7 +361,7 @@ services:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -480,7 +454,7 @@ services:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -514,7 +488,7 @@ services:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -528,11 +502,106 @@ services:
 	if !config.Alerting.Custom.IsValid() {
 		t.Fatal("Custom alerting config should've been valid")
 	}
+	if config.Alerting.Custom.GetAlertStatePlaceholderValue(true) != "RESOLVED" {
+		t.Fatal("ALERT_TRIGGERED_OR_RESOLVED placeholder value for RESOLVED should've been 'RESOLVED', got", config.Alerting.Custom.GetAlertStatePlaceholderValue(true))
+	}
+	if config.Alerting.Custom.GetAlertStatePlaceholderValue(false) != "TRIGGERED" {
+		t.Fatal("ALERT_TRIGGERED_OR_RESOLVED placeholder value for TRIGGERED should've been 'TRIGGERED', got", config.Alerting.Custom.GetAlertStatePlaceholderValue(false))
+	}
 	if config.Alerting.Custom.Insecure {
 		t.Fatal("config.Alerting.Custom.Insecure shouldn't have been true")
 	}
 }
 
+func TestParseAndValidateConfigBytesWithCustomAlertingConfigAndCustomPlaceholderValues(t *testing.T) {
+	config, err := parseAndValidateConfigBytes([]byte(`
+alerting:
+  custom:
+    placeholders:
+      ALERT_TRIGGERED_OR_RESOLVED:
+        TRIGGERED: "partial_outage"
+        RESOLVED: "operational"
+    url: "https://example.com"
+    insecure: true
+    body: "[ALERT_TRIGGERED_OR_RESOLVED]: [SERVICE_NAME] - [ALERT_DESCRIPTION]"
+services:
+  - name: twinnation
+    url: https://twinnation.org/health
+    alerts:
+      - type: custom
+    conditions:
+      - "[STATUS] == 200"
+`))
+	if err != nil {
+		t.Error("expected no error, got", err.Error())
+	}
+	if config == nil {
+		t.Fatal("Config shouldn't have been nil")
+	}
+	if config.Alerting == nil {
+		t.Fatal("config.Alerting shouldn't have been nil")
+	}
+	if config.Alerting.Custom == nil {
+		t.Fatal("PagerDuty alerting config shouldn't have been nil")
+	}
+	if !config.Alerting.Custom.IsValid() {
+		t.Fatal("Custom alerting config should've been valid")
+	}
+	if config.Alerting.Custom.GetAlertStatePlaceholderValue(true) != "operational" {
+		t.Fatal("ALERT_TRIGGERED_OR_RESOLVED placeholder value for RESOLVED should've been 'operational'")
+	}
+	if config.Alerting.Custom.GetAlertStatePlaceholderValue(false) != "partial_outage" {
+		t.Fatal("ALERT_TRIGGERED_OR_RESOLVED placeholder value for TRIGGERED should've been 'partial_outage'")
+	}
+	if !config.Alerting.Custom.Insecure {
+		t.Fatal("config.Alerting.Custom.Insecure shouldn't have been true")
+	}
+}
+
+func TestParseAndValidateConfigBytesWithCustomAlertingConfigAndOneCustomPlaceholderValue(t *testing.T) {
+	config, err := parseAndValidateConfigBytes([]byte(`
+alerting:
+  custom:
+    placeholders:
+      ALERT_TRIGGERED_OR_RESOLVED:
+        TRIGGERED: "partial_outage"
+    url: "https://example.com"
+    insecure: true
+    body: "[ALERT_TRIGGERED_OR_RESOLVED]: [SERVICE_NAME] - [ALERT_DESCRIPTION]"
+services:
+  - name: twinnation
+    url: https://twinnation.org/health
+    alerts:
+      - type: custom
+    conditions:
+      - "[STATUS] == 200"
+`))
+	if err != nil {
+		t.Error("expected no error, got", err.Error())
+	}
+	if config == nil {
+		t.Fatal("Config shouldn't have been nil")
+	}
+	if config.Alerting == nil {
+		t.Fatal("config.Alerting shouldn't have been nil")
+	}
+	if config.Alerting.Custom == nil {
+		t.Fatal("PagerDuty alerting config shouldn't have been nil")
+	}
+	if !config.Alerting.Custom.IsValid() {
+		t.Fatal("Custom alerting config should've been valid")
+	}
+	if config.Alerting.Custom.GetAlertStatePlaceholderValue(true) != "RESOLVED" {
+		t.Fatal("ALERT_TRIGGERED_OR_RESOLVED placeholder value for RESOLVED should've been 'RESOLVED'")
+	}
+	if config.Alerting.Custom.GetAlertStatePlaceholderValue(false) != "partial_outage" {
+		t.Fatal("ALERT_TRIGGERED_OR_RESOLVED placeholder value for TRIGGERED should've been 'partial_outage'")
+	}
+	if !config.Alerting.Custom.Insecure {
+		t.Fatal("config.Alerting.Custom.Insecure shouldn't have been true")
+	}
+}
+
 func TestParseAndValidateConfigBytesWithCustomAlertingConfigThatHasInsecureSetToTrue(t *testing.T) {
 	config, err := parseAndValidateConfigBytes([]byte(`
 alerting:
@@ -553,7 +622,7 @@ services:
       - "[STATUS] == 200"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -606,7 +675,7 @@ services:
       - "[STATUS] == 200"
 `, expectedUsername, expectedPasswordHash)))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")
@@ -673,7 +742,7 @@ kubernetes:
       target-path: "/health"
 `))
 	if err != nil {
-		t.Error("No error should've been returned")
+		t.Error("expected no error, got", err.Error())
 	}
 	if config == nil {
 		t.Fatal("Config shouldn't have been nil")

config/web.go

@@ -3,25 +3,20 @@ package config
 import (
 	"fmt"
 	"math"
-	"net/url"
-	"strings"
 )
 
-// webConfig is the structure which supports the configuration of the endpoint
+// WebConfig is the structure which supports the configuration of the endpoint
 // which provides access to the web frontend
-type webConfig struct {
+type WebConfig struct {
 	// Address to listen on (defaults to 0.0.0.0 specified by DefaultAddress)
 	Address string `yaml:"address"`
 
 	// Port to listen on (default to 8080 specified by DefaultPort)
 	Port int `yaml:"port"`
-
-	// ContextRoot set the root context for the web application
-	ContextRoot string `yaml:"context-root"`
 }
 
 // validateAndSetDefaults checks and sets the default values for fields that are not set
-func (web *webConfig) validateAndSetDefaults() {
+func (web *WebConfig) validateAndSetDefaults() {
 	// Validate the Address
 	if len(web.Address) == 0 {
 		web.Address = DefaultAddress
@@ -32,32 +27,9 @@ func (web *webConfig) validateAndSetDefaults() {
 	} else if web.Port < 0 || web.Port > math.MaxUint16 {
 		panic(fmt.Sprintf("invalid port: value should be between %d and %d", 0, math.MaxUint16))
 	}
-	// Validate the ContextRoot
-	if len(web.ContextRoot) == 0 {
-		web.ContextRoot = DefaultContextRoot
-	} else {
-		trimmedContextRoot := strings.Trim(web.ContextRoot, "/")
-		if len(trimmedContextRoot) == 0 {
-			web.ContextRoot = DefaultContextRoot
-			return
-		}
-		rootContextURL, err := url.Parse(trimmedContextRoot)
-		if err != nil {
-			panic("invalid context root:" + err.Error())
-		}
-		if rootContextURL.Path != trimmedContextRoot {
-			panic("invalid context root: too complex")
-		}
-		web.ContextRoot = "/" + strings.Trim(rootContextURL.Path, "/") + "/"
-	}
 }
 
 // SocketAddress returns the combination of the Address and the Port
-func (web *webConfig) SocketAddress() string {
+func (web *WebConfig) SocketAddress() string {
 	return fmt.Sprintf("%s:%d", web.Address, web.Port)
 }
-
-// PrependWithContextRoot appends the given path to the ContextRoot
-func (web *webConfig) PrependWithContextRoot(path string) string {
-	return web.ContextRoot + strings.Trim(path, "/")
-}

config/web_test.go

@@ -1,12 +1,11 @@
 package config
 
 import (
-	"fmt"
 	"testing"
 )
 
 func TestWebConfig_SocketAddress(t *testing.T) {
-	web := &webConfig{
+	web := &WebConfig{
 		Address: "0.0.0.0",
 		Port:    8081,
 	}
@@ -14,86 +13,3 @@ func TestWebConfig_SocketAddress(t *testing.T) {
 		t.Errorf("expected %s, got %s", "0.0.0.0:8081", web.SocketAddress())
 	}
 }
-
-func TestWebConfig_PrependWithContextRoot(t *testing.T) {
-	web := &webConfig{ContextRoot: "/status/"}
-	if result := web.PrependWithContextRoot("/api/v1/results"); result != "/status/api/v1/results" {
-		t.Errorf("expected %s, got %s", "/status/api/v1/results", result)
-	}
-	if result := web.PrependWithContextRoot("/health"); result != "/status/health" {
-		t.Errorf("expected %s, got %s", "/status/health", result)
-	}
-	if result := web.PrependWithContextRoot("/health/"); result != "/status/health" {
-		t.Errorf("expected %s, got %s", "/status/health", result)
-	}
-}
-
-// validContextRootTest specifies all test case which should end up in
-// a valid context root used to bind the web interface to
-var validContextRootTests = []struct {
-	name         string
-	path         string
-	expectedPath string
-}{
-	{"Empty", "", "/"},
-	{"/", "/", "/"},
-	{"///", "///", "/"},
-	{"Single character 'a'", "a", "/a/"},
-	{"Slash at the beginning", "/status", "/status/"},
-	{"Slashes at start and end", "/status/", "/status/"},
-	{"Multiple slashes at start", "//status", "/status/"},
-	{"Multiple slashes at start and end", "///status////", "/status/"},
-	{"Contains '@' in path'", "me@/status/gatus", "/me@/status/gatus/"},
-	{"Nested context with trailing slash", "/status/gatus/", "/status/gatus/"},
-	{"Nested context without trailing slash", "/status/gatus/system", "/status/gatus/system/"},
-}
-
-func TestWebConfig_ValidContextRoots(t *testing.T) {
-	for idx, test := range validContextRootTests {
-		t.Run(fmt.Sprintf("%d: %s", idx, test.name), func(t *testing.T) {
-			expectValidResultForContextRoot(t, test.path, test.expectedPath)
-		})
-	}
-}
-
-func expectValidResultForContextRoot(t *testing.T, path string, expected string) {
-	web := &webConfig{
-		ContextRoot: path,
-	}
-	web.validateAndSetDefaults()
-	if web.ContextRoot != expected {
-		t.Errorf("expected %s, got %s", expected, web.ContextRoot)
-	}
-}
-
-// invalidContextRootTests contains all tests for context root which are
-// expected to fail and stop program execution
-var invalidContextRootTests = []struct {
-	name string
-	path string
-}{
-	{"Only a fragment identifier", "#"},
-	{"Invalid character in path", "/invalid" + string([]byte{0x7F})},
-	{"Starts with protocol", "http://status/gatus"},
-	{"Path with fragment", "/status/gatus#here"},
-	{"Starts with '://'", "://status"},
-	{"Contains query parameter", "/status/h?ello=world"},
-	{"Contains '?'", "/status?"},
-}
-
-func TestWebConfig_InvalidContextRoots(t *testing.T) {
-	for idx, test := range invalidContextRootTests {
-		t.Run(fmt.Sprintf("%d: %s", idx, test.name), func(t *testing.T) {
-			expectInvalidResultForContextRoot(t, test.path)
-		})
-	}
-}
-
-func expectInvalidResultForContextRoot(t *testing.T, path string) {
-	defer func() { recover() }()
-
-	web := &webConfig{ContextRoot: path}
-	web.validateAndSetDefaults()
-
-	t.Fatal(fmt.Sprintf("Should've panicked because the configuration specifies an invalid context root: %s", path))
-}

controller/badge.go

@@ -0,0 +1,105 @@
+package controller
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+	"time"
+
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/gorilla/mux"
+)
+
+// badgeHandler handles the automatic generation of badge based on the group name and service name passed.
+//
+// Valid values for {duration}: 7d, 24h, 1h
+// Pattern for {identifier}: <KEY>.svg
+func badgeHandler(writer http.ResponseWriter, request *http.Request) {
+	variables := mux.Vars(request)
+	duration := variables["duration"]
+	if duration != "7d" && duration != "24h" && duration != "1h" {
+		writer.WriteHeader(http.StatusBadRequest)
+		_, _ = writer.Write([]byte("Durations supported: 7d, 24h, 1h"))
+		return
+	}
+	identifier := variables["identifier"]
+	key := strings.TrimSuffix(identifier, ".svg")
+	serviceStatus := storage.Get().GetServiceStatusByKey(key)
+	if serviceStatus == nil {
+		writer.WriteHeader(http.StatusNotFound)
+		_, _ = writer.Write([]byte("Requested service not found"))
+		return
+	}
+	if serviceStatus.Uptime == nil {
+		writer.WriteHeader(http.StatusInternalServerError)
+		_, _ = writer.Write([]byte("Failed to compute uptime"))
+		return
+	}
+	formattedDate := time.Now().Format(http.TimeFormat)
+	writer.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
+	writer.Header().Set("Date", formattedDate)
+	writer.Header().Set("Expires", formattedDate)
+	writer.Header().Set("Content-Type", "image/svg+xml")
+	_, _ = writer.Write(generateSVG(duration, serviceStatus.Uptime))
+}
+
+func generateSVG(duration string, uptime *core.Uptime) []byte {
+	var labelWidth, valueWidth, valueWidthAdjustment int
+	var color string
+	var value float64
+	switch duration {
+	case "7d":
+		labelWidth = 65
+		value = uptime.LastSevenDays
+	case "24h":
+		labelWidth = 70
+		value = uptime.LastTwentyFourHours
+	case "1h":
+		labelWidth = 65
+		value = uptime.LastHour
+	default:
+	}
+	if value >= 0.8 {
+		color = "#40cc11"
+	} else {
+		color = "#c7130a"
+	}
+	sanitizedValue := strings.TrimRight(strings.TrimRight(fmt.Sprintf("%.2f", value*100), "0"), ".") + "%"
+	if strings.Contains(sanitizedValue, ".") {
+		valueWidthAdjustment = -10
+	}
+	valueWidth = (len(sanitizedValue) * 11) + valueWidthAdjustment
+	width := labelWidth + valueWidth
+	labelX := labelWidth / 2
+	valueX := labelWidth + (valueWidth / 2)
+	svg := []byte(fmt.Sprintf(`<svg xmlns="http://www.w3.org/2000/svg" width="%d" height="20">
+  <linearGradient id="b" x2="0" y2="100%%">
+    <stop offset="0" stop-color="#bbb" stop-opacity=".1"/>
+    <stop offset="1" stop-opacity=".1"/>
+  </linearGradient>
+  <mask id="a">
+    <rect width="%d" height="20" rx="3" fill="#fff"/>
+  </mask>
+  <g mask="url(#a)">
+    <path fill="#555" d="M0 0h%dv20H0z"/>
+    <path fill="%s" d="M%d 0h%dv20H%dz"/>
+    <path fill="url(#b)" d="M0 0h%dv20H0z"/>
+  </g>
+  <g fill="#fff" text-anchor="middle" font-family="DejaVu Sans,Verdana,Geneva,sans-serif" font-size="11">
+    <text x="%d" y="15" fill="#010101" fill-opacity=".3">
+      uptime %s
+    </text>
+    <text x="%d" y="14">
+      uptime %s
+    </text>
+    <text x="%d" y="15" fill="#010101" fill-opacity=".3">
+      %s
+    </text>
+    <text x="%d" y="14">
+      %s
+    </text>
+  </g>
+</svg>`, width, width, labelWidth, color, labelWidth, valueWidth, labelWidth, width, labelX, duration, labelX, duration, valueX, sanitizedValue, valueX, sanitizedValue))
+	return svg
+}

controller/controller.go

@@ -0,0 +1,171 @@
+package controller
+
+import (
+	"bytes"
+	"compress/gzip"
+	"context"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/security"
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gocache"
+	"github.com/TwinProduction/health"
+	"github.com/gorilla/mux"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+const (
+	cacheTTL = 10 * time.Second
+)
+
+var (
+	cache = gocache.NewCache().WithMaxSize(100).WithEvictionPolicy(gocache.LeastRecentlyUsed)
+
+	// staticFolder is the path to the location of the static folder from the root path of the project
+	// The only reason this is exposed is to allow running tests from a different path than the root path of the project
+	staticFolder = "./web/static"
+
+	// server is the http.Server created by Handle.
+	// The only reason it exists is for testing purposes.
+	server *http.Server
+)
+
+func init() {
+	if err := cache.StartJanitor(); err != nil {
+		log.Fatal("[controller][init] Failed to start cache janitor:", err.Error())
+	}
+}
+
+// Handle creates the router and starts the server
+func Handle() {
+	cfg := config.Get()
+	var router http.Handler = CreateRouter(cfg)
+	if os.Getenv("ENVIRONMENT") == "dev" {
+		router = developmentCorsHandler(router)
+	}
+	server = &http.Server{
+		Addr:         fmt.Sprintf("%s:%d", cfg.Web.Address, cfg.Web.Port),
+		Handler:      router,
+		ReadTimeout:  15 * time.Second,
+		WriteTimeout: 15 * time.Second,
+		IdleTimeout:  15 * time.Second,
+	}
+	log.Println("[controller][Handle] Listening on " + cfg.Web.SocketAddress())
+	if os.Getenv("ROUTER_TEST") == "true" {
+		return
+	}
+	log.Println("[controller][Handle]", server.ListenAndServe())
+}
+
+// Shutdown stops the server
+func Shutdown() {
+	if server != nil {
+		_ = server.Shutdown(context.TODO())
+		server = nil
+	}
+}
+
+// CreateRouter creates the router for the http server
+func CreateRouter(cfg *config.Config) *mux.Router {
+	router := mux.NewRouter()
+	if cfg.Metrics {
+		router.Handle("/metrics", promhttp.Handler()).Methods("GET")
+	}
+	router.Handle("/health", health.Handler().WithJSON(true)).Methods("GET")
+	router.HandleFunc("/favicon.ico", favIconHandler).Methods("GET")
+	router.HandleFunc("/api/v1/statuses", secureIfNecessary(cfg, serviceStatusesHandler)).Methods("GET") // No GzipHandler for this one, because we cache the content
+	router.HandleFunc("/api/v1/statuses/{key}", secureIfNecessary(cfg, GzipHandlerFunc(serviceStatusHandler))).Methods("GET")
+	router.HandleFunc("/api/v1/badges/uptime/{duration}/{identifier}", badgeHandler).Methods("GET")
+	// SPA
+	router.HandleFunc("/services/{service}", spaHandler).Methods("GET")
+	// Everything else falls back on static content
+	router.PathPrefix("/").Handler(GzipHandler(http.FileServer(http.Dir(staticFolder))))
+	return router
+}
+
+func secureIfNecessary(cfg *config.Config, handler http.HandlerFunc) http.HandlerFunc {
+	if cfg.Security != nil && cfg.Security.IsValid() {
+		return security.Handler(handler, cfg.Security)
+	}
+	return handler
+}
+
+// serviceStatusesHandler handles requests to retrieve all service statuses
+// Due to the size of the response, this function leverages a cache.
+// Must not be wrapped by GzipHandler
+func serviceStatusesHandler(writer http.ResponseWriter, r *http.Request) {
+	page, pageSize := extractPageAndPageSizeFromRequest(r)
+	gzipped := strings.Contains(r.Header.Get("Accept-Encoding"), "gzip")
+	var exists bool
+	var value interface{}
+	if gzipped {
+		writer.Header().Set("Content-Encoding", "gzip")
+		value, exists = cache.Get(fmt.Sprintf("service-status-%d-%d-gzipped", page, pageSize))
+	} else {
+		value, exists = cache.Get(fmt.Sprintf("service-status-%d-%d", page, pageSize))
+	}
+	var data []byte
+	if !exists {
+		var err error
+		buffer := &bytes.Buffer{}
+		gzipWriter := gzip.NewWriter(buffer)
+		data, err = json.Marshal(storage.Get().GetAllServiceStatusesWithResultPagination(page, pageSize))
+		if err != nil {
+			log.Printf("[controller][serviceStatusesHandler] Unable to marshal object to JSON: %s", err.Error())
+			writer.WriteHeader(http.StatusInternalServerError)
+			_, _ = writer.Write([]byte("Unable to marshal object to JSON"))
+			return
+		}
+		_, _ = gzipWriter.Write(data)
+		_ = gzipWriter.Close()
+		gzippedData := buffer.Bytes()
+		cache.SetWithTTL(fmt.Sprintf("service-status-%d-%d", page, pageSize), data, cacheTTL)
+		cache.SetWithTTL(fmt.Sprintf("service-status-%d-%d-gzipped", page, pageSize), gzippedData, cacheTTL)
+		if gzipped {
+			data = gzippedData
+		}
+	} else {
+		data = value.([]byte)
+	}
+	writer.Header().Add("Content-Type", "application/json")
+	writer.WriteHeader(http.StatusOK)
+	_, _ = writer.Write(data)
+}
+
+// serviceStatusHandler retrieves a single ServiceStatus by group name and service name
+func serviceStatusHandler(writer http.ResponseWriter, r *http.Request) {
+	page, pageSize := extractPageAndPageSizeFromRequest(r)
+	vars := mux.Vars(r)
+	serviceStatus := storage.Get().GetServiceStatusByKey(vars["key"])
+	if serviceStatus == nil {
+		log.Printf("[controller][serviceStatusHandler] Service with key=%s not found", vars["key"])
+		writer.WriteHeader(http.StatusNotFound)
+		_, _ = writer.Write([]byte("not found"))
+		return
+	}
+	data := map[string]interface{}{
+		"serviceStatus": serviceStatus.WithResultPagination(page, pageSize),
+		// The following fields, while present on core.ServiceStatus, are annotated to remain hidden so that we can
+		// expose only the necessary data on /api/v1/statuses.
+		// Since the /api/v1/statuses/{key} endpoint does need this data, however, we explicitly expose it here
+		"events": serviceStatus.Events,
+		"uptime": serviceStatus.Uptime,
+	}
+	output, err := json.Marshal(data)
+	if err != nil {
+		log.Printf("[controller][serviceStatusHandler] Unable to marshal object to JSON: %s", err.Error())
+		writer.WriteHeader(http.StatusInternalServerError)
+		_, _ = writer.Write([]byte("unable to marshal object to JSON"))
+		return
+	}
+	writer.Header().Add("Content-Type", "application/json")
+	writer.WriteHeader(http.StatusOK)
+	_, _ = writer.Write(output)
+}

controller/controller_test.go

@@ -0,0 +1,333 @@
+package controller
+
+import (
+	"math/rand"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/TwinProduction/gatus/config"
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage"
+	"github.com/TwinProduction/gatus/watchdog"
+)
+
+var (
+	firstCondition  = core.Condition("[STATUS] == 200")
+	secondCondition = core.Condition("[RESPONSE_TIME] < 500")
+	thirdCondition  = core.Condition("[CERTIFICATE_EXPIRATION] < 72h")
+
+	timestamp = time.Now()
+
+	testService = core.Service{
+		Name:                    "name",
+		Group:                   "group",
+		URL:                     "https://example.org/what/ever",
+		Method:                  "GET",
+		Body:                    "body",
+		Interval:                30 * time.Second,
+		Conditions:              []*core.Condition{&firstCondition, &secondCondition, &thirdCondition},
+		Alerts:                  nil,
+		Insecure:                false,
+		NumberOfFailuresInARow:  0,
+		NumberOfSuccessesInARow: 0,
+	}
+	testSuccessfulResult = core.Result{
+		Hostname:              "example.org",
+		IP:                    "127.0.0.1",
+		HTTPStatus:            200,
+		Body:                  []byte("body"),
+		Errors:                nil,
+		Connected:             true,
+		Success:               true,
+		Timestamp:             timestamp,
+		Duration:              150 * time.Millisecond,
+		CertificateExpiration: 10 * time.Hour,
+		ConditionResults: []*core.ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   true,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   true,
+			},
+		},
+	}
+	testUnsuccessfulResult = core.Result{
+		Hostname:              "example.org",
+		IP:                    "127.0.0.1",
+		HTTPStatus:            200,
+		Body:                  []byte("body"),
+		Errors:                []string{"error-1", "error-2"},
+		Connected:             true,
+		Success:               false,
+		Timestamp:             timestamp,
+		Duration:              750 * time.Millisecond,
+		CertificateExpiration: 10 * time.Hour,
+		ConditionResults: []*core.ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   false,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   false,
+			},
+		},
+	}
+)
+
+func TestCreateRouter(t *testing.T) {
+	defer storage.Get().Clear()
+	defer cache.Clear()
+	staticFolder = "../web/static"
+	cfg := &config.Config{
+		Metrics: true,
+		Services: []*core.Service{
+			{
+				Name:  "frontend",
+				Group: "core",
+			},
+			{
+				Name:  "backend",
+				Group: "core",
+			},
+		},
+	}
+	watchdog.UpdateServiceStatuses(cfg.Services[0], &core.Result{Success: true, Duration: time.Millisecond, Timestamp: time.Now()})
+	watchdog.UpdateServiceStatuses(cfg.Services[1], &core.Result{Success: false, Duration: time.Second, Timestamp: time.Now()})
+	router := CreateRouter(cfg)
+	type Scenario struct {
+		Name         string
+		Path         string
+		ExpectedCode int
+		Gzip         bool
+	}
+	scenarios := []Scenario{
+		{
+			Name:         "health",
+			Path:         "/health",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "metrics",
+			Path:         "/metrics",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badges-1h",
+			Path:         "/api/v1/badges/uptime/1h/core_frontend.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badges-24h",
+			Path:         "/api/v1/badges/uptime/24h/core_backend.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badges-7d",
+			Path:         "/api/v1/badges/uptime/7d/core_frontend.svg",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "badges-with-invalid-duration",
+			Path:         "/api/v1/badges/uptime/3d/core_backend.svg",
+			ExpectedCode: http.StatusBadRequest,
+		},
+		{
+			Name:         "badges-for-invalid-key",
+			Path:         "/api/v1/badges/uptime/7d/invalid_key.svg",
+			ExpectedCode: http.StatusNotFound,
+		},
+		{
+			Name:         "service-statuses",
+			Path:         "/api/v1/statuses",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "service-statuses-gzip",
+			Path:         "/api/v1/statuses",
+			ExpectedCode: http.StatusOK,
+			Gzip:         true,
+		},
+		{
+			Name:         "service-statuses-pagination",
+			Path:         "/api/v1/statuses?page=1&pageSize=20",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "service-status",
+			Path:         "/api/v1/statuses/core_frontend",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "service-status-gzip",
+			Path:         "/api/v1/statuses/core_frontend",
+			ExpectedCode: http.StatusOK,
+			Gzip:         true,
+		},
+		{
+			Name:         "service-status-for-invalid-key",
+			Path:         "/api/v1/statuses/invalid_key",
+			ExpectedCode: http.StatusNotFound,
+		},
+		{
+			Name:         "favicon",
+			Path:         "/favicon.ico",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "frontend-home",
+			Path:         "/",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "frontend-assets",
+			Path:         "/js/app.js",
+			ExpectedCode: http.StatusOK,
+		},
+		{
+			Name:         "frontend-service",
+			Path:         "/services/core_frontend",
+			ExpectedCode: http.StatusOK,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			if scenario.Gzip {
+				request.Header.Set("Accept-Encoding", "gzip")
+			}
+			responseRecorder := httptest.NewRecorder()
+			router.ServeHTTP(responseRecorder, request)
+			if responseRecorder.Code != scenario.ExpectedCode {
+				t.Errorf("%s %s should have returned %d, but returned %d instead", request.Method, request.URL, scenario.ExpectedCode, responseRecorder.Code)
+			}
+		})
+	}
+}
+
+func TestHandle(t *testing.T) {
+	defer storage.Get().Clear()
+	defer cache.Clear()
+	cfg := &config.Config{
+		Web: &config.WebConfig{
+			Address: "0.0.0.0",
+			Port:    rand.Intn(65534),
+		},
+		Services: []*core.Service{
+			{
+				Name:  "frontend",
+				Group: "core",
+			},
+			{
+				Name:  "backend",
+				Group: "core",
+			},
+		},
+	}
+	config.Set(cfg)
+	defer config.Set(nil)
+	_ = os.Setenv("ROUTER_TEST", "true")
+	_ = os.Setenv("ENVIRONMENT", "dev")
+	defer os.Clearenv()
+	Handle()
+	defer Shutdown()
+	request, _ := http.NewRequest("GET", "/health", nil)
+	responseRecorder := httptest.NewRecorder()
+	server.Handler.ServeHTTP(responseRecorder, request)
+	if responseRecorder.Code != http.StatusOK {
+		t.Error("expected GET /health to return status code 200")
+	}
+	if server == nil {
+		t.Fatal("server should've been set (but because we set ROUTER_TEST, it shouldn't have been started)")
+	}
+}
+
+func TestShutdown(t *testing.T) {
+	// Pretend that we called controller.Handle(), which initializes the server variable
+	server = &http.Server{}
+	Shutdown()
+	if server != nil {
+		t.Error("server should've been shut down")
+	}
+}
+
+func TestServiceStatusesHandler(t *testing.T) {
+	defer storage.Get().Clear()
+	defer cache.Clear()
+	staticFolder = "../web/static"
+	firstResult := &testSuccessfulResult
+	secondResult := &testUnsuccessfulResult
+	storage.Get().Insert(&testService, firstResult)
+	storage.Get().Insert(&testService, secondResult)
+	// Can't be bothered dealing with timezone issues on the worker that runs the automated tests
+	firstResult.Timestamp = time.Time{}
+	secondResult.Timestamp = time.Time{}
+	router := CreateRouter(&config.Config{})
+
+	type Scenario struct {
+		Name         string
+		Path         string
+		ExpectedCode int
+		ExpectedBody string
+	}
+	scenarios := []Scenario{
+		{
+			Name:         "no-pagination",
+			Path:         "/api/v1/statuses",
+			ExpectedCode: http.StatusOK,
+			ExpectedBody: `{"group_name":{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"errors":null,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"},{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}]}}`,
+		},
+		{
+			Name:         "pagination-first-result",
+			Path:         "/api/v1/statuses?page=1&pageSize=1",
+			ExpectedCode: http.StatusOK,
+			ExpectedBody: `{"group_name":{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}]}}`,
+		},
+		{
+			Name:         "pagination-second-result",
+			Path:         "/api/v1/statuses?page=2&pageSize=1",
+			ExpectedCode: http.StatusOK,
+			ExpectedBody: `{"group_name":{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"errors":null,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"}]}}`,
+		},
+		{
+			Name:         "pagination-no-results",
+			Path:         "/api/v1/statuses?page=5&pageSize=20",
+			ExpectedCode: http.StatusOK,
+			ExpectedBody: `{"group_name":{"name":"name","group":"group","key":"group_name","results":[]}}`,
+		},
+		{
+			Name:         "invalid-pagination-should-fall-back-to-default",
+			Path:         "/api/v1/statuses?page=INVALID&pageSize=INVALID",
+			ExpectedCode: http.StatusOK,
+			ExpectedBody: `{"group_name":{"name":"name","group":"group","key":"group_name","results":[{"status":200,"hostname":"example.org","duration":150000000,"errors":null,"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":true},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":true}],"success":true,"timestamp":"0001-01-01T00:00:00Z"},{"status":200,"hostname":"example.org","duration":750000000,"errors":["error-1","error-2"],"conditionResults":[{"condition":"[STATUS] == 200","success":true},{"condition":"[RESPONSE_TIME] \u003c 500","success":false},{"condition":"[CERTIFICATE_EXPIRATION] \u003c 72h","success":false}],"success":false,"timestamp":"0001-01-01T00:00:00Z"}]}}`,
+		},
+	}
+
+	for _, scenario := range scenarios {
+		t.Run(scenario.Name, func(t *testing.T) {
+			request, _ := http.NewRequest("GET", scenario.Path, nil)
+			responseRecorder := httptest.NewRecorder()
+			router.ServeHTTP(responseRecorder, request)
+			if responseRecorder.Code != scenario.ExpectedCode {
+				t.Errorf("%s %s should have returned %d, but returned %d instead", request.Method, request.URL, scenario.ExpectedCode, responseRecorder.Code)
+			}
+			output := responseRecorder.Body.String()
+			if output != scenario.ExpectedBody {
+				t.Errorf("expected:\n %s\n\ngot:\n %s", scenario.ExpectedBody, output)
+			}
+		})
+	}
+}

controller/cors.go

@@ -0,0 +1,10 @@
+package controller
+
+import "net/http"
+
+func developmentCorsHandler(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Access-Control-Allow-Origin", "http://localhost:8081")
+		next.ServeHTTP(w, r)
+	})
+}

controller/favicon.go

@@ -0,0 +1,8 @@
+package controller
+
+import "net/http"
+
+// favIconHandler handles requests for /favicon.ico
+func favIconHandler(writer http.ResponseWriter, request *http.Request) {
+	http.ServeFile(writer, request, staticFolder+"/favicon.ico")
+}

controller/gzip.go

@@ -1,4 +1,4 @@
-package main
+package controller
 
 import (
 	"compress/gzip"
@@ -32,10 +32,18 @@ func (w *gzipResponseWriter) Write(b []byte) (int, error) {
 	return w.Writer.Write(b)
 }
 
-// GzipHandler compresses the response of a given handler if the request's headers specify that the client
+// GzipHandler compresses the response of a given http.Handler if the request's headers specify that the client
 // supports gzip encoding
 func GzipHandler(next http.Handler) http.Handler {
-	return http.HandlerFunc(func(writer http.ResponseWriter, r *http.Request) {
+	return GzipHandlerFunc(func(writer http.ResponseWriter, r *http.Request) {
+		next.ServeHTTP(writer, r)
+	})
+}
+
+// GzipHandlerFunc compresses the response of a given http.HandlerFunc if the request's headers specify that the client
+// supports gzip encoding
+func GzipHandlerFunc(next http.HandlerFunc) http.HandlerFunc {
+	return func(writer http.ResponseWriter, r *http.Request) {
 		// If the request doesn't specify that it supports gzip, then don't compress it
 		if !strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
 			next.ServeHTTP(writer, r)
@@ -47,5 +55,5 @@ func GzipHandler(next http.Handler) http.Handler {
 		gz.Reset(writer)
 		defer gz.Close()
 		next.ServeHTTP(&gzipResponseWriter{ResponseWriter: writer, Writer: gz}, r)
-	})
+	}
 }

controller/spa.go

@@ -0,0 +1,8 @@
+package controller
+
+import "net/http"
+
+// spaHandler handles requests for /
+func spaHandler(writer http.ResponseWriter, request *http.Request) {
+	http.ServeFile(writer, request, staticFolder+"/index.html")
+}

controller/util.go

@@ -0,0 +1,46 @@
+package controller
+
+import (
+	"net/http"
+	"strconv"
+)
+
+const (
+	// DefaultPage is the default page to use if none is specified or an invalid value is provided
+	DefaultPage = 1
+
+	// DefaultPageSize is the default page siZE to use if none is specified or an invalid value is provided
+	DefaultPageSize = 20
+
+	// MaximumPageSize is the maximum page size allowed
+	MaximumPageSize = 100
+)
+
+func extractPageAndPageSizeFromRequest(r *http.Request) (page int, pageSize int) {
+	var err error
+	if pageParameter := r.URL.Query().Get("page"); len(pageParameter) == 0 {
+		page = DefaultPage
+	} else {
+		page, err = strconv.Atoi(pageParameter)
+		if err != nil {
+			page = DefaultPage
+		}
+		if page < 1 {
+			page = DefaultPage
+		}
+	}
+	if pageSizeParameter := r.URL.Query().Get("pageSize"); len(pageSizeParameter) == 0 {
+		pageSize = DefaultPageSize
+	} else {
+		pageSize, err = strconv.Atoi(pageSizeParameter)
+		if err != nil {
+			pageSize = DefaultPageSize
+		}
+		if pageSize > MaximumPageSize {
+			pageSize = MaximumPageSize
+		} else if pageSize < 1 {
+			pageSize = DefaultPageSize
+		}
+	}
+	return
+}

controller/util_test.go

@@ -0,0 +1,67 @@
+package controller
+
+import (
+	"fmt"
+	"net/http"
+	"testing"
+)
+
+func TestExtractPageAndPageSizeFromRequest(t *testing.T) {
+	type Scenario struct {
+		Name             string
+		Page             string
+		PageSize         string
+		ExpectedPage     int
+		ExpectedPageSize int
+	}
+	scenarios := []Scenario{
+		{
+			Page:             "1",
+			PageSize:         "20",
+			ExpectedPage:     1,
+			ExpectedPageSize: 20,
+		},
+		{
+			Page:             "2",
+			PageSize:         "10",
+			ExpectedPage:     2,
+			ExpectedPageSize: 10,
+		},
+		{
+			Page:             "2",
+			PageSize:         "10",
+			ExpectedPage:     2,
+			ExpectedPageSize: 10,
+		},
+		{
+			Page:             "1",
+			PageSize:         "999999",
+			ExpectedPage:     1,
+			ExpectedPageSize: MaximumPageSize,
+		},
+		{
+			Page:             "-1",
+			PageSize:         "-1",
+			ExpectedPage:     DefaultPage,
+			ExpectedPageSize: DefaultPageSize,
+		},
+		{
+			Page:             "invalid",
+			PageSize:         "invalid",
+			ExpectedPage:     DefaultPage,
+			ExpectedPageSize: DefaultPageSize,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run("page-"+scenario.Page+"-pageSize-"+scenario.PageSize, func(t *testing.T) {
+			request, _ := http.NewRequest("GET", fmt.Sprintf("/api/v1/statuses?page=%s&pageSize=%s", scenario.Page, scenario.PageSize), nil)
+			actualPage, actualPageSize := extractPageAndPageSizeFromRequest(request)
+			if actualPage != scenario.ExpectedPage {
+				t.Errorf("expected %d, got %d", scenario.ExpectedPage, actualPage)
+			}
+			if actualPageSize != scenario.ExpectedPageSize {
+				t.Errorf("expected %d, got %d", scenario.ExpectedPageSize, actualPageSize)
+			}
+		})
+	}
+}

core/alert.go

@@ -26,6 +26,12 @@ type Alert struct {
 
 	// Triggered is used to determine whether an alert has been triggered. When an alert is resolved, this value
 	// should be set back to false. It is used to prevent the same alert from going out twice.
+	//
+	// This value should only be modified if the provider.AlertProvider's Send function does not return an error for an
+	// alert that hasn't been triggered yet. This doubles as a lazy retry. The reason why this behavior isn't also
+	// applied for alerts that are already triggered and has become "healthy" again is to prevent a case where, for
+	// some reason, the alert provider always returns errors when trying to send the resolved notification
+	// (SendOnResolved).
 	Triggered bool
 }
 

core/condition.go

@@ -2,7 +2,6 @@ package core
 
 import (
 	"fmt"
-	"log"
 	"strconv"
 	"strings"
 	"time"
@@ -48,11 +47,20 @@ const (
 	CertificateExpirationPlaceholder = "[CERTIFICATE_EXPIRATION]"
 
 	// LengthFunctionPrefix is the prefix for the length function
+	//
+	// Usage: len([BODY].articles) == 10, len([BODY].name) > 5
 	LengthFunctionPrefix = "len("
 
 	// PatternFunctionPrefix is the prefix for the pattern function
+	//
+	// Usage: pat(192.168.*.*)
 	PatternFunctionPrefix = "pat("
 
+	// AnyFunctionPrefix is the prefix for the any function
+	//
+	// Usage: any(1.1.1.1, 1.0.0.1)
+	AnyFunctionPrefix = "any("
+
 	// FunctionSuffix is the suffix for all functions
 	FunctionSuffix = ")"
 
@@ -64,51 +72,52 @@ const (
 type Condition string
 
 // evaluate the Condition with the Result of the health check
-func (c *Condition) evaluate(result *Result) bool {
-	condition := string(*c)
+func (c Condition) evaluate(result *Result) bool {
+	condition := string(c)
 	success := false
-	var resolvedCondition string
+	conditionToDisplay := condition
 	if strings.Contains(condition, "==") {
-		parts := sanitizeAndResolve(strings.Split(condition, "=="), result)
-		success = isEqual(parts[0], parts[1])
-		resolvedCondition = fmt.Sprintf("%v == %v", parts[0], parts[1])
+		parameters, resolvedParameters := sanitizeAndResolve(strings.Split(condition, "=="), result)
+		success = isEqual(resolvedParameters[0], resolvedParameters[1])
+		if !success {
+			conditionToDisplay = prettify(parameters, resolvedParameters, "==")
+		}
 	} else if strings.Contains(condition, "!=") {
-		parts := sanitizeAndResolve(strings.Split(condition, "!="), result)
-		success = !isEqual(parts[0], parts[1])
-		resolvedCondition = fmt.Sprintf("%v != %v", parts[0], parts[1])
+		parameters, resolvedParameters := sanitizeAndResolve(strings.Split(condition, "!="), result)
+		success = !isEqual(resolvedParameters[0], resolvedParameters[1])
+		if !success {
+			conditionToDisplay = prettify(parameters, resolvedParameters, "!=")
+		}
 	} else if strings.Contains(condition, "<=") {
-		parts := sanitizeAndResolveNumerical(strings.Split(condition, "<="), result)
-		success = parts[0] <= parts[1]
-		resolvedCondition = fmt.Sprintf("%v <= %v", parts[0], parts[1])
+		parameters, resolvedParameters := sanitizeAndResolveNumerical(strings.Split(condition, "<="), result)
+		success = resolvedParameters[0] <= resolvedParameters[1]
+		if !success {
+			conditionToDisplay = prettifyNumericalParameters(parameters, resolvedParameters, "<=")
+		}
 	} else if strings.Contains(condition, ">=") {
-		parts := sanitizeAndResolveNumerical(strings.Split(condition, ">="), result)
-		success = parts[0] >= parts[1]
-		resolvedCondition = fmt.Sprintf("%v >= %v", parts[0], parts[1])
+		parameters, resolvedParameters := sanitizeAndResolveNumerical(strings.Split(condition, ">="), result)
+		success = resolvedParameters[0] >= resolvedParameters[1]
+		if !success {
+			conditionToDisplay = prettifyNumericalParameters(parameters, resolvedParameters, ">=")
+		}
 	} else if strings.Contains(condition, ">") {
-		parts := sanitizeAndResolveNumerical(strings.Split(condition, ">"), result)
-		success = parts[0] > parts[1]
-		resolvedCondition = fmt.Sprintf("%v > %v", parts[0], parts[1])
+		parameters, resolvedParameters := sanitizeAndResolveNumerical(strings.Split(condition, ">"), result)
+		success = resolvedParameters[0] > resolvedParameters[1]
+		if !success {
+			conditionToDisplay = prettifyNumericalParameters(parameters, resolvedParameters, ">")
+		}
 	} else if strings.Contains(condition, "<") {
-		parts := sanitizeAndResolveNumerical(strings.Split(condition, "<"), result)
-		success = parts[0] < parts[1]
-		resolvedCondition = fmt.Sprintf("%v < %v", parts[0], parts[1])
+		parameters, resolvedParameters := sanitizeAndResolveNumerical(strings.Split(condition, "<"), result)
+		success = resolvedParameters[0] < resolvedParameters[1]
+		if !success {
+			conditionToDisplay = prettifyNumericalParameters(parameters, resolvedParameters, "<")
+		}
 	} else {
 		result.Errors = append(result.Errors, fmt.Sprintf("invalid condition '%s' has been provided", condition))
 		return false
 	}
-	conditionToDisplay := condition
-	// If the condition isn't a success, return what the resolved condition was too
 	if !success {
-		log.Printf("[Condition][evaluate] Condition '%s' did not succeed because '%s' is false", condition, resolvedCondition)
-		// Check if the resolved condition was an invalid path
-		isResolvedConditionInvalidPath := strings.ReplaceAll(resolvedCondition, fmt.Sprintf("%s ", InvalidConditionElementSuffix), "") == condition
-		if isResolvedConditionInvalidPath {
-			// Since, in the event of an invalid path, the resolvedCondition contains the condition itself,
-			// we'll only display the resolvedCondition
-			conditionToDisplay = resolvedCondition
-		} else {
-			conditionToDisplay = fmt.Sprintf("%s (%s)", condition, resolvedCondition)
-		}
+		//log.Printf("[Condition][evaluate] Condition '%s' did not succeed because '%s' is false", condition, condition)
 	}
 	result.ConditionResults = append(result.ConditionResults, &ConditionResult{Condition: conditionToDisplay, Success: success})
 	return success
@@ -116,33 +125,66 @@ func (c *Condition) evaluate(result *Result) bool {
 
 // isEqual compares two strings.
 //
-// It also supports the pattern function. That is to say, if one of the strings starts with PatternFunctionPrefix
-// and ends with FunctionSuffix, it will be treated like a pattern.
+// Supports the pattern and the any functions.
+// i.e. if one of the parameters starts with PatternFunctionPrefix and ends with FunctionSuffix, it will be treated like
+// a pattern.
 func isEqual(first, second string) bool {
-	var isFirstPattern, isSecondPattern bool
-	if strings.HasPrefix(first, PatternFunctionPrefix) && strings.HasSuffix(first, FunctionSuffix) {
-		isFirstPattern = true
-		first = strings.TrimSuffix(strings.TrimPrefix(first, PatternFunctionPrefix), FunctionSuffix)
-	}
-	if strings.HasPrefix(second, PatternFunctionPrefix) && strings.HasSuffix(second, FunctionSuffix) {
-		isSecondPattern = true
-		second = strings.TrimSuffix(strings.TrimPrefix(second, PatternFunctionPrefix), FunctionSuffix)
-	}
-	if isFirstPattern && !isSecondPattern {
-		return pattern.Match(first, second)
-	} else if !isFirstPattern && isSecondPattern {
-		return pattern.Match(second, first)
-	} else {
-		return first == second
+	firstHasFunctionSuffix := strings.HasSuffix(first, FunctionSuffix)
+	secondHasFunctionSuffix := strings.HasSuffix(second, FunctionSuffix)
+	if firstHasFunctionSuffix || secondHasFunctionSuffix {
+		var isFirstPattern, isSecondPattern bool
+		if strings.HasPrefix(first, PatternFunctionPrefix) && firstHasFunctionSuffix {
+			isFirstPattern = true
+			first = strings.TrimSuffix(strings.TrimPrefix(first, PatternFunctionPrefix), FunctionSuffix)
+		}
+		if strings.HasPrefix(second, PatternFunctionPrefix) && secondHasFunctionSuffix {
+			isSecondPattern = true
+			second = strings.TrimSuffix(strings.TrimPrefix(second, PatternFunctionPrefix), FunctionSuffix)
+		}
+		if isFirstPattern && !isSecondPattern {
+			return pattern.Match(first, second)
+		} else if !isFirstPattern && isSecondPattern {
+			return pattern.Match(second, first)
+		}
+		var isFirstAny, isSecondAny bool
+		if strings.HasPrefix(first, AnyFunctionPrefix) && firstHasFunctionSuffix {
+			isFirstAny = true
+			first = strings.TrimSuffix(strings.TrimPrefix(first, AnyFunctionPrefix), FunctionSuffix)
+		}
+		if strings.HasPrefix(second, AnyFunctionPrefix) && secondHasFunctionSuffix {
+			isSecondAny = true
+			second = strings.TrimSuffix(strings.TrimPrefix(second, AnyFunctionPrefix), FunctionSuffix)
+		}
+		if isFirstAny && !isSecondAny {
+			options := strings.Split(first, ",")
+			for _, option := range options {
+				if strings.TrimSpace(option) == second {
+					return true
+				}
+			}
+			return false
+		} else if !isFirstAny && isSecondAny {
+			options := strings.Split(second, ",")
+			for _, option := range options {
+				if strings.TrimSpace(option) == first {
+					return true
+				}
+			}
+			return false
+		}
 	}
+	return first == second
 }
 
-// sanitizeAndResolve sanitizes and resolves a list of element and returns the list of resolved elements
-func sanitizeAndResolve(list []string, result *Result) []string {
-	var sanitizedList []string
+// sanitizeAndResolve sanitizes and resolves a list of elements and returns the list of parameters as well as a list
+// of resolved parameters
+func sanitizeAndResolve(elements []string, result *Result) ([]string, []string) {
+	parameters := make([]string, len(elements))
+	resolvedParameters := make([]string, len(elements))
 	body := strings.TrimSpace(string(result.Body))
-	for _, element := range list {
+	for i, element := range elements {
 		element = strings.TrimSpace(element)
+		parameters[i] = element
 		switch strings.ToUpper(element) {
 		case StatusPlaceholder:
 			element = strconv.Itoa(result.HTTPStatus)
@@ -166,42 +208,68 @@ func sanitizeAndResolve(list []string, result *Result) []string {
 					wantLength = true
 					element = strings.TrimSuffix(strings.TrimPrefix(element, LengthFunctionPrefix), FunctionSuffix)
 				}
-				resolvedElement, resolvedElementLength, err := jsonpath.Eval(strings.Replace(element, fmt.Sprintf("%s.", BodyPlaceholder), "", 1), result.Body)
+				resolvedElement, resolvedElementLength, err := jsonpath.Eval(strings.TrimPrefix(element, BodyPlaceholder+"."), result.Body)
 				if err != nil {
 					if err.Error() != "unexpected end of JSON input" {
 						result.Errors = append(result.Errors, err.Error())
 					}
 					if wantLength {
-						element = fmt.Sprintf("len(%s) %s", element, InvalidConditionElementSuffix)
+						element = LengthFunctionPrefix + element + FunctionSuffix + " " + InvalidConditionElementSuffix
 					} else {
-						element = fmt.Sprintf("%s %s", element, InvalidConditionElementSuffix)
+						element = element + " " + InvalidConditionElementSuffix
 					}
 				} else {
 					if wantLength {
-						element = fmt.Sprintf("%d", resolvedElementLength)
+						element = strconv.Itoa(resolvedElementLength)
 					} else {
 						element = resolvedElement
 					}
 				}
 			}
 		}
-		sanitizedList = append(sanitizedList, element)
+		resolvedParameters[i] = element
 	}
-	return sanitizedList
+	return parameters, resolvedParameters
 }
 
-func sanitizeAndResolveNumerical(list []string, result *Result) []int64 {
-	var sanitizedNumbers []int64
-	sanitizedList := sanitizeAndResolve(list, result)
-	for _, element := range sanitizedList {
+func sanitizeAndResolveNumerical(list []string, result *Result) (parameters []string, resolvedNumericalParameters []int64) {
+	parameters, resolvedParameters := sanitizeAndResolve(list, result)
+	for _, element := range resolvedParameters {
 		if duration, err := time.ParseDuration(element); duration != 0 && err == nil {
-			sanitizedNumbers = append(sanitizedNumbers, duration.Milliseconds())
+			resolvedNumericalParameters = append(resolvedNumericalParameters, duration.Milliseconds())
 		} else if number, err := strconv.ParseInt(element, 10, 64); err != nil {
 			// Default to 0 if the string couldn't be converted to an integer
-			sanitizedNumbers = append(sanitizedNumbers, 0)
+			resolvedNumericalParameters = append(resolvedNumericalParameters, 0)
 		} else {
-			sanitizedNumbers = append(sanitizedNumbers, number)
+			resolvedNumericalParameters = append(resolvedNumericalParameters, number)
 		}
 	}
-	return sanitizedNumbers
+	return parameters, resolvedNumericalParameters
+}
+
+func prettifyNumericalParameters(parameters []string, resolvedParameters []int64, operator string) string {
+	return prettify(parameters, []string{strconv.Itoa(int(resolvedParameters[0])), strconv.Itoa(int(resolvedParameters[1]))}, operator)
+}
+
+// XXX: make this configurable? i.e. show-resolved-conditions-on-failure
+func prettify(parameters []string, resolvedParameters []string, operator string) string {
+	// Since, in the event of an invalid path, the resolvedParameters also contain the condition itself,
+	// we'll return the resolvedParameters as-is.
+	if strings.HasSuffix(resolvedParameters[0], InvalidConditionElementSuffix) || strings.HasSuffix(resolvedParameters[1], InvalidConditionElementSuffix) {
+		return resolvedParameters[0] + " " + operator + " " + resolvedParameters[1]
+	}
+	// First element is a placeholder
+	if parameters[0] != resolvedParameters[0] && parameters[1] == resolvedParameters[1] {
+		return parameters[0] + " (" + resolvedParameters[0] + ") " + operator + " " + parameters[1]
+	}
+	// Second element is a placeholder
+	if parameters[0] == resolvedParameters[0] && parameters[1] != resolvedParameters[1] {
+		return parameters[0] + " " + operator + " " + parameters[1] + " (" + resolvedParameters[1] + ")"
+	}
+	// Both elements are placeholders...?
+	if parameters[0] != resolvedParameters[0] && parameters[1] != resolvedParameters[1] {
+		return parameters[0] + " (" + resolvedParameters[0] + ") " + operator + " " + parameters[1] + " (" + resolvedParameters[1] + ")"
+	}
+	// Neither elements are placeholders
+	return parameters[0] + " " + operator + " " + parameters[1]
 }

core/condition_bench_test.go

@@ -0,0 +1,75 @@
+package core
+
+import "testing"
+
+func BenchmarkCondition_evaluateWithBodyStringAny(b *testing.B) {
+	condition := Condition("[BODY].name == any(john.doe, jane.doe)")
+	for n := 0; n < b.N; n++ {
+		result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
+		condition.evaluate(result)
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkCondition_evaluateWithBodyStringAnyFailure(b *testing.B) {
+	condition := Condition("[BODY].name == any(john.doe, jane.doe)")
+	for n := 0; n < b.N; n++ {
+		result := &Result{Body: []byte("{\"name\": \"bob.doe\"}")}
+		condition.evaluate(result)
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkCondition_evaluateWithBodyString(b *testing.B) {
+	condition := Condition("[BODY].name == john.doe")
+	for n := 0; n < b.N; n++ {
+		result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
+		condition.evaluate(result)
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkCondition_evaluateWithBodyStringFailure(b *testing.B) {
+	condition := Condition("[BODY].name == john.doe")
+	for n := 0; n < b.N; n++ {
+		result := &Result{Body: []byte("{\"name\": \"bob.doe\"}")}
+		condition.evaluate(result)
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkCondition_evaluateWithBodyStringLen(b *testing.B) {
+	condition := Condition("len([BODY].name) == 8")
+	for n := 0; n < b.N; n++ {
+		result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
+		condition.evaluate(result)
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkCondition_evaluateWithBodyStringLenFailure(b *testing.B) {
+	condition := Condition("len([BODY].name) == 8")
+	for n := 0; n < b.N; n++ {
+		result := &Result{Body: []byte("{\"name\": \"bob.doe\"}")}
+		condition.evaluate(result)
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkCondition_evaluateWithStatus(b *testing.B) {
+	condition := Condition("[STATUS] == 200")
+	for n := 0; n < b.N; n++ {
+		result := &Result{HTTPStatus: 200}
+		condition.evaluate(result)
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkCondition_evaluateWithStatusFailure(b *testing.B) {
+	condition := Condition("[STATUS] == 200")
+	for n := 0; n < b.N; n++ {
+		result := &Result{HTTPStatus: 400}
+		condition.evaluate(result)
+	}
+	b.ReportAllocs()
+}

core/condition_test.go

@@ -1,6 +1,7 @@
 package core
 
 import (
+	"fmt"
 	"strconv"
 	"testing"
 	"time"
@@ -22,6 +23,9 @@ func TestCondition_evaluateWithStatus(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	if result.ConditionResults[0].Condition != string(condition) {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, condition, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithStatusFailure(t *testing.T) {
@@ -31,6 +35,10 @@ func TestCondition_evaluateWithStatusFailure(t *testing.T) {
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[STATUS] (500) == 200"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithStatusUsingLessThan(t *testing.T) {
@@ -40,6 +48,10 @@ func TestCondition_evaluateWithStatusUsingLessThan(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[STATUS] < 300"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithStatusFailureUsingLessThan(t *testing.T) {
@@ -49,6 +61,10 @@ func TestCondition_evaluateWithStatusFailureUsingLessThan(t *testing.T) {
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[STATUS] (404) < 300"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithResponseTimeUsingLessThan(t *testing.T) {
@@ -58,6 +74,10 @@ func TestCondition_evaluateWithResponseTimeUsingLessThan(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[RESPONSE_TIME] < 500"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithResponseTimeUsingLessThanDuration(t *testing.T) {
@@ -67,6 +87,10 @@ func TestCondition_evaluateWithResponseTimeUsingLessThanDuration(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[RESPONSE_TIME] < 1s"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithResponseTimeUsingLessThanInvalid(t *testing.T) {
@@ -76,6 +100,10 @@ func TestCondition_evaluateWithResponseTimeUsingLessThanInvalid(t *testing.T) {
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have failed because the condition has an invalid numerical value that should've automatically resolved to 0", condition)
 	}
+	expectedConditionDisplayed := "[RESPONSE_TIME] (50) < potato (0)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithResponseTimeUsingGreaterThan(t *testing.T) {
@@ -87,6 +115,10 @@ func TestCondition_evaluateWithResponseTimeUsingGreaterThan(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[RESPONSE_TIME] > 500"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithResponseTimeUsingGreaterThanDuration(t *testing.T) {
@@ -96,6 +128,10 @@ func TestCondition_evaluateWithResponseTimeUsingGreaterThanDuration(t *testing.T
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[RESPONSE_TIME] > 1s"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithResponseTimeUsingGreaterThanOrEqualTo(t *testing.T) {
@@ -105,6 +141,10 @@ func TestCondition_evaluateWithResponseTimeUsingGreaterThanOrEqualTo(t *testing.
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[RESPONSE_TIME] >= 500"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithResponseTimeUsingLessThanOrEqualTo(t *testing.T) {
@@ -114,6 +154,10 @@ func TestCondition_evaluateWithResponseTimeUsingLessThanOrEqualTo(t *testing.T)
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[RESPONSE_TIME] <= 500"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBody(t *testing.T) {
@@ -123,6 +167,10 @@ func TestCondition_evaluateWithBody(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY] == test"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPath(t *testing.T) {
@@ -132,6 +180,10 @@ func TestCondition_evaluateWithBodyJSONPath(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY].status == UP"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPathComplex(t *testing.T) {
@@ -141,31 +193,35 @@ func TestCondition_evaluateWithBodyJSONPathComplex(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY].data.name == john"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithInvalidBodyJSONPathComplex(t *testing.T) {
-	expectedResolvedCondition := "[BODY].data.name (INVALID) == john"
 	condition := Condition("[BODY].data.name == john")
 	result := &Result{Body: []byte("{\"data\": {\"id\": 1}}")}
 	condition.evaluate(result)
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure, because the path was invalid", condition)
 	}
-	if result.ConditionResults[0].Condition != expectedResolvedCondition {
-		t.Errorf("Condition '%s' should have resolved to '%s', but resolved to '%s' instead", condition, expectedResolvedCondition, result.ConditionResults[0].Condition)
+	expectedConditionDisplayed := "[BODY].data.name (INVALID) == john"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
 	}
 }
 
 func TestCondition_evaluateWithInvalidBodyJSONPathComplexWithLengthFunction(t *testing.T) {
-	expectedResolvedCondition := "len([BODY].data.name) (INVALID) == john"
 	condition := Condition("len([BODY].data.name) == john")
 	result := &Result{Body: []byte("{\"data\": {\"id\": 1}}")}
 	condition.evaluate(result)
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure, because the path was invalid", condition)
 	}
-	if result.ConditionResults[0].Condition != expectedResolvedCondition {
-		t.Errorf("Condition '%s' should have resolved to '%s', but resolved to '%s' instead", condition, expectedResolvedCondition, result.ConditionResults[0].Condition)
+	expectedConditionDisplayed := "len([BODY].data.name) (INVALID) == john"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
 	}
 }
 
@@ -176,6 +232,10 @@ func TestCondition_evaluateWithBodyJSONPathDoublePlaceholders(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY].user.firstName != [BODY].user.lastName"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPathDoublePlaceholdersFailure(t *testing.T) {
@@ -185,6 +245,10 @@ func TestCondition_evaluateWithBodyJSONPathDoublePlaceholdersFailure(t *testing.
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[BODY].user.firstName (john) == [BODY].user.lastName (doe)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPathLongInt(t *testing.T) {
@@ -194,6 +258,10 @@ func TestCondition_evaluateWithBodyJSONPathLongInt(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY].data.id == 1"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPathComplexInt(t *testing.T) {
@@ -203,6 +271,10 @@ func TestCondition_evaluateWithBodyJSONPathComplexInt(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY].data[1].id == 2"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPathComplexIntUsingGreaterThan(t *testing.T) {
@@ -212,6 +284,10 @@ func TestCondition_evaluateWithBodyJSONPathComplexIntUsingGreaterThan(t *testing
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY].data.id > 0"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPathComplexIntFailureUsingGreaterThan(t *testing.T) {
@@ -221,6 +297,10 @@ func TestCondition_evaluateWithBodyJSONPathComplexIntFailureUsingGreaterThan(t *
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[BODY].data.id (1) > 5"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPathComplexIntUsingLessThan(t *testing.T) {
@@ -230,6 +310,10 @@ func TestCondition_evaluateWithBodyJSONPathComplexIntUsingLessThan(t *testing.T)
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY].data.id < 5"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyJSONPathComplexIntFailureUsingLessThan(t *testing.T) {
@@ -239,6 +323,10 @@ func TestCondition_evaluateWithBodyJSONPathComplexIntFailureUsingLessThan(t *tes
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[BODY].data.id (10) < 5"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodySliceLength(t *testing.T) {
@@ -248,6 +336,10 @@ func TestCondition_evaluateWithBodySliceLength(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "len([BODY].data) == 3"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyStringLength(t *testing.T) {
@@ -257,6 +349,36 @@ func TestCondition_evaluateWithBodyStringLength(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "len([BODY].name) == 8"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
+}
+
+func TestCondition_evaluateWithBodyPattern(t *testing.T) {
+	condition := Condition("[BODY] == pat(*john*)")
+	result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+	expectedConditionDisplayed := "[BODY] == pat(*john*)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
+}
+
+func TestCondition_evaluateWithReverseBodyPattern(t *testing.T) {
+	condition := Condition("pat(*john*) == [BODY]")
+	result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+	expectedConditionDisplayed := "pat(*john*) == [BODY]"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyStringPattern(t *testing.T) {
@@ -266,6 +388,24 @@ func TestCondition_evaluateWithBodyStringPattern(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[BODY].name == pat(*ohn*)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
+}
+
+func TestCondition_evaluateWithBodyHTMLPattern(t *testing.T) {
+	var html = `<!DOCTYPE html><html lang="en"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /></head><body><div id="user">john.doe</div></body></html>`
+	condition := Condition("[BODY] == pat(*<div id=\"user\">john.doe</div>*)")
+	result := &Result{Body: []byte(html)}
+	condition.evaluate(result)
+	if !result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a success", condition)
+	}
+	expectedConditionDisplayed := "[BODY] == pat(*<div id=\"user\">john.doe</div>*)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithBodyStringPatternFailure(t *testing.T) {
@@ -275,14 +415,9 @@ func TestCondition_evaluateWithBodyStringPatternFailure(t *testing.T) {
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
-}
-
-func TestCondition_evaluateWithBodyPatternFailure(t *testing.T) {
-	condition := Condition("[BODY] == pat(*john*)")
-	result := &Result{Body: []byte("{\"name\": \"john.doe\"}")}
-	condition.evaluate(result)
-	if !result.ConditionResults[0].Success {
-		t.Errorf("Condition '%s' should have been a success", condition)
+	expectedConditionDisplayed := "[BODY].name (john.doe) == pat(bob*)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
 	}
 }
 
@@ -293,6 +428,10 @@ func TestCondition_evaluateWithIPPattern(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[IP] == pat(10.*)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithIPPatternFailure(t *testing.T) {
@@ -302,6 +441,10 @@ func TestCondition_evaluateWithIPPatternFailure(t *testing.T) {
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[IP] (255.255.255.255) == pat(10.*)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithStatusPattern(t *testing.T) {
@@ -311,6 +454,10 @@ func TestCondition_evaluateWithStatusPattern(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[STATUS] == pat(4*)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithStatusPatternFailure(t *testing.T) {
@@ -320,6 +467,105 @@ func TestCondition_evaluateWithStatusPatternFailure(t *testing.T) {
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[STATUS] (404) != pat(4*)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
+}
+
+func TestCondition_evaluateWithBodyStringAny(t *testing.T) {
+	condition := Condition("[BODY].name == any(john.doe, jane.doe)")
+	expectedConditionDisplayed := "[BODY].name == any(john.doe, jane.doe)"
+	results := []*Result{
+		{Body: []byte("{\"name\": \"john.doe\"}")},
+		{Body: []byte("{\"name\": \"jane.doe\"}")},
+	}
+	for _, result := range results {
+		success := condition.evaluate(result)
+		if !success || !result.ConditionResults[0].Success {
+			t.Errorf("Condition '%s' should have been a success", condition)
+		}
+		if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+			t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+		}
+	}
+}
+
+func TestCondition_evaluateWithBodyStringAnyFailure(t *testing.T) {
+	condition := Condition("[BODY].name == any(john.doe, jane.doe)")
+	result := &Result{Body: []byte("{\"name\": \"bob.doe\"}")}
+	condition.evaluate(result)
+	if result.ConditionResults[0].Success {
+		t.Errorf("Condition '%s' should have been a failure", condition)
+	}
+	expectedConditionDisplayed := "[BODY].name (bob.doe) == any(john.doe, jane.doe)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
+}
+
+func TestCondition_evaluateWithStatusAny(t *testing.T) {
+	condition := Condition("[STATUS] == any(200, 429)")
+	statuses := []int{200, 429}
+	for _, status := range statuses {
+		result := &Result{HTTPStatus: status}
+		condition.evaluate(result)
+		if !result.ConditionResults[0].Success {
+			t.Errorf("Condition '%s' should have been a success", condition)
+		}
+		expectedConditionDisplayed := "[STATUS] == any(200, 429)"
+		if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+			t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+		}
+	}
+}
+
+func TestCondition_evaluateWithReverseStatusAny(t *testing.T) {
+	condition := Condition("any(200, 429) == [STATUS]")
+	statuses := []int{200, 429}
+	for _, status := range statuses {
+		result := &Result{HTTPStatus: status}
+		condition.evaluate(result)
+		if !result.ConditionResults[0].Success {
+			t.Errorf("Condition '%s' should have been a success", condition)
+		}
+		expectedConditionDisplayed := "any(200, 429) == [STATUS]"
+		if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+			t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+		}
+	}
+}
+
+func TestCondition_evaluateWithStatusAnyFailure(t *testing.T) {
+	condition := Condition("[STATUS] == any(200, 429)")
+	statuses := []int{201, 400, 404, 500}
+	for _, status := range statuses {
+		result := &Result{HTTPStatus: status}
+		condition.evaluate(result)
+		if result.ConditionResults[0].Success {
+			t.Errorf("Condition '%s' should have been a failure", condition)
+		}
+		expectedConditionDisplayed := fmt.Sprintf("[STATUS] (%d) == any(200, 429)", status)
+		if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+			t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+		}
+	}
+}
+
+func TestCondition_evaluateWithReverseStatusAnyFailure(t *testing.T) {
+	condition := Condition("any(200, 429) == [STATUS]")
+	statuses := []int{201, 400, 404, 500}
+	for _, status := range statuses {
+		result := &Result{HTTPStatus: status}
+		condition.evaluate(result)
+		if result.ConditionResults[0].Success {
+			t.Errorf("Condition '%s' should have been a failure", condition)
+		}
+		expectedConditionDisplayed := fmt.Sprintf("any(200, 429) == [STATUS] (%d)", status)
+		if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+			t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+		}
+	}
 }
 
 func TestCondition_evaluateWithConnected(t *testing.T) {
@@ -329,6 +575,10 @@ func TestCondition_evaluateWithConnected(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[CONNECTED] == true"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithConnectedFailure(t *testing.T) {
@@ -338,6 +588,10 @@ func TestCondition_evaluateWithConnectedFailure(t *testing.T) {
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[CONNECTED] (false) == true"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithUnsetCertificateExpiration(t *testing.T) {
@@ -347,6 +601,10 @@ func TestCondition_evaluateWithUnsetCertificateExpiration(t *testing.T) {
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[CERTIFICATE_EXPIRATION] == 0"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithCertificateExpirationGreaterThanNumerical(t *testing.T) {
@@ -357,6 +615,10 @@ func TestCondition_evaluateWithCertificateExpirationGreaterThanNumerical(t *test
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[CERTIFICATE_EXPIRATION] > 2419200000"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithCertificateExpirationGreaterThanNumericalFailure(t *testing.T) {
@@ -367,6 +629,10 @@ func TestCondition_evaluateWithCertificateExpirationGreaterThanNumericalFailure(
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[CERTIFICATE_EXPIRATION] (1209600000) > 2419200000"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithCertificateExpirationGreaterThanDuration(t *testing.T) {
@@ -376,6 +642,10 @@ func TestCondition_evaluateWithCertificateExpirationGreaterThanDuration(t *testi
 	if !result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a success", condition)
 	}
+	expectedConditionDisplayed := "[CERTIFICATE_EXPIRATION] > 12h"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }
 
 func TestCondition_evaluateWithCertificateExpirationGreaterThanDurationFailure(t *testing.T) {
@@ -385,4 +655,8 @@ func TestCondition_evaluateWithCertificateExpirationGreaterThanDurationFailure(t
 	if result.ConditionResults[0].Success {
 		t.Errorf("Condition '%s' should have been a failure", condition)
 	}
+	expectedConditionDisplayed := "[CERTIFICATE_EXPIRATION] (86400000) > 48h (172800000)"
+	if result.ConditionResults[0].Condition != expectedConditionDisplayed {
+		t.Errorf("Condition '%s' should have resolved to '%s', got '%s'", condition, expectedConditionDisplayed, result.ConditionResults[0].Condition)
+	}
 }

core/dns_test.go

@@ -2,6 +2,8 @@ package core
 
 import (
 	"testing"
+
+	"github.com/TwinProduction/gatus/pattern"
 )
 
 func TestIntegrationQuery(t *testing.T) {
@@ -61,7 +63,7 @@ func TestIntegrationQuery(t *testing.T) {
 			},
 			inputURL:        "8.8.8.8",
 			expectedDNSCode: "NOERROR",
-			expectedBody:    "b.iana-servers.net.",
+			expectedBody:    "*.iana-servers.net.",
 		},
 		{
 			name: "test DNS with fake type and retrieve error",
@@ -87,8 +89,15 @@ func TestIntegrationQuery(t *testing.T) {
 				t.Errorf("DNSRCodePlaceholder '%s' should have been %s", result.DNSRCode, test.expectedDNSCode)
 			}
 
-			if string(result.Body) != test.expectedBody {
-				t.Errorf("got %s, expected result %s,", string(result.Body), test.expectedBody)
+			if test.inputDNS.QueryType == "NS" {
+				// Because there are often multiple nameservers backing a single domain, we'll only look at the suffix
+				if !pattern.Match(test.expectedBody, string(result.Body)) {
+					t.Errorf("got %s, expected result %s,", string(result.Body), test.expectedBody)
+				}
+			} else {
+				if string(result.Body) != test.expectedBody {
+					t.Errorf("got %s, expected result %s,", string(result.Body), test.expectedBody)
+				}
 			}
 		})
 	}

core/event.go

@@ -0,0 +1,26 @@
+package core
+
+import "time"
+
+// Event is something that happens at a specific time
+type Event struct {
+	// Type is the kind of event
+	Type EventType `json:"type"`
+
+	// Timestamp is the moment at which the event happened
+	Timestamp time.Time `json:"timestamp"`
+}
+
+// EventType is, uh, the types of events?
+type EventType string
+
+var (
+	// EventStart is a type of event that represents when a service starts being monitored
+	EventStart EventType = "START"
+
+	// EventHealthy is a type of event that represents a service passing all of its conditions
+	EventHealthy EventType = "HEALTHY"
+
+	// EventUnhealthy is a type of event that represents a service failing one or more of its conditions
+	EventUnhealthy EventType = "UNHEALTHY"
+)

core/result.go

@@ -31,7 +31,7 @@ type Result struct {
 	Errors []string `json:"errors"`
 
 	// ConditionResults results of the service's conditions
-	ConditionResults []*ConditionResult `json:"condition-results"`
+	ConditionResults []*ConditionResult `json:"conditionResults"`
 
 	// Success whether the result signifies a success or not
 	Success bool `json:"success"`

core/service-status.go

@@ -1,5 +1,19 @@
 package core
 
+import (
+	"time"
+
+	"github.com/TwinProduction/gatus/util"
+)
+
+const (
+	// MaximumNumberOfResults is the maximum number of results that ServiceStatus.Results can have
+	MaximumNumberOfResults = 100
+
+	// MaximumNumberOfEvents is the maximum number of events that ServiceStatus.Events can have
+	MaximumNumberOfEvents = 50
+)
+
 // ServiceStatus contains the evaluation Results of a Service
 type ServiceStatus struct {
 	// Name of the service
@@ -8,8 +22,25 @@ type ServiceStatus struct {
 	// Group the service is a part of. Used for grouping multiple services together on the front end.
 	Group string `json:"group,omitempty"`
 
+	// Key is the key representing the ServiceStatus
+	Key string `json:"key"`
+
 	// Results is the list of service evaluation results
 	Results []*Result `json:"results"`
+
+	// Events is a list of events
+	//
+	// We don't expose this through JSON, because the main dashboard doesn't need to have this data.
+	// However, the detailed service page does leverage this by including it to a map that will be
+	// marshalled alongside the ServiceStatus.
+	Events []*Event `json:"-"`
+
+	// Uptime information on the service's uptime
+	//
+	// We don't expose this through JSON, because the main dashboard doesn't need to have this data.
+	// However, the detailed service page does leverage this by including it to a map that will be
+	// marshalled alongside the ServiceStatus.
+	Uptime *Uptime `json:"-"`
 }
 
 // NewServiceStatus creates a new ServiceStatus
@@ -17,15 +48,79 @@ func NewServiceStatus(service *Service) *ServiceStatus {
 	return &ServiceStatus{
 		Name:    service.Name,
 		Group:   service.Group,
+		Key:     util.ConvertGroupAndServiceToKey(service.Group, service.Name),
 		Results: make([]*Result, 0),
+		Events: []*Event{{
+			Type:      EventStart,
+			Timestamp: time.Now(),
+		}},
+		Uptime: NewUptime(),
 	}
 }
 
+// ShallowCopy creates a shallow copy of ServiceStatus
+func (ss *ServiceStatus) ShallowCopy() *ServiceStatus {
+	return &ServiceStatus{
+		Name:    ss.Name,
+		Group:   ss.Group,
+		Key:     ss.Key,
+		Results: ss.Results,
+		Events:  ss.Events,
+		Uptime:  ss.Uptime,
+	}
+}
+
+// WithResultPagination makes a shallow copy of the ServiceStatus with only the results
+// within the range defined by the page and pageSize parameters
+func (ss *ServiceStatus) WithResultPagination(page, pageSize int) *ServiceStatus {
+	shallowCopy := ss.ShallowCopy()
+	numberOfResults := len(shallowCopy.Results)
+	start := numberOfResults - (page * pageSize)
+	end := numberOfResults - ((page - 1) * pageSize)
+	if start > numberOfResults {
+		start = -1
+	} else if start < 0 {
+		start = 0
+	}
+	if end > numberOfResults {
+		end = numberOfResults
+	}
+	if start < 0 || end < 0 {
+		shallowCopy.Results = []*Result{}
+	} else {
+		shallowCopy.Results = shallowCopy.Results[start:end]
+	}
+	return shallowCopy
+}
+
 // AddResult adds a Result to ServiceStatus.Results and makes sure that there are
 // no more than 20 results in the Results slice
 func (ss *ServiceStatus) AddResult(result *Result) {
-	ss.Results = append(ss.Results, result)
-	if len(ss.Results) > 20 {
-		ss.Results = ss.Results[1:]
+	if len(ss.Results) > 0 {
+		// Check if there's any change since the last result
+		// OR there's only 1 event, which only happens when there's a start event
+		if ss.Results[len(ss.Results)-1].Success != result.Success || len(ss.Events) == 1 {
+			event := &Event{Timestamp: result.Timestamp}
+			if result.Success {
+				event.Type = EventHealthy
+			} else {
+				event.Type = EventUnhealthy
+			}
+			ss.Events = append(ss.Events, event)
+			if len(ss.Events) > MaximumNumberOfEvents {
+				// Doing ss.Events[1:] would usually be sufficient, but in the case where for some reason, the slice has
+				// more than one extra element, we can get rid of all of them at once and thus returning the slice to a
+				// length of MaximumNumberOfEvents by using ss.Events[len(ss.Events)-MaximumNumberOfEvents:] instead
+				ss.Events = ss.Events[len(ss.Events)-MaximumNumberOfEvents:]
+			}
+		}
 	}
+	ss.Results = append(ss.Results, result)
+	if len(ss.Results) > MaximumNumberOfResults {
+		// Doing ss.Results[1:] would usually be sufficient, but in the case where for some reason, the slice has more
+		// than one extra element, we can get rid of all of them at once and thus returning the slice to a length of
+		// MaximumNumberOfResults by using ss.Results[len(ss.Results)-MaximumNumberOfResults:] instead
+		ss.Results = ss.Results[len(ss.Results)-MaximumNumberOfResults:]
+	}
+	ss.Uptime.ProcessResult(result)
 }

core/service-status_test.go

@@ -1,6 +1,9 @@
 package core
 
-import "testing"
+import (
+	"testing"
+	"time"
+)
 
 func TestNewServiceStatus(t *testing.T) {
 	service := &Service{Name: "name", Group: "group"}
@@ -11,15 +14,53 @@ func TestNewServiceStatus(t *testing.T) {
 	if serviceStatus.Group != service.Group {
 		t.Errorf("expected %s, got %s", service.Group, serviceStatus.Group)
 	}
+	if serviceStatus.Key != "group_name" {
+		t.Errorf("expected %s, got %s", "group_name", serviceStatus.Key)
+	}
 }
 
 func TestServiceStatus_AddResult(t *testing.T) {
 	service := &Service{Name: "name", Group: "group"}
 	serviceStatus := NewServiceStatus(service)
-	for i := 0; i < 50; i++ {
-		serviceStatus.AddResult(&Result{})
+	for i := 0; i < MaximumNumberOfResults+10; i++ {
+		serviceStatus.AddResult(&Result{Timestamp: time.Now()})
 	}
-	if len(serviceStatus.Results) != 20 {
+	if len(serviceStatus.Results) != MaximumNumberOfResults {
 		t.Errorf("expected serviceStatus.Results to not exceed a length of 20")
 	}
 }
+
+func TestServiceStatus_WithResultPagination(t *testing.T) {
+	service := &Service{Name: "name", Group: "group"}
+	serviceStatus := NewServiceStatus(service)
+	for i := 0; i < 25; i++ {
+		serviceStatus.AddResult(&Result{Timestamp: time.Now()})
+	}
+	if len(serviceStatus.WithResultPagination(1, 1).Results) != 1 {
+		t.Errorf("expected to have 1 result")
+	}
+	if len(serviceStatus.WithResultPagination(5, 0).Results) != 0 {
+		t.Errorf("expected to have 0 results")
+	}
+	if len(serviceStatus.WithResultPagination(-1, 20).Results) != 0 {
+		t.Errorf("expected to have 0 result, because the page was invalid")
+	}
+	if len(serviceStatus.WithResultPagination(1, -1).Results) != 0 {
+		t.Errorf("expected to have 0 result, because the page size was invalid")
+	}
+	if len(serviceStatus.WithResultPagination(1, 10).Results) != 10 {
+		t.Errorf("expected to have 10 results, because given a page size of 10, page 1 should have 10 elements")
+	}
+	if len(serviceStatus.WithResultPagination(2, 10).Results) != 10 {
+		t.Errorf("expected to have 10 results, because given a page size of 10, page 2 should have 10 elements")
+	}
+	if len(serviceStatus.WithResultPagination(3, 10).Results) != 5 {
+		t.Errorf("expected to have 5 results, because given a page size of 10, page 3 should have 5 elements")
+	}
+	if len(serviceStatus.WithResultPagination(4, 10).Results) != 0 {
+		t.Errorf("expected to have 0 results, because given a page size of 10, page 4 should have 0 elements")
+	}
+	if len(serviceStatus.WithResultPagination(1, 50).Results) != 25 {
+		t.Errorf("expected to have 25 results, because there's only 25 results")
+	}
+}

core/service.go

@@ -20,6 +20,12 @@ const (
 
 	// ContentTypeHeader is the name of the header used to specify the content type
 	ContentTypeHeader = "Content-Type"
+
+	// UserAgentHeader is the name of the header used to specify the request's user agent
+	UserAgentHeader = "User-Agent"
+
+	// GatusUserAgent is the default user agent that Gatus uses to send requests.
+	GatusUserAgent = "Gatus/1.0"
 )
 
 var (
@@ -90,6 +96,10 @@ func (service *Service) ValidateAndSetDefaults() {
 	if len(service.Headers) == 0 {
 		service.Headers = make(map[string]string)
 	}
+	// Automatically add user agent header if there isn't one specified in the service configuration
+	if _, userAgentHeaderExists := service.Headers[UserAgentHeader]; !userAgentHeaderExists {
+		service.Headers[UserAgentHeader] = GatusUserAgent
+	}
 	// Automatically add "Content-Type: application/json" header if there's no Content-Type set
 	// and service.GraphQL is set to true
 	if _, contentTypeHeaderExists := service.Headers[ContentTypeHeader]; !contentTypeHeaderExists && service.GraphQL {
@@ -112,12 +122,10 @@ func (service *Service) ValidateAndSetDefaults() {
 	if len(service.Conditions) == 0 {
 		panic(ErrServiceWithNoCondition)
 	}
-
 	if service.DNS != nil {
 		service.DNS.validateAndSetDefault()
 		return
 	}
-
 	// Make sure that the request can be created
 	_, err := http.NewRequest(service.Method, service.URL, bytes.NewBuffer([]byte(service.Body)))
 	if err != nil {
@@ -205,9 +213,10 @@ func (service *Service) call(result *Result) {
 			result.Errors = append(result.Errors, err.Error())
 			return
 		}
+		defer response.Body.Close()
 		if response.TLS != nil && len(response.TLS.PeerCertificates) > 0 {
 			certificate := response.TLS.PeerCertificates[0]
-			result.CertificateExpiration = certificate.NotAfter.Sub(time.Now())
+			result.CertificateExpiration = time.Until(certificate.NotAfter)
 		}
 		result.HTTPStatus = response.StatusCode
 		result.Connected = response.StatusCode > 0

core/service_test.go

@@ -130,6 +130,32 @@ func TestService_buildHTTPRequest(t *testing.T) {
 	if request.Host != "twinnation.org" {
 		t.Error("request.Host should've been twinnation.org, but was", request.Host)
 	}
+	if userAgent := request.Header.Get("User-Agent"); userAgent != GatusUserAgent {
+		t.Errorf("request.Header.Get(User-Agent) should've been %s, but was %s", GatusUserAgent, userAgent)
+	}
+}
+
+func TestService_buildHTTPRequestWithCustomUserAgent(t *testing.T) {
+	condition := Condition("[STATUS] == 200")
+	service := Service{
+		Name:       "TwiNNatioN",
+		URL:        "https://twinnation.org/health",
+		Conditions: []*Condition{&condition},
+		Headers: map[string]string{
+			"User-Agent": "Test/2.0",
+		},
+	}
+	service.ValidateAndSetDefaults()
+	request := service.buildHTTPRequest()
+	if request.Method != "GET" {
+		t.Error("request.Method should've been GET, but was", request.Method)
+	}
+	if request.Host != "twinnation.org" {
+		t.Error("request.Host should've been twinnation.org, but was", request.Host)
+	}
+	if userAgent := request.Header.Get("User-Agent"); userAgent != "Test/2.0" {
+		t.Errorf("request.Header.Get(User-Agent) should've been %s, but was %s", "Test/2.0", userAgent)
+	}
 }
 
 func TestService_buildHTTPRequestWithHostHeader(t *testing.T) {
@@ -249,7 +275,7 @@ func TestIntegrationEvaluateHealthForDNS(t *testing.T) {
 func TestIntegrationEvaluateHealthForICMP(t *testing.T) {
 	conditionSuccess := Condition("[CONNECTED] == true")
 	service := Service{
-		Name:       "ICMP example",
+		Name:       "ICMP test",
 		URL:        "icmp://127.0.0.1",
 		Conditions: []*Condition{&conditionSuccess},
 	}
@@ -264,3 +290,17 @@ func TestIntegrationEvaluateHealthForICMP(t *testing.T) {
 		t.Error("Because all conditions passed, this should have been a success")
 	}
 }
+
+func TestService_getIP(t *testing.T) {
+	conditionSuccess := Condition("[CONNECTED] == true")
+	service := Service{
+		Name:       "Invalid URL test",
+		URL:        "",
+		Conditions: []*Condition{&conditionSuccess},
+	}
+	result := &Result{}
+	service.getIP(result)
+	if len(result.Errors) == 0 {
+		t.Error("service.getIP(result) should've thrown an error because the URL is invalid, thus cannot be parsed")
+	}
+}

core/uptime.go

@@ -0,0 +1,119 @@
+package core
+
+import (
+	"log"
+	"time"
+)
+
+const (
+	// RFC3339WithoutMinutesAndSeconds is the format defined by RFC3339 (see time.RFC3339) but with the minutes
+	// and seconds hardcoded to 0.
+	RFC3339WithoutMinutesAndSeconds = "2006-01-02T15:00:00Z07:00"
+
+	numberOfHoursInTenDays = 10 * 24
+	sevenDays              = 7 * 24 * time.Hour
+)
+
+// Uptime is the struct that contains the relevant data for calculating the uptime as well as the uptime itself
+type Uptime struct {
+	// LastSevenDays is the uptime percentage over the past 7 days
+	LastSevenDays float64 `json:"7d"`
+
+	// LastTwentyFourHours is the uptime percentage over the past 24 hours
+	LastTwentyFourHours float64 `json:"24h"`
+
+	// LastHour is the uptime percentage over the past hour
+	LastHour float64 `json:"1h"`
+
+	// SuccessCountPerHour is a map containing the number of successes per hour, per timestamp following the
+	// custom RFC3339WithoutMinutesAndSeconds format
+	SuccessCountPerHour map[string]uint64 `json:"-"`
+
+	// TotalCountPerHour is a map containing the total number of checks per hour, per timestamp following the
+	// custom RFC3339WithoutMinutesAndSeconds format
+	TotalCountPerHour map[string]uint64 `json:"-"`
+}
+
+// NewUptime creates a new Uptime
+func NewUptime() *Uptime {
+	return &Uptime{
+		SuccessCountPerHour: make(map[string]uint64),
+		TotalCountPerHour:   make(map[string]uint64),
+	}
+}
+
+// ProcessResult processes the result by extracting the relevant from the result and recalculating the uptime
+// if necessary
+func (uptime *Uptime) ProcessResult(result *Result) {
+	timestampDateWithHour := result.Timestamp.Format(RFC3339WithoutMinutesAndSeconds)
+	if result.Success {
+		uptime.SuccessCountPerHour[timestampDateWithHour]++
+	}
+	uptime.TotalCountPerHour[timestampDateWithHour]++
+	// Clean up only when we're starting to have too many useless keys
+	// Note that this is only triggered when there are more entries than there should be after
+	// 10 days, despite the fact that we are deleting everything that's older than 7 days.
+	// This is to prevent re-iterating on every `ProcessResult` as soon as the uptime has been logged for 7 days.
+	if len(uptime.TotalCountPerHour) > numberOfHoursInTenDays {
+		sevenDaysAgo := time.Now().Add(-(sevenDays + time.Hour))
+		for k := range uptime.TotalCountPerHour {
+			dateWithHour, err := time.Parse(time.RFC3339, k)
+			if err != nil {
+				// This shouldn't happen, but we'll log it in case it does happen
+				log.Println("[uptime][ProcessResult] Failed to parse programmatically generated timestamp:", err.Error())
+				continue
+			}
+			if sevenDaysAgo.Unix() > dateWithHour.Unix() {
+				delete(uptime.TotalCountPerHour, k)
+				delete(uptime.SuccessCountPerHour, k)
+			}
+		}
+	}
+	if result.Success {
+		// Recalculate uptime if at least one of the 1h, 24h or 7d uptime are not 100%
+		// If they're all 100%, then recalculating the uptime would be useless unless
+		// the result added was a failure (!result.Success)
+		if uptime.LastSevenDays != 1 || uptime.LastTwentyFourHours != 1 || uptime.LastHour != 1 {
+			uptime.recalculate()
+		}
+	} else {
+		// Recalculate uptime if at least one of the 1h, 24h or 7d uptime are not 0%
+		// If they're all 0%, then recalculating the uptime would be useless unless
+		// the result added was a success (result.Success)
+		if uptime.LastSevenDays != 0 || uptime.LastTwentyFourHours != 0 || uptime.LastHour != 0 {
+			uptime.recalculate()
+		}
+	}
+}
+
+func (uptime *Uptime) recalculate() {
+	uptimeBrackets := make(map[string]uint64)
+	now := time.Now()
+	// The oldest uptime bracket starts 7 days ago, so we'll start from there
+	timestamp := now.Add(-sevenDays)
+	for now.Sub(timestamp) >= 0 {
+		timestampDateWithHour := timestamp.Format(RFC3339WithoutMinutesAndSeconds)
+		successCountForTimestamp := uptime.SuccessCountPerHour[timestampDateWithHour]
+		totalCountForTimestamp := uptime.TotalCountPerHour[timestampDateWithHour]
+		uptimeBrackets["7d_success"] += successCountForTimestamp
+		uptimeBrackets["7d_total"] += totalCountForTimestamp
+		if now.Sub(timestamp) <= 24*time.Hour {
+			uptimeBrackets["24h_success"] += successCountForTimestamp
+			uptimeBrackets["24h_total"] += totalCountForTimestamp
+		}
+		if now.Sub(timestamp) <= time.Hour {
+			uptimeBrackets["1h_success"] += successCountForTimestamp
+			uptimeBrackets["1h_total"] += totalCountForTimestamp
+		}
+		timestamp = timestamp.Add(time.Hour)
+	}
+	if uptimeBrackets["7d_total"] > 0 {
+		uptime.LastSevenDays = float64(uptimeBrackets["7d_success"]) / float64(uptimeBrackets["7d_total"])
+	}
+	if uptimeBrackets["24h_total"] > 0 {
+		uptime.LastTwentyFourHours = float64(uptimeBrackets["24h_success"]) / float64(uptimeBrackets["24h_total"])
+	}
+	if uptimeBrackets["1h_total"] > 0 {
+		uptime.LastHour = float64(uptimeBrackets["1h_success"]) / float64(uptimeBrackets["1h_total"])
+	}
+}

core/uptime_test.go

@@ -0,0 +1,79 @@
+package core
+
+import (
+	"testing"
+	"time"
+)
+
+func TestUptime_ProcessResult(t *testing.T) {
+	service := &Service{Name: "name", Group: "group"}
+	serviceStatus := NewServiceStatus(service)
+	uptime := serviceStatus.Uptime
+
+	checkUptimes(t, serviceStatus, 0.00, 0.00, 0.00)
+
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-7 * 24 * time.Hour), Success: true})
+	checkUptimes(t, serviceStatus, 1.00, 0.00, 0.00)
+
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-6 * 24 * time.Hour), Success: false})
+	checkUptimes(t, serviceStatus, 0.50, 0.00, 0.00)
+
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-8 * 24 * time.Hour), Success: true})
+	checkUptimes(t, serviceStatus, 0.50, 0.00, 0.00)
+
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-24 * time.Hour), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-12 * time.Hour), Success: true})
+	checkUptimes(t, serviceStatus, 0.75, 1.00, 0.00)
+
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-1 * time.Hour), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-30 * time.Minute), Success: false})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-15 * time.Minute), Success: false})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-10 * time.Minute), Success: false})
+	checkUptimes(t, serviceStatus, 0.50, 0.50, 0.25)
+
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-120 * time.Hour), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-119 * time.Hour), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-118 * time.Hour), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-117 * time.Hour), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-10 * time.Hour), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-8 * time.Hour), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-30 * time.Minute), Success: true})
+	uptime.ProcessResult(&Result{Timestamp: time.Now().Add(-25 * time.Minute), Success: true})
+	checkUptimes(t, serviceStatus, 0.75, 0.70, 0.50)
+}
+
+func TestServiceStatus_AddResultUptimeIsCleaningUpAfterItself(t *testing.T) {
+	service := &Service{Name: "name", Group: "group"}
+	serviceStatus := NewServiceStatus(service)
+	now := time.Now()
+	now = time.Date(now.Year(), now.Month(), now.Day(), now.Hour(), 0, 0, 0, now.Location())
+	// Start 12 days ago
+	timestamp := now.Add(-12 * 24 * time.Hour)
+	for timestamp.Unix() <= now.Unix() {
+		serviceStatus.AddResult(&Result{Timestamp: timestamp, Success: true})
+		if len(serviceStatus.Uptime.SuccessCountPerHour) > numberOfHoursInTenDays {
+			t.Errorf("At no point in time should there be more than %d entries in serviceStatus.SuccessCountPerHour", numberOfHoursInTenDays)
+		}
+		//fmt.Printf("timestamp=%s; uptimeDuringLastHour=%f; timeAgo=%s\n", timestamp.Format(time.RFC3339), serviceStatus.UptimeDuringLastHour, time.Since(timestamp))
+		if now.Sub(timestamp) > time.Hour && serviceStatus.Uptime.LastHour != 0 {
+			t.Error("most recent timestamp > 1h ago, expected serviceStatus.Uptime.LastHour to be 0, got", serviceStatus.Uptime.LastHour)
+		}
+		if now.Sub(timestamp) < time.Hour && serviceStatus.Uptime.LastHour == 0 {
+			t.Error("most recent timestamp < 1h ago, expected serviceStatus.Uptime.LastHour to NOT be 0, got", serviceStatus.Uptime.LastHour)
+		}
+		// Simulate service with an interval of 1 minute
+		timestamp = timestamp.Add(3 * time.Minute)
+	}
+}
+
+func checkUptimes(t *testing.T, status *ServiceStatus, expectedUptimeDuringLastSevenDays, expectedUptimeDuringLastTwentyFourHours, expectedUptimeDuringLastHour float64) {
+	if status.Uptime.LastSevenDays != expectedUptimeDuringLastSevenDays {
+		t.Errorf("expected status.Uptime.LastSevenDays to be %f, got %f", expectedUptimeDuringLastHour, status.Uptime.LastSevenDays)
+	}
+	if status.Uptime.LastTwentyFourHours != expectedUptimeDuringLastTwentyFourHours {
+		t.Errorf("expected status.Uptime.LastTwentyFourHours to be %f, got %f", expectedUptimeDuringLastTwentyFourHours, status.Uptime.LastTwentyFourHours)
+	}
+	if status.Uptime.LastHour != expectedUptimeDuringLastHour {
+		t.Errorf("expected status.Uptime.LastHour to be %f, got %f", expectedUptimeDuringLastHour, status.Uptime.LastHour)
+	}
+}

example/docker-compose-mattermost/config.yaml

@@ -1,6 +1,16 @@
+alerting:
+  mattermost:
+    webhook-url: "http://mattermost:8065/hooks/tokengoeshere"
+    insecure: true
+
 services:
   - name: example
     url: http://example.org
-    interval: 30s
+    interval: 1m
+    alerts:
+      - type: mattermost
+        enabled: true
+        description: "healthcheck failed 3 times in a row"
+        send-on-resolved: true
     conditions:
       - "[STATUS] == 200"

example/docker-compose-mattermost/docker-compose.yml

@@ -1,13 +1,24 @@
 version: "3.8"
-services:
-    gatus:
-        image: twinproduction/gatus:latest
-        ports:
-          - 8080:8080
-        volumes:
-          - ./config.yaml:/config/config.yaml
 
-    mattermost-preview:
-        image: mattermost/mattermost-preview:latest
-        ports:
-          - 8065:8065
+services:
+  gatus:
+    container_name: gatus
+    image: twinproduction/gatus:latest
+    ports:
+      - 8080:8080
+    volumes:
+      - ./config.yaml:/config/config.yaml
+    networks:
+      - default
+
+  mattermost:
+    container_name: mattermost
+    image: mattermost/mattermost-preview:5.26.0
+    ports:
+      - 8065:8065
+    networks:
+      - default
+
+networks:
+  default:
+    driver: bridge

example/kubernetes-with-auto-discovery/gatus.yaml

@@ -81,11 +81,11 @@ spec:
               protocol: TCP
           resources:
             limits:
-              cpu: 200m
-              memory: 50M
+              cpu: 250m
+              memory: 100M
             requests:
               cpu: 50m
-              memory: 20M
+              memory: 30M
           volumeMounts:
             - mountPath: /config
               name: gatus-config

example/kubernetes/gatus.yaml

@@ -59,11 +59,11 @@ spec:
               protocol: TCP
           resources:
             limits:
-              cpu: 200m
-              memory: 50M
+              cpu: 250m
+              memory: 100M
             requests:
               cpu: 50m
-              memory: 20M
+              memory: 30M
           volumeMounts:
             - mountPath: /config
               name: gatus-config

go.mod

@@ -4,8 +4,11 @@ go 1.15
 
 require (
 	cloud.google.com/go v0.74.0 // indirect
+	github.com/TwinProduction/gocache v1.2.1
+	github.com/TwinProduction/health v1.0.0
 	github.com/go-ping/ping v0.0.0-20201115131931-3300c582a663
 	github.com/google/gofuzz v1.2.0 // indirect
+	github.com/gorilla/mux v1.8.0
 	github.com/imdario/mergo v0.3.11 // indirect
 	github.com/miekg/dns v1.1.35
 	github.com/prometheus/client_golang v1.9.0

go.sum

@@ -50,6 +50,10 @@ github.com/PuerkitoBio/purell v1.0.0/go.mod h1:c11w/QuzBsJSee3cPx9rAFu61PvFxuPbt
 github.com/PuerkitoBio/urlesc v0.0.0-20160726150825-5bd2802263f2/go.mod h1:uGdkoq3SwY9Y+13GIhn11/XLaGBb4BfwItxLd5jeuXE=
 github.com/Shopify/sarama v1.19.0/go.mod h1:FVkBWblsNy7DGZRfXLU0O9RCGt5g3g3yEuWXgklEdEo=
 github.com/Shopify/toxiproxy v2.1.4+incompatible/go.mod h1:OXgGpZ6Cli1/URJOF1DMxUHB2q5Ap20/P/eIdh4G0pI=
+github.com/TwinProduction/gocache v1.2.1 h1:NAdMwO9SQEZFmX69YWx6fzhwb6fHakkLri0451c+V1w=
+github.com/TwinProduction/gocache v1.2.1/go.mod h1:6zkBoLjrFLkIISwkZTgLy67qliCGSon1xpORM4Ri5HM=
+github.com/TwinProduction/health v1.0.0 h1:TVyYTAORQQZ8LaptX8jCHZRCGCAO6e+oJx19BUIzQYY=
+github.com/TwinProduction/health v1.0.0/go.mod h1:ys4mYKUeEfYrWmkm60xLtPjTuLIEDQNBZaTZvenLG1c=
 github.com/VividCortex/gohistogram v1.0.0/go.mod h1:Pf5mBqqDxYaXu3hDrrU+w6nw50o/4+TcAqDqk/vUH7g=
 github.com/afex/hystrix-go v0.0.0-20180502004556-fa1af6a1f4f5/go.mod h1:SkGFH1ia65gfNATL8TAiHDNxPzPdmEL5uirI2Uyuz6c=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
@@ -113,6 +117,7 @@ github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5Kwzbycv
 github.com/franela/goblin v0.0.0-20200105215937-c9ffbefa60db/go.mod h1:7dvUGVsVBjqR7JHJk0brhHOZYGmfBYOrK0ZhYMEtBr4=
 github.com/franela/goreq v0.0.0-20171204163338-bcd34c9993f8/go.mod h1:ZhphrRTfi2rbfLwlschooIH4+wKKDR4Pdxhh+TRoA20=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
+github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
 github.com/ghodss/yaml v0.0.0-20150909031657-73d445a93680/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/ghodss/yaml v1.0.0/go.mod h1:4dBDuWmgqj2HViK6kFavaiC9ZROes6MMH2rRYeMEF04=
 github.com/go-gl/glfw v0.0.0-20190409004039-e6da0acd62b1/go.mod h1:vR7hzQXu2zJy9AVAgeJqvqgH9Q5CA+iKCZ2gyEVpxRU=
@@ -131,6 +136,7 @@ github.com/go-openapi/spec v0.0.0-20160808142527-6aced65f8501/go.mod h1:J8+jY1nA
 github.com/go-openapi/swag v0.0.0-20160704191624-1d0bd113de87/go.mod h1:DXUve3Dpr1UfpPtxFw+EFuQ41HhCWZfha5jSVRG7C7I=
 github.com/go-ping/ping v0.0.0-20201115131931-3300c582a663 h1:jI2GiiRh+pPbey52EVmbU6kuLiXqwy4CXZ4gwUBj8Y0=
 github.com/go-ping/ping v0.0.0-20201115131931-3300c582a663/go.mod h1:35JbSyV/BYqHwwRA6Zr1uVDm1637YlNOU61wI797NPI=
+github.com/go-redis/redis v6.15.9+incompatible/go.mod h1:NAIEuMOZ/fxfXJIrKDQDz8wamY7mA7PouImQ2Jvg6kA=
 github.com/go-sql-driver/mysql v1.4.0/go.mod h1:zAC/RDZ24gD3HViQzih4MyKcchzm+sOG5ZlKdlhCg5w=
 github.com/go-stack/stack v1.8.0/go.mod h1:v0f6uXyyMGvRgIKkXu+yp6POWl0qKG85gN/melR3HDY=
 github.com/gogo/googleapis v1.1.0/go.mod h1:gf4bu3Q80BeJ6H1S1vYPm8/ELATdvryBaNFGgqEef3s=
@@ -214,7 +220,10 @@ github.com/gophercloud/gophercloud v0.1.0/go.mod h1:vxM41WHh5uqHVBMZHzuwNOHh8XEo
 github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
 github.com/gorilla/context v1.1.1/go.mod h1:kBGZzfjB9CEq2AlWe17Uuf7NDRt0dE0s8S51q0aT7Yg=
 github.com/gorilla/mux v1.6.2/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
+github.com/gorilla/mux v1.7.3 h1:gnP5JzjVOuiZD07fKKToCAOjS0yOpj/qPETTXCCS6hw=
 github.com/gorilla/mux v1.7.3/go.mod h1:1lud6UwP+6orDFRuTfBEV8e9/aOM/c4fVVCaMa2zaAs=
+github.com/gorilla/mux v1.8.0 h1:i40aqfkR1h2SlN9hojwV5ZA91wcXFOvkdNIeFDP5koI=
+github.com/gorilla/mux v1.8.0/go.mod h1:DVbg23sWSpFRCP0SfiEN6jmj59UnW/n46BH5rLB71So=
 github.com/gorilla/websocket v0.0.0-20170926233335-4201258b820c/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
 github.com/gregjones/httpcache v0.0.0-20180305231024-9cad4c3443a7/go.mod h1:FecbI9+v66THATjSRHfNgh1IVFe/9kFxbXtjV0ctIMA=
 github.com/grpc-ecosystem/go-grpc-middleware v1.0.1-0.20190118093823-f849b5445de4/go.mod h1:FiyG127CGDf3tlThmgyCl78X/SZQqEOJBCDaAfeWzPs=
@@ -310,6 +319,7 @@ github.com/nats-io/nats.go v1.9.1/go.mod h1:ZjDU1L/7fJ09jvUSRVBR2e7+RnLiiIQyqyzE
 github.com/nats-io/nkeys v0.1.0/go.mod h1:xpnFELMwJABBLVhffcfd1MZx6VsNRFpEugbxziKVo7w=
 github.com/nats-io/nkeys v0.1.3/go.mod h1:xpnFELMwJABBLVhffcfd1MZx6VsNRFpEugbxziKVo7w=
 github.com/nats-io/nuid v1.0.1/go.mod h1:19wcPz3Ph3q0Jbyiqsd0kePYG7A95tJPxeL+1OSON2c=
+github.com/nxadm/tail v1.4.4/go.mod h1:kenIhsEOeOJmVchQTgglprH7qJGnHDVpk1VPCcaMI8A=
 github.com/oklog/oklog v0.3.2/go.mod h1:FCV+B7mhrz4o+ueLpx+KqkyXRGMWOYEvfiXtdGtbWGs=
 github.com/oklog/run v1.0.0/go.mod h1:dlhp/R75TPv97u0XWUtDeV/lRKWPKSdTuV0TZvrmrQA=
 github.com/olekukonko/tablewriter v0.0.0-20170122224234-a0225b3f23b5/go.mod h1:vsDQFd/mU46D+Z4whnwzcISnGGzXWMclvtLoiIKAKIo=
@@ -317,9 +327,14 @@ github.com/onsi/ginkgo v0.0.0-20170829012221-11459a886d9c/go.mod h1:lLunBs/Ym6LB
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/ginkgo v1.7.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/ginkgo v1.11.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
+github.com/onsi/ginkgo v1.12.1/go.mod h1:zj2OWP4+oCPe1qIXoGWkgMRwljMUYCdkwsT2108oapk=
+github.com/onsi/ginkgo v1.14.1/go.mod h1:iSB4RoI2tjJc9BBv4NKIKWKya62Rps+oPG/Lv9klQyY=
 github.com/onsi/gomega v0.0.0-20170829124025-dcabb60a477c/go.mod h1:C1qb7wdrVGGVU+Z6iS04AVkA3Q65CEZX59MT0QO5uiA=
 github.com/onsi/gomega v1.4.3/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY=
 github.com/onsi/gomega v1.7.0/go.mod h1:ex+gbHU/CVuBBDIJjb2X0qEXbFg53c61hWP/1CpauHY=
+github.com/onsi/gomega v1.7.1/go.mod h1:XdKZgCCFLUoM/7CFJVPcG8C1xQ1AJ0vpAezJrB7JYyY=
+github.com/onsi/gomega v1.10.1/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1ybHNo=
+github.com/onsi/gomega v1.10.2/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1ybHNo=
 github.com/op/go-logging v0.0.0-20160315200505-970db520ece7/go.mod h1:HzydrMdWErDVzsI23lYNej1Htcns9BCg93Dk0bBINWk=
 github.com/opentracing-contrib/go-observer v0.0.0-20170622124052-a52f23424492/go.mod h1:Ngi6UdF0k5OKD5t5wlmGhe/EDKPoUM3BXZSSfIuJbis=
 github.com/opentracing/basictracer-go v1.0.0/go.mod h1:QfBfYuafItcjQuMwinw9GhYKwFXS9KnPs5lxoYwgW74=
@@ -407,6 +422,7 @@ github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJy
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
+github.com/tidwall/redcon v1.3.2/go.mod h1:bdYBm4rlcWpst2XMwKVzWDF9CoUxEbUmM7CQrKeOZas=
 github.com/tmc/grpc-websocket-proxy v0.0.0-20170815181823-89b8d40f7ca8/go.mod h1:ncp9v5uamzpCO7NfCPTXjqaC+bZgJeR0sMTm6dMHP7U=
 github.com/urfave/cli v1.20.0/go.mod h1:70zkFmudgCuE/ngEzBv17Jvp/497gISqfk5gWijbERA=
 github.com/urfave/cli v1.22.1/go.mod h1:Gos4lmkARVdJ6EkW0WaNv/tZAAMe9V7XWyB60NtXRu0=
@@ -416,6 +432,8 @@ github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9de
 github.com/yuin/goldmark v1.1.32/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.2.1/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 go.etcd.io/bbolt v1.3.3/go.mod h1:IbVyRI1SCnLcuJnV2u8VeU0CEYM7e686BmAb1XKL+uU=
+go.etcd.io/bbolt v1.3.5 h1:XAzx9gjCb0Rxj7EoqcClPD1d5ZBxZJk0jbuoPHenBt0=
+go.etcd.io/bbolt v1.3.5/go.mod h1:G5EMThwa9y8QZGBClrRx5EY+Yw9kAhnjy3bSjsnlVTQ=
 go.etcd.io/etcd v0.0.0-20191023171146-3cf2f69b5738/go.mod h1:dnLIgRNXwCJa5e+c6mIZCrds/GIG4ncV9HhK5PX7jPg=
 go.opencensus.io v0.20.1/go.mod h1:6WKK9ahsWS3RSO+PY9ZHZUfv2irvY6gN279GOPZjmmk=
 go.opencensus.io v0.20.2/go.mod h1:6WKK9ahsWS3RSO+PY9ZHZUfv2irvY6gN279GOPZjmmk=
@@ -511,6 +529,7 @@ golang.org/x/net v0.0.0-20200324143707-d3edc9973b7e/go.mod h1:qpuaurCH72eLCgpAm/
 golang.org/x/net v0.0.0-20200501053045-e0ff5e5a1de5/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/net v0.0.0-20200506145744-7e3656a0809f/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/net v0.0.0-20200513185701-a91f0712d120/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
+golang.org/x/net v0.0.0-20200520004742-59133d7f0dd7/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/net v0.0.0-20200520182314-0ba52f642ac2/go.mod h1:qpuaurCH72eLCgpAm/N6yyVIVM9cpaDIP3A8BGJEC5A=
 golang.org/x/net v0.0.0-20200625001655-4c5254603344 h1:vGXIOMxbNfDTk/aXCmfdLgkrSV+Z2tcbze+pEc3v5W4=
 golang.org/x/net v0.0.0-20200625001655-4c5254603344/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
@@ -563,10 +582,13 @@ golang.org/x/sys v0.0.0-20190606165138-5da285871e9c/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20190624142023-c5567b49c5d0/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190726091711-fc99dfbffb4e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190826190057-c7b8b68b1456/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20190904154756-749cb33beabd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20190924154521-2837fb4f24fe/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191001151750-bb3f8db39f24/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191005200804-aed5e4c7ecf9/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191022100944-742c48ecaeb7/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191120155948-bd437916bb0e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191204072324-ce4227a45e2e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191220142924-d4481acd189f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20191228213918-04cbcbbfeed8/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -582,6 +604,7 @@ golang.org/x/sys v0.0.0-20200331124033-c3d80250170d/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200501052902-10377860bb8e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200511232937-7e40ca221e25/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200515095857-1151b9dac4a9/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200519105757-fe76b779f299/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200523222454-059865788121/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200615200032-f1bc736245b1/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200625212154-ddb9806d33ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

k8s/client.go

@@ -16,13 +16,13 @@ import (
 	"k8s.io/client-go/tools/clientcmd"
 )
 
-// KubernetesClientApi is a minimal interface for interacting with Kubernetes
+// KubernetesClientAPI is a minimal interface for interacting with Kubernetes
 // Created mostly to make mocking the Kubernetes client easier
-type KubernetesClientApi interface {
+type KubernetesClientAPI interface {
 	GetServices(namespace string) ([]v1.Service, error)
 }
 
-// KubernetesClient is a working implementation of KubernetesClientApi
+// KubernetesClient is a working implementation of KubernetesClientAPI
 type KubernetesClient struct {
 	client *kubernetes.Clientset
 }
@@ -44,7 +44,7 @@ func NewKubernetesClient(client *kubernetes.Clientset) *KubernetesClient {
 }
 
 // NewClient creates a Kubernetes client for the given ClusterMode
-func NewClient(clusterMode ClusterMode) (KubernetesClientApi, error) {
+func NewClient(clusterMode ClusterMode) (KubernetesClientAPI, error) {
 	var kubeConfig *rest.Config
 	var err error
 	switch clusterMode {

k8s/k8s.go

@@ -5,6 +5,6 @@ import (
 )
 
 // GetKubernetesServices return a list of Services from the given namespace
-func GetKubernetesServices(client KubernetesClientApi, namespace string) ([]v1.Service, error) {
+func GetKubernetesServices(client KubernetesClientAPI, namespace string) ([]v1.Service, error) {
 	return client.GetServices(namespace)
 }

main.go

@@ -1,45 +1,37 @@
 package main
 
 import (
-	"bytes"
-	"compress/gzip"
 	"log"
-	"net/http"
 	"os"
-	"strings"
-	"time"
+	"os/signal"
+	"syscall"
 
 	"github.com/TwinProduction/gatus/config"
-	"github.com/TwinProduction/gatus/security"
+	"github.com/TwinProduction/gatus/controller"
+	"github.com/TwinProduction/gatus/storage"
 	"github.com/TwinProduction/gatus/watchdog"
-	"github.com/prometheus/client_golang/prometheus/promhttp"
-)
-
-const cacheTTL = 10 * time.Second
-
-var (
-	cachedServiceStatuses          []byte
-	cachedServiceStatusesGzipped   []byte
-	cachedServiceStatusesTimestamp time.Time
 )
 
 func main() {
 	cfg := loadConfiguration()
-	statusesHandler := serviceStatusesHandler
-	if cfg.Security != nil && cfg.Security.IsValid() {
-		statusesHandler = security.Handler(serviceStatusesHandler, cfg.Security)
-	}
-	http.HandleFunc("/favicon.ico", favIconHandler) // favicon needs to be always served from the root
-	http.HandleFunc(cfg.Web.PrependWithContextRoot("/api/v1/statuses"), statusesHandler)
-	http.HandleFunc(cfg.Web.PrependWithContextRoot("/health"), healthHandler)
-	http.Handle(cfg.Web.ContextRoot, GzipHandler(http.StripPrefix(cfg.Web.ContextRoot, http.FileServer(http.Dir("./static")))))
-
-	if cfg.Metrics {
-		http.Handle(cfg.Web.PrependWithContextRoot("/metrics"), promhttp.Handler())
-	}
-	log.Printf("[main][main] Listening on %s%s\n", cfg.Web.SocketAddress(), cfg.Web.ContextRoot)
 	go watchdog.Monitor(cfg)
-	log.Fatal(http.ListenAndServe(cfg.Web.SocketAddress(), nil))
+	go controller.Handle()
+	// Wait for termination signal
+	sig := make(chan os.Signal, 1)
+	done := make(chan bool, 1)
+	signal.Notify(sig, os.Interrupt, syscall.SIGTERM)
+	go func() {
+		<-sig
+		log.Println("Received termination signal, attempting to gracefully shut down")
+		controller.Shutdown()
+		err := storage.Get().Save()
+		if err != nil {
+			log.Println("Failed to save storage provider:", err.Error())
+		}
+		done <- true
+	}()
+	<-done
+	log.Println("Shutting down")
 }
 
 func loadConfiguration() *config.Config {
@@ -55,43 +47,3 @@ func loadConfiguration() *config.Config {
 	}
 	return config.Get()
 }
-
-func serviceStatusesHandler(writer http.ResponseWriter, r *http.Request) {
-	if isExpired := cachedServiceStatusesTimestamp.IsZero() || time.Now().Sub(cachedServiceStatusesTimestamp) > cacheTTL; isExpired {
-		buffer := &bytes.Buffer{}
-		gzipWriter := gzip.NewWriter(buffer)
-		data, err := watchdog.GetJSONEncodedServiceStatuses()
-		if err != nil {
-			log.Printf("[main][serviceStatusesHandler] Unable to marshal object to JSON: %s", err.Error())
-			writer.WriteHeader(http.StatusInternalServerError)
-			_, _ = writer.Write([]byte("Unable to marshal object to JSON"))
-			return
-		}
-		gzipWriter.Write(data)
-		gzipWriter.Close()
-		cachedServiceStatuses = data
-		cachedServiceStatusesGzipped = buffer.Bytes()
-		cachedServiceStatusesTimestamp = time.Now()
-	}
-	var data []byte
-	if strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
-		writer.Header().Set("Content-Encoding", "gzip")
-		data = cachedServiceStatusesGzipped
-	} else {
-		data = cachedServiceStatuses
-	}
-	writer.Header().Add("Content-type", "application/json")
-	writer.WriteHeader(http.StatusOK)
-	_, _ = writer.Write(data)
-}
-
-func healthHandler(writer http.ResponseWriter, _ *http.Request) {
-	writer.Header().Add("Content-type", "application/json")
-	writer.WriteHeader(http.StatusOK)
-	_, _ = writer.Write([]byte("{\"status\":\"UP\"}"))
-}
-
-// favIconHandler handles requests for /favicon.ico
-func favIconHandler(writer http.ResponseWriter, request *http.Request) {
-	http.ServeFile(writer, request, "./static/favicon.ico")
-}

pattern/pattern.go

@@ -1,12 +1,20 @@
 package pattern
 
-import "path/filepath"
+import (
+	"path/filepath"
+	"strings"
+)
 
 // Match checks whether a string matches a pattern
 func Match(pattern, s string) bool {
 	if pattern == "*" {
 		return true
 	}
+	// Separators found in the string break filepath.Match, so we'll remove all of them.
+	// This has a pretty significant impact on performance when there are separators in
+	// the strings, but at least it doesn't break filepath.Match.
+	s = strings.ReplaceAll(s, string(filepath.Separator), "")
+	pattern = strings.ReplaceAll(pattern, string(filepath.Separator), "")
 	matched, _ := filepath.Match(pattern, s)
 	return matched
 }

pattern/pattern_bench_test.go

@@ -0,0 +1,21 @@
+package pattern
+
+import "testing"
+
+func BenchmarkMatch(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		if !Match("*ing*", "livingroom") {
+			b.Error("should've matched")
+		}
+	}
+	b.ReportAllocs()
+}
+
+func BenchmarkMatchWithBackslash(b *testing.B) {
+	for n := 0; n < b.N; n++ {
+		if !Match("*ing*", "living\\room") {
+			b.Error("should've matched")
+		}
+	}
+	b.ReportAllocs()
+}

pattern/pattern_test.go

@@ -1,6 +1,9 @@
 package pattern
 
-import "testing"
+import (
+	"fmt"
+	"testing"
+)
 
 func TestMatch(t *testing.T) {
 	testMatch(t, "*", "livingroom_123", true)
@@ -15,6 +18,7 @@ func TestMatch(t *testing.T) {
 	testMatch(t, "*vin*om*2*", "livingroom_123", true)
 	testMatch(t, "livingroom_123", "livingroom_123", true)
 	testMatch(t, "*livingroom_123*", "livingroom_123", true)
+	testMatch(t, "*test*", "\\test", true)
 	testMatch(t, "livingroom", "livingroom_123", false)
 	testMatch(t, "livingroom123", "livingroom_123", false)
 	testMatch(t, "what", "livingroom_123", false)
@@ -24,14 +28,16 @@ func TestMatch(t *testing.T) {
 }
 
 func testMatch(t *testing.T, pattern, key string, expectedToMatch bool) {
-	matched := Match(pattern, key)
-	if expectedToMatch {
-		if !matched {
-			t.Errorf("%s should've matched pattern '%s'", key, pattern)
+	t.Run(fmt.Sprintf("pattern '%s' from '%s'", pattern, key), func(t *testing.T) {
+		matched := Match(pattern, key)
+		if expectedToMatch {
+			if !matched {
+				t.Errorf("%s should've matched pattern '%s'", key, pattern)
+			}
+		} else {
+			if matched {
+				t.Errorf("%s shouldn't have matched pattern '%s'", key, pattern)
+			}
 		}
-	} else {
-		if matched {
-			t.Errorf("%s shouldn't have matched pattern '%s'", key, pattern)
-		}
-	}
+	})
 }

static/index.html

@@ -1,392 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-<head>
-	<title>Health Dashboard</title>
-	<meta name="viewport" content="width=device-width, initial-scale=1" />
-	<link rel="stylesheet" href="./bootstrap.min.css" />
-	<style>
-		html, body {
-			background-color: #f7f9fb;
-		}
-		html {
-			height: 100%;
-		}
-		#results div.container:first-child {
-			border-top-left-radius: 3px;
-			border-top-right-radius: 3px;
-		}
-		#results div.container:last-child {
-			border-bottom-left-radius: 3px;
-			border-bottom-right-radius: 3px;
-			border-bottom-width: 1px;
-			border-color: #dee2e6;
-			border-style: solid;
-		}
-		.status {
-			cursor: pointer;
-			transition: all 500ms ease-in-out;
-			overflow-x: hidden;
-			padding: .25em 0;
-			color: white;
-		}
-		.title {
-			font-size: 2.5rem;
-		}
-		.status:hover {
-			opacity: 0.7;
-			transition: opacity 100ms ease-in-out;
-			color: black;
-		}
-		.status-over-time {
-			overflow: auto;
-		}
-		.status-over-time>span:not(:last-child) {
-			margin-left: 2px;
-		}
-		.status-time-ago {
-			color: #6a737d;
-			opacity: 0.5;
-			margin-top: 5px;
-		}
-		.status-min-max-ms {
-			overflow-x: hidden;
-		}
-		#tooltip {
-			position: fixed;
-			top: 0;
-			left: 0;
-			background-color: white;
-			border: 1px solid lightgray;
-			border-radius: 4px;
-			padding: 6px;
-			font-size: 13px;
-		}
-		#tooltip code {
-			color: #212529;
-			line-height: 1;
-		}
-		#tooltip .tooltip-title {
-			font-weight: bold;
-			margin-bottom: 0;
-			display: block;
-		}
-		#tooltip .tooltip-title {
-			margin-top: 8px;
-		}
-		#tooltip>.tooltip-title:first-child {
-			margin-top: 0;
-		}
-		#social {
-			position: fixed;
-			right: 5px;
-			bottom: 5px;
-			padding: 5px;
-			margin: 0;
-			z-index: 100;
-		}
-		#social img {
-			opacity: 0.3;
-		}
-		#social img:hover {
-			opacity: 1;
-		}
-		#settings {
-			position: fixed;
-			left: 5px;
-			bottom: 5px;
-			padding: 5px;
-		}
-		#settings select:focus {
-			box-shadow: none;
-		}
-		.service-group {
-            cursor: pointer;
-            user-select: none;
-		}
-        .service-group h5:hover {
-            color: #1b1e21 !important;
-        }
-	</style>
-</head>
-<body>
-	<div class="container my-3 rounded p-3 border shadow">
-		<div class="mb-2">
-			<div class="row">
-				<div class="col-8 text-left my-auto">
-					<div class="title display-4">Health Status</div>
-				</div>
-				<div class="col-4 text-right">
-					<img src="logo.png" alt="Gatus" style="position: relative; min-width: 50px; max-width: 200px; width: 20%;"/>
-				</div>
-			</div>
-		</div>
-		<div id="results"></div>
-	</div>
-
-	<div id="tooltip" style="display: none">
-		<div class="tooltip-title">Timestamp:</div>
-		<code id="tooltip-timestamp">...</code>
-		<div class="tooltip-title">Response time:</div>
-		<code id="tooltip-response-time">...</code>
-		<div class="tooltip-title">Conditions:</div>
-		<code id="tooltip-conditions">...</code>
-		<div id="tooltip-errors-container">
-			<div class="tooltip-title">Errors:</div>
-			<code id="tooltip-errors">...</code>
-		</div>
-	</div>
-
-	<script src="./jquery.min.js"></script>
-
-	<div id="social">
-		<a href="https://github.com/TwinProduction/gatus" target="_blank" title="Gatus on GitHub">
-			<img src="./github.png" alt="GitHub" width="32" height="auto" />
-		</a>
-	</div>
-
-	<div id="settings">
-		<div class="input-group input-group-sm">
-			<div class="input-group-prepend">
-				<div class="input-group-text">&#x21bb;</div>
-			</div>
-			<select class="form-control form-control-sm" id="refresh-rate">
-				<option value="10">10s</option>
-				<option value="30" selected>30s</option>
-				<option value="60">1m</option>
-				<option value="120">2m</option>
-				<option value="300">5m</option>
-				<option value="600">10m</option>
-			</select>
-		</div>
-	</div>
-
-	<script>
-		let serviceStatuses = {};
-		let timerHandler = 0;
-		let refreshIntervalHandler = 0;
-		let userClickedStatus = false;
-
-		function showTooltip(serviceName, index, element) {
-			userClickedStatus = false;
-			clearTimeout(timerHandler);
-			let serviceResult = serviceStatuses[serviceName].results[index];
-			$("#tooltip-timestamp").text(prettifyTimestamp(serviceResult.timestamp));
-			$("#tooltip-response-time").text(parseInt(serviceResult.duration/1000000) + "ms");
-			// Populate the condition section
-			let conditions = "";
-			for (let i in serviceResult['condition-results']) {
-				let conditionResult = serviceResult['condition-results'][i];
-				conditions += (conditionResult.success ? "&#10003;" : "X") + " ~ " + htmlEntities(conditionResult.condition) + "<br />";
-			}
-			$("#tooltip-conditions").html(conditions);
-			// Populate the error section only if there are errors
-			if (serviceResult.errors && serviceResult.errors.length > 0) {
-				let errors = "";
-				for (let i in serviceResult.errors) {
-					errors += "- " + htmlEntities(serviceResult.errors[i]) + "<br />";
-				}
-				$("#tooltip-errors").html(errors);
-				$("#tooltip-errors-container").show();
-			} else {
-				$("#tooltip-errors-container").hide();
-			}
-			// Position tooltip
-			$("#tooltip").css({top: "0px", left: "0px"}).show();
-			let targetTopPosition = element.getBoundingClientRect().y + 30;
-			let targetLeftPosition = element.getBoundingClientRect().x;
-			// Make adjustments if necessary
-			let tooltipBoundingClientRect = document.querySelector('#tooltip').getBoundingClientRect();
-			if (targetLeftPosition + window.scrollX + tooltipBoundingClientRect.width + 50 > document.body.getBoundingClientRect().width) {
-				targetLeftPosition = element.getBoundingClientRect().x - tooltipBoundingClientRect.width + element.getBoundingClientRect().width;
-				if (targetLeftPosition < 0) {
-					targetLeftPosition += -targetLeftPosition;
-				}
-			}
-			if (targetTopPosition + window.scrollY + tooltipBoundingClientRect.height + 50 > document.body.getBoundingClientRect().height && targetTopPosition >= 0) {
-				targetTopPosition = element.getBoundingClientRect().y - (tooltipBoundingClientRect.height + 10);
-				if (targetTopPosition < 0) {
-					targetTopPosition = element.getBoundingClientRect().y + 30;
-				}
-			}
-			$("#tooltip").css({top: targetTopPosition + "px", left: targetLeftPosition + "px"});
-		}
-
-		function fadeTooltip() {
-			if (!userClickedStatus) {
-				timerHandler = setTimeout(function () {
-					$("#tooltip").hide();
-				}, 500);
-			}
-		}
-
-		function createStatusBadge(serviceStatusIndex, index, success) {
-			if (success) {
-				return "<span class='status badge badge-success' style='width: 5%' onmouseenter='showTooltip(\""+serviceStatusIndex+"\", "+index+", this)' onmouseleave='fadeTooltip()' onclick='userClickedStatus = !userClickedStatus;'>&#10003;</span>";
-			}
-			return "<span class='status badge badge-danger' style='width: 5%' onmouseenter='showTooltip(\""+serviceStatusIndex+"\", "+index+", this)' onmouseleave='fadeTooltip()' onclick='userClickedStatus = !userClickedStatus;'>X</span>";
-		}
-
-		function refreshStatuses() {
-			$.getJSON("./api/v1/statuses", function (data) {
-				// Update the table only if there's a change
-				if (JSON.stringify(serviceStatuses) !== JSON.stringify(data)) {
-					serviceStatuses = data;
-					buildTable();
-				}
-			});
-		}
-
-		function buildTable() {
-			let outputByGroup = {};
-			for (let serviceStatusIndex in serviceStatuses) {
-				let serviceStatusOverTime = "";
-				let serviceStatus = serviceStatuses[serviceStatusIndex];
-				let hostname = serviceStatus.results[serviceStatus.results.length-1].hostname;
-				let minResponseTime = null;
-				let maxResponseTime = null;
-				let newestTimestamp = null;
-				let oldestTimestamp = null;
-				for (let resultIndex in serviceStatus.results) {
-					let serviceResult = serviceStatus.results[resultIndex];
-					serviceStatusOverTime = createStatusBadge(serviceStatusIndex, resultIndex, serviceResult.success) + serviceStatusOverTime;
-					const responseTime = parseInt(serviceResult.duration/1000000);
-					if (minResponseTime == null || minResponseTime > responseTime) {
-						minResponseTime = responseTime;
-					}
-					if (maxResponseTime == null || maxResponseTime < responseTime) {
-						maxResponseTime = responseTime;
-					}
-					const timestamp = new Date(serviceResult.timestamp);
-					if (newestTimestamp == null || newestTimestamp < timestamp) {
-						newestTimestamp = timestamp;
-					}
-					if (oldestTimestamp == null || oldestTimestamp > timestamp) {
-						oldestTimestamp = timestamp;
-					}
-				}
-				let output = ""
-					+ "<div class='container py-3 border-left border-right border-top border-black rounded-0'>"
-					+ "  <div class='row mb-2'>"
-					+ "    <div class='col-md-10'>"
-					+ "      <span class='font-weight-bold'>" + serviceStatus.name + "</span> <span class='text-secondary font-weight-lighter'>- " + hostname + "</span>"
-					+ "    </div>"
-					+ "    <div class='col-md-2 text-right'>"
-					+ "      <span class='font-weight-lighter status-min-max-ms'>" + (minResponseTime === maxResponseTime ? minResponseTime : (minResponseTime + "-" + maxResponseTime)) + "ms</span>"
-					+ "    </div>"
-					+ "  </div>"
-					+ "  <div class='row'>"
-					+ "    <div class='col-12 d-flex flex-row-reverse status-over-time'>"
-					+ "      " + serviceStatusOverTime
-					+ "    </div>"
-					+ "  </div>"
-					+ "  <div class='row status-time-ago'>"
-					+ "    <div class='col-6'>"
-					+ "      " + generatePrettyTimeAgo(oldestTimestamp)
-					+ "    </div>"
-					+ "    <div class='col-6 text-right'>"
-					+ "      " + generatePrettyTimeAgo(newestTimestamp)
-					+ "    </div>"
-					+ "  </div>"
-					+ "</div>";
-				// create an empty entry if this group is new
-				if (!outputByGroup[serviceStatus.group]) {
-					outputByGroup[serviceStatus.group] = "";
-				}
-				outputByGroup[serviceStatus.group] += output;
-			}
-			let output = "";
-			for (let group in outputByGroup) {
-				// Services that don't have a group should be skipped and left for last
-				if (group === 'undefined') {
-					continue
-				}
-				let key = group.replace(/[^a-zA-Z0-9]/g, '');
-				let existingGroupContentSelector = $("#service-group-" + key + "-content");
-				let isCurrentlyHidden = existingGroupContentSelector.length && existingGroupContentSelector[0].style.display === 'none';
-				let groupStatus = "<span class='text-success'>&#10003;</span>";
-				if (outputByGroup[group].includes("badge badge-danger")) {
-					groupStatus = "<span class='text-warning'>~</span>";
-				}
-				output += ""
-					+ "<div class='mt-" + (output.length ? '4' : '3') + "'>"
-					+ "  <div class='container pt-2 border-left border-right border-top border-black border-bottom service-group' id='service-group-" + key + "' data-group='" + key + "' onclick='toggleGroup(this)'>"
-					+ "    <h5 class='text-secondary text-monospace pb-0'>"
-					+ "      " + groupStatus + " " + group
-					+ "      <span class='float-right service-group-arrow' id='service-group-" + key + "-arrow'>" + (isCurrentlyHidden ? "&#9660;" : "&#9650;") + "</span>"
-					+ "    </h5>"
-					+ "  </div>"
-					+ "  <div class='service-group-content' id='service-group-" + key + "-content' style='" + (isCurrentlyHidden ? "display: none;" : "") + "'>"
-					+ "    " + outputByGroup[group]
-					+ "  </div>"
-					+ "</div>";
-			}
-			// Add all services that don't have a group at the end
-			if (outputByGroup['undefined']) {
-				output += ""
-					+ "<div class='mt-" + (output.length ? '4' : '3') + "'>"
-					+ "  " + outputByGroup['undefined']
-					+ "</div>"
-			}
-			$("#results").html(output);
-		}
-
-		function toggleGroup(element) {
-			let selector = $("#service-group-" + element.dataset.group + "-content");
-			selector.toggle("fast", function() {
-				if (selector.length && selector[0].style.display === 'none') {
-					$("#service-group-" + element.dataset.group + "-arrow").html("&#9660;");
-				} else {
-					$("#service-group-" + element.dataset.group + "-arrow").html("&#9650;");
-				}
-			});
-		}
-
-		function prettifyTimestamp(timestamp) {
-			let date = new Date(timestamp);
-			let YYYY = date.getFullYear();
-			let MM = ((date.getMonth()+1)<10?"0":"")+""+(date.getMonth()+1);
-			let DD = ((date.getDate())<10?"0":"")+""+(date.getDate());
-			let hh = ((date.getHours())<10?"0":"")+""+(date.getHours());
-			let mm = ((date.getMinutes())<10?"0":"")+""+(date.getMinutes());
-			let ss = ((date.getSeconds())<10?"0":"")+""+(date.getSeconds());
-			return YYYY + "-" + MM + "-" + DD + " " + hh + ":" + mm + ":" + ss;
-		}
-
-		function generatePrettyTimeAgo(t) {
-			let differenceInMs = new Date().getTime() - new Date(t).getTime();
-			if (differenceInMs > 3600000) {
-				let hours = (differenceInMs/3600000).toFixed(0);
-				return hours + " hour" + (hours !== "1" ? "s" : "") + " ago";
-			}
-			if (differenceInMs > 60000) {
-				let minutes = (differenceInMs/60000).toFixed(0);
-				return minutes + " minute" + (minutes !== "1" ? "s" : "") + " ago";
-			}
-			return (differenceInMs/1000).toFixed(0) + " seconds ago";
-		}
-
-		function htmlEntities(s) {
-			return String(s)
-				.replace(/&/g, '&amp;')
-				.replace(/</g, '&lt;')
-				.replace(/>/g, '&gt;')
-				.replace(/"/g, '&quot;')
-				.replace(/'/g, '&apos;');
-		}
-
-		function setRefreshInterval(seconds) {
-			refreshStatuses();
-			refreshIntervalHandler = setInterval(function() {
-				refreshStatuses();
-			}, seconds * 1000);
-		}
-
-		$("#refresh-rate").change(function() {
-			clearInterval(refreshIntervalHandler);
-			setRefreshInterval($(this).val());
-		});
-		setRefreshInterval(30);
-		$("#refresh-rate").val(30);
-	</script>
-</body>
-</html>

storage/config.go

@@ -0,0 +1,8 @@
+package storage
+
+// Config is the configuration for alerting providers
+type Config struct {
+	// File is the path of the file to use for persistence
+	// If blank, persistence is disabled.
+	File string `yaml:"file"`
+}

storage/storage.go

@@ -0,0 +1,63 @@
+package storage
+
+import (
+	"log"
+	"time"
+
+	"github.com/TwinProduction/gatus/storage/store"
+	"github.com/TwinProduction/gatus/storage/store/memory"
+)
+
+var (
+	provider store.Store
+
+	// initialized keeps track of whether the storage provider was initialized
+	// Because store.Store is an interface, a nil check wouldn't be sufficient, so instead of doing reflection
+	// every single time Get is called, we'll just lazily keep track of its existence through this variable
+	initialized bool
+)
+
+// Get retrieves the storage provider
+func Get() store.Store {
+	if !initialized {
+		log.Println("[storage][Get] Provider requested before it was initialized, automatically initializing")
+		err := Initialize(nil)
+		if err != nil {
+			panic("failed to automatically initialize store: " + err.Error())
+		}
+	}
+	return provider
+}
+
+// Initialize instantiates the storage provider based on the Config provider
+func Initialize(cfg *Config) error {
+	initialized = true
+	var err error
+	if cfg == nil || len(cfg.File) == 0 {
+		log.Println("[storage][Initialize] Creating storage provider")
+		provider, err = memory.NewStore("")
+		if err != nil {
+			return err
+		}
+	} else {
+		log.Printf("[storage][Initialize] Creating storage provider with file=%s", cfg.File)
+		provider, err = memory.NewStore(cfg.File)
+		if err != nil {
+			return err
+		}
+		go autoSave(7 * time.Minute)
+	}
+	return nil
+}
+
+// autoSave automatically calls the Save function of the provider at every interval
+func autoSave(interval time.Duration) {
+	for {
+		time.Sleep(interval)
+		log.Printf("[storage][autoSave] Saving")
+		err := provider.Save()
+		if err != nil {
+			log.Println("[storage][autoSave] Save failed:", err.Error())
+		}
+	}
+}

storage/store/memory/memory.go

@@ -0,0 +1,104 @@
+package memory
+
+import (
+	"encoding/gob"
+
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/util"
+	"github.com/TwinProduction/gocache"
+)
+
+func init() {
+	gob.Register(&core.ServiceStatus{})
+	gob.Register(&core.Uptime{})
+	gob.Register(&core.Result{})
+	gob.Register(&core.Event{})
+}
+
+// Store that leverages gocache
+type Store struct {
+	file  string
+	cache *gocache.Cache
+}
+
+// NewStore creates a new store
+func NewStore(file string) (*Store, error) {
+	store := &Store{
+		file:  file,
+		cache: gocache.NewCache().WithMaxSize(gocache.NoMaxSize),
+	}
+	if len(file) > 0 {
+		_, err := store.cache.ReadFromFile(file)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return store, nil
+}
+
+// GetAllServiceStatusesWithResultPagination returns all monitored core.ServiceStatus
+// with a subset of core.Result defined by the page and pageSize parameters
+func (s *Store) GetAllServiceStatusesWithResultPagination(page, pageSize int) map[string]*core.ServiceStatus {
+	serviceStatuses := s.cache.GetAll()
+	pagedServiceStatuses := make(map[string]*core.ServiceStatus, len(serviceStatuses))
+	for k, v := range serviceStatuses {
+		pagedServiceStatuses[k] = v.(*core.ServiceStatus).WithResultPagination(page, pageSize)
+	}
+	return pagedServiceStatuses
+}
+
+// GetServiceStatus returns the service status for a given service name in the given group
+func (s *Store) GetServiceStatus(groupName, serviceName string) *core.ServiceStatus {
+	return s.GetServiceStatusByKey(util.ConvertGroupAndServiceToKey(groupName, serviceName))
+}
+
+// GetServiceStatusByKey returns the service status for a given key
+func (s *Store) GetServiceStatusByKey(key string) *core.ServiceStatus {
+	serviceStatus := s.cache.GetValue(key)
+	if serviceStatus == nil {
+		return nil
+	}
+	return serviceStatus.(*core.ServiceStatus).ShallowCopy()
+}
+
+// Insert adds the observed result for the specified service into the store
+func (s *Store) Insert(service *core.Service, result *core.Result) {
+	key := util.ConvertGroupAndServiceToKey(service.Group, service.Name)
+	serviceStatus, exists := s.cache.Get(key)
+	if !exists {
+		serviceStatus = core.NewServiceStatus(service)
+	}
+	serviceStatus.(*core.ServiceStatus).AddResult(result)
+	s.cache.Set(key, serviceStatus)
+}
+
+// DeleteAllServiceStatusesNotInKeys removes all ServiceStatus that are not within the keys provided
+func (s *Store) DeleteAllServiceStatusesNotInKeys(keys []string) int {
+	var keysToDelete []string
+	for _, existingKey := range s.cache.GetKeysByPattern("*", 0) {
+		shouldDelete := true
+		for _, key := range keys {
+			if existingKey == key {
+				shouldDelete = false
+				break
+			}
+		}
+		if shouldDelete {
+			keysToDelete = append(keysToDelete, existingKey)
+		}
+	}
+	return s.cache.DeleteAll(keysToDelete)
+}
+
+// Clear deletes everything from the store
+func (s *Store) Clear() {
+	s.cache.Clear()
+}
+
+// Save persists the cache to the store file
+func (s *Store) Save() error {
+	if len(s.file) > 0 {
+		return s.cache.SaveToFile(s.file)
+	}
+	return nil
+}

storage/store/memory/memory_test.go

@@ -0,0 +1,277 @@
+package memory
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/util"
+)
+
+var (
+	firstCondition  = core.Condition("[STATUS] == 200")
+	secondCondition = core.Condition("[RESPONSE_TIME] < 500")
+	thirdCondition  = core.Condition("[CERTIFICATE_EXPIRATION] < 72h")
+
+	timestamp = time.Now()
+
+	testService = core.Service{
+		Name:                    "name",
+		Group:                   "group",
+		URL:                     "https://example.org/what/ever",
+		Method:                  "GET",
+		Body:                    "body",
+		Interval:                30 * time.Second,
+		Conditions:              []*core.Condition{&firstCondition, &secondCondition, &thirdCondition},
+		Alerts:                  nil,
+		Insecure:                false,
+		NumberOfFailuresInARow:  0,
+		NumberOfSuccessesInARow: 0,
+	}
+	testSuccessfulResult = core.Result{
+		Hostname:              "example.org",
+		IP:                    "127.0.0.1",
+		HTTPStatus:            200,
+		Body:                  []byte("body"),
+		Errors:                nil,
+		Connected:             true,
+		Success:               true,
+		Timestamp:             timestamp,
+		Duration:              150 * time.Millisecond,
+		CertificateExpiration: 10 * time.Hour,
+		ConditionResults: []*core.ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   true,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   true,
+			},
+		},
+	}
+	testUnsuccessfulResult = core.Result{
+		Hostname:              "example.org",
+		IP:                    "127.0.0.1",
+		HTTPStatus:            200,
+		Body:                  []byte("body"),
+		Errors:                []string{"error-1", "error-2"},
+		Connected:             true,
+		Success:               false,
+		Timestamp:             timestamp,
+		Duration:              750 * time.Millisecond,
+		CertificateExpiration: 10 * time.Hour,
+		ConditionResults: []*core.ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   false,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   false,
+			},
+		},
+	}
+)
+
+func TestStore_Insert(t *testing.T) {
+	store, _ := NewStore("")
+	store.Insert(&testService, &testSuccessfulResult)
+	store.Insert(&testService, &testUnsuccessfulResult)
+
+	if store.cache.Count() != 1 {
+		t.Fatalf("expected 1 ServiceStatus, got %d", store.cache.Count())
+	}
+	key := fmt.Sprintf("%s_%s", testService.Group, testService.Name)
+	serviceStatus := store.GetServiceStatusByKey(key)
+	if serviceStatus == nil {
+		t.Fatalf("Store should've had key '%s', but didn't", key)
+	}
+	if len(serviceStatus.Results) != 2 {
+		t.Fatalf("Service '%s' should've had 2 results, but actually returned %d", serviceStatus.Name, len(serviceStatus.Results))
+	}
+	for i, r := range serviceStatus.Results {
+		expectedResult := store.GetServiceStatus(testService.Group, testService.Name).Results[i]
+		if r.HTTPStatus != expectedResult.HTTPStatus {
+			t.Errorf("Result at index %d should've had a HTTPStatus of %d, but was actually %d", i, expectedResult.HTTPStatus, r.HTTPStatus)
+		}
+		if r.DNSRCode != expectedResult.DNSRCode {
+			t.Errorf("Result at index %d should've had a DNSRCode of %s, but was actually %s", i, expectedResult.DNSRCode, r.DNSRCode)
+		}
+		if len(r.Body) != len(expectedResult.Body) {
+			t.Errorf("Result at index %d should've had a body of length %d, but was actually %d", i, len(expectedResult.Body), len(r.Body))
+		}
+		if r.Hostname != expectedResult.Hostname {
+			t.Errorf("Result at index %d should've had a Hostname of %s, but was actually %s", i, expectedResult.Hostname, r.Hostname)
+		}
+		if r.IP != expectedResult.IP {
+			t.Errorf("Result at index %d should've had a IP of %s, but was actually %s", i, expectedResult.IP, r.IP)
+		}
+		if r.Connected != expectedResult.Connected {
+			t.Errorf("Result at index %d should've had a Connected value of %t, but was actually %t", i, expectedResult.Connected, r.Connected)
+		}
+		if r.Duration != expectedResult.Duration {
+			t.Errorf("Result at index %d should've had a Duration of %s, but was actually %s", i, expectedResult.Duration.String(), r.Duration.String())
+		}
+		if len(r.Errors) != len(expectedResult.Errors) {
+			t.Errorf("Result at index %d should've had %d errors, but actually had %d errors", i, len(expectedResult.Errors), len(r.Errors))
+		}
+		if len(r.ConditionResults) != len(expectedResult.ConditionResults) {
+			t.Errorf("Result at index %d should've had %d ConditionResults, but actually had %d ConditionResults", i, len(expectedResult.ConditionResults), len(r.ConditionResults))
+		}
+		if r.Success != expectedResult.Success {
+			t.Errorf("Result at index %d should've had a Success of %t, but was actually %t", i, expectedResult.Success, r.Success)
+		}
+		if r.Timestamp != expectedResult.Timestamp {
+			t.Errorf("Result at index %d should've had a Timestamp of %s, but was actually %s", i, expectedResult.Timestamp.String(), r.Timestamp.String())
+		}
+		if r.CertificateExpiration != expectedResult.CertificateExpiration {
+			t.Errorf("Result at index %d should've had a CertificateExpiration of %s, but was actually %s", i, expectedResult.CertificateExpiration.String(), r.CertificateExpiration.String())
+		}
+	}
+}
+
+func TestStore_GetServiceStatus(t *testing.T) {
+	store, _ := NewStore("")
+	store.Insert(&testService, &testSuccessfulResult)
+	store.Insert(&testService, &testUnsuccessfulResult)
+
+	serviceStatus := store.GetServiceStatus(testService.Group, testService.Name)
+	if serviceStatus == nil {
+		t.Fatalf("serviceStatus shouldn't have been nil")
+	}
+	if serviceStatus.Uptime == nil {
+		t.Fatalf("serviceStatus.Uptime shouldn't have been nil")
+	}
+	if serviceStatus.Uptime.LastHour != 0.5 {
+		t.Errorf("serviceStatus.Uptime.LastHour should've been 0.5")
+	}
+	if serviceStatus.Uptime.LastTwentyFourHours != 0.5 {
+		t.Errorf("serviceStatus.Uptime.LastTwentyFourHours should've been 0.5")
+	}
+	if serviceStatus.Uptime.LastSevenDays != 0.5 {
+		t.Errorf("serviceStatus.Uptime.LastSevenDays should've been 0.5")
+	}
+}
+
+func TestStore_GetServiceStatusForMissingStatusReturnsNil(t *testing.T) {
+	store, _ := NewStore("")
+	store.Insert(&testService, &testSuccessfulResult)
+
+	serviceStatus := store.GetServiceStatus("nonexistantgroup", "nonexistantname")
+	if serviceStatus != nil {
+		t.Errorf("Returned service status for group '%s' and name '%s' not nil after inserting the service into the store", testService.Group, testService.Name)
+	}
+	serviceStatus = store.GetServiceStatus(testService.Group, "nonexistantname")
+	if serviceStatus != nil {
+		t.Errorf("Returned service status for group '%s' and name '%s' not nil after inserting the service into the store", testService.Group, "nonexistantname")
+	}
+	serviceStatus = store.GetServiceStatus("nonexistantgroup", testService.Name)
+	if serviceStatus != nil {
+		t.Errorf("Returned service status for group '%s' and name '%s' not nil after inserting the service into the store", "nonexistantgroup", testService.Name)
+	}
+}
+
+func TestStore_GetServiceStatusByKey(t *testing.T) {
+	store, _ := NewStore("")
+	store.Insert(&testService, &testSuccessfulResult)
+	store.Insert(&testService, &testUnsuccessfulResult)
+
+	serviceStatus := store.GetServiceStatusByKey(util.ConvertGroupAndServiceToKey(testService.Group, testService.Name))
+	if serviceStatus == nil {
+		t.Fatalf("serviceStatus shouldn't have been nil")
+	}
+	if serviceStatus.Uptime == nil {
+		t.Fatalf("serviceStatus.Uptime shouldn't have been nil")
+	}
+	if serviceStatus.Uptime.LastHour != 0.5 {
+		t.Errorf("serviceStatus.Uptime.LastHour should've been 0.5")
+	}
+	if serviceStatus.Uptime.LastTwentyFourHours != 0.5 {
+		t.Errorf("serviceStatus.Uptime.LastTwentyFourHours should've been 0.5")
+	}
+	if serviceStatus.Uptime.LastSevenDays != 0.5 {
+		t.Errorf("serviceStatus.Uptime.LastSevenDays should've been 0.5")
+	}
+}
+
+func TestStore_GetAllServiceStatusesWithResultPagination(t *testing.T) {
+	store, _ := NewStore("")
+	firstResult := &testSuccessfulResult
+	secondResult := &testUnsuccessfulResult
+	store.Insert(&testService, firstResult)
+	store.Insert(&testService, secondResult)
+	// Can't be bothered dealing with timezone issues on the worker that runs the automated tests
+	firstResult.Timestamp = time.Time{}
+	secondResult.Timestamp = time.Time{}
+	serviceStatuses := store.GetAllServiceStatusesWithResultPagination(1, 20)
+	if len(serviceStatuses) != 1 {
+		t.Fatal("expected 1 service status")
+	}
+	actual, exists := serviceStatuses[util.ConvertGroupAndServiceToKey(testService.Group, testService.Name)]
+	if !exists {
+		t.Fatal("expected service status to exist")
+	}
+	if len(actual.Results) != 2 {
+		t.Error("expected 2 results, got", len(actual.Results))
+	}
+	if len(actual.Events) != 2 {
+		t.Error("expected 2 events, got", len(actual.Events))
+	}
+}
+
+func TestStore_DeleteAllServiceStatusesNotInKeys(t *testing.T) {
+	store, _ := NewStore("")
+	firstService := core.Service{Name: "service-1", Group: "group"}
+	secondService := core.Service{Name: "service-2", Group: "group"}
+	result := &testSuccessfulResult
+	store.Insert(&firstService, result)
+	store.Insert(&secondService, result)
+	if store.cache.Count() != 2 {
+		t.Errorf("expected cache to have 2 keys, got %d", store.cache.Count())
+	}
+	if store.GetServiceStatusByKey(util.ConvertGroupAndServiceToKey(firstService.Group, firstService.Name)) == nil {
+		t.Fatal("firstService should exist")
+	}
+	if store.GetServiceStatusByKey(util.ConvertGroupAndServiceToKey(secondService.Group, secondService.Name)) == nil {
+		t.Fatal("secondService should exist")
+	}
+	store.DeleteAllServiceStatusesNotInKeys([]string{util.ConvertGroupAndServiceToKey(firstService.Group, firstService.Name)})
+	if store.cache.Count() != 1 {
+		t.Fatalf("expected cache to have 1 keys, got %d", store.cache.Count())
+	}
+	if store.GetServiceStatusByKey(util.ConvertGroupAndServiceToKey(firstService.Group, firstService.Name)) == nil {
+		t.Error("secondService should've been deleted")
+	}
+	if store.GetServiceStatusByKey(util.ConvertGroupAndServiceToKey(secondService.Group, secondService.Name)) != nil {
+		t.Error("firstService should still exist")
+	}
+}
+
+func TestStore_Save(t *testing.T) {
+	files := []string{
+		"",
+		t.TempDir() + "/test.db",
+	}
+	for _, file := range files {
+		t.Run(file, func(t *testing.T) {
+			store, err := NewStore(file)
+			if err != nil {
+				t.Fatal("expected no error, got", err.Error())
+			}
+			err = store.Save()
+			if err != nil {
+				t.Fatal("expected no error, got", err.Error())
+			}
+		})
+	}
+}

storage/store/store.go

@@ -0,0 +1,38 @@
+package store
+
+import (
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage/store/memory"
+)
+
+// Store is the interface that each stores should implement
+type Store interface {
+	// GetAllAsJSON returns the JSON encoding of all monitored core.ServiceStatus
+	// with a subset of core.Result defined by the page and pageSize parameters
+	GetAllServiceStatusesWithResultPagination(page, pageSize int) map[string]*core.ServiceStatus
+
+	// GetServiceStatus returns the service status for a given service name in the given group
+	GetServiceStatus(groupName, serviceName string) *core.ServiceStatus
+
+	// GetServiceStatusByKey returns the service status for a given key
+	GetServiceStatusByKey(key string) *core.ServiceStatus
+
+	// Insert adds the observed result for the specified service into the store
+	Insert(service *core.Service, result *core.Result)
+
+	// DeleteAllServiceStatusesNotInKeys removes all ServiceStatus that are not within the keys provided
+	//
+	// Used to delete services that have been persisted but are no longer part of the configured services
+	DeleteAllServiceStatusesNotInKeys(keys []string) int
+
+	// Clear deletes everything from the store
+	Clear()
+
+	// Save persists the data if and where it needs to be persisted
+	Save() error
+}
+
+var (
+	// Validate interface implementation on compile
+	_ Store = (*memory.Store)(nil)
+)

storage/store/store_bench_test.go

@@ -0,0 +1,136 @@
+package store
+
+import (
+	"testing"
+	"time"
+
+	"github.com/TwinProduction/gatus/core"
+	"github.com/TwinProduction/gatus/storage/store/memory"
+)
+
+var (
+	firstCondition  = core.Condition("[STATUS] == 200")
+	secondCondition = core.Condition("[RESPONSE_TIME] < 500")
+	thirdCondition  = core.Condition("[CERTIFICATE_EXPIRATION] < 72h")
+
+	timestamp = time.Now()
+
+	testService = core.Service{
+		Name:                    "name",
+		Group:                   "group",
+		URL:                     "https://example.org/what/ever",
+		Method:                  "GET",
+		Body:                    "body",
+		Interval:                30 * time.Second,
+		Conditions:              []*core.Condition{&firstCondition, &secondCondition, &thirdCondition},
+		Alerts:                  nil,
+		Insecure:                false,
+		NumberOfFailuresInARow:  0,
+		NumberOfSuccessesInARow: 0,
+	}
+	testSuccessfulResult = core.Result{
+		Hostname:              "example.org",
+		IP:                    "127.0.0.1",
+		HTTPStatus:            200,
+		Body:                  []byte("body"),
+		Errors:                nil,
+		Connected:             true,
+		Success:               true,
+		Timestamp:             timestamp,
+		Duration:              150 * time.Millisecond,
+		CertificateExpiration: 10 * time.Hour,
+		ConditionResults: []*core.ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   true,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   true,
+			},
+		},
+	}
+	testUnsuccessfulResult = core.Result{
+		Hostname:              "example.org",
+		IP:                    "127.0.0.1",
+		HTTPStatus:            200,
+		Body:                  []byte("body"),
+		Errors:                []string{"error-1", "error-2"},
+		Connected:             true,
+		Success:               false,
+		Timestamp:             timestamp,
+		Duration:              750 * time.Millisecond,
+		CertificateExpiration: 10 * time.Hour,
+		ConditionResults: []*core.ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   false,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   false,
+			},
+		},
+	}
+)
+
+func BenchmarkStore_GetAllAsJSON(b *testing.B) {
+	memoryStore, err := memory.NewStore("")
+	if err != nil {
+		b.Fatal("failed to create store:", err.Error())
+	}
+	type Scenario struct {
+		Name  string
+		Store Store
+	}
+	scenarios := []Scenario{
+		{
+			Name:  "memory",
+			Store: memoryStore,
+		},
+	}
+	for _, scenario := range scenarios {
+		scenario.Store.Insert(&testService, &testSuccessfulResult)
+		scenario.Store.Insert(&testService, &testUnsuccessfulResult)
+		b.Run(scenario.Name, func(b *testing.B) {
+			for n := 0; n < b.N; n++ {
+				scenario.Store.GetAllServiceStatusesWithResultPagination(1, 20)
+			}
+			b.ReportAllocs()
+		})
+	}
+}
+
+func BenchmarkStore_Insert(b *testing.B) {
+	memoryStore, err := memory.NewStore("")
+	if err != nil {
+		b.Fatal("failed to create store:", err.Error())
+	}
+	type Scenario struct {
+		Name  string
+		Store Store
+	}
+	scenarios := []Scenario{
+		{
+			Name:  "memory",
+			Store: memoryStore,
+		},
+	}
+	for _, scenario := range scenarios {
+		b.Run(scenario.Name, func(b *testing.B) {
+			for n := 0; n < b.N; n++ {
+				scenario.Store.Insert(&testService, &testSuccessfulResult)
+				scenario.Store.Insert(&testService, &testUnsuccessfulResult)
+			}
+			b.ReportAllocs()
+		})
+	}
+}

util/key.go

@@ -0,0 +1,18 @@
+package util
+
+import "strings"
+
+// ConvertGroupAndServiceToKey converts a group and a service to a key
+func ConvertGroupAndServiceToKey(group, service string) string {
+	return sanitize(group) + "_" + sanitize(service)
+}
+
+func sanitize(s string) string {
+	s = strings.TrimSpace(strings.ToLower(s))
+	s = strings.ReplaceAll(s, "/", "-")
+	s = strings.ReplaceAll(s, "_", "-")
+	s = strings.ReplaceAll(s, ".", "-")
+	s = strings.ReplaceAll(s, ",", "-")
+	s = strings.ReplaceAll(s, " ", "-")
+	return s
+}

util/key_test.go

@@ -0,0 +1,36 @@
+package util
+
+import "testing"
+
+func TestConvertGroupAndServiceToKey(t *testing.T) {
+	type Scenario struct {
+		GroupName      string
+		ServiceName    string
+		ExpectedOutput string
+	}
+	scenarios := []Scenario{
+		{
+			GroupName:      "Core",
+			ServiceName:    "Front End",
+			ExpectedOutput: "core_front-end",
+		},
+		{
+			GroupName:      "Load balancers",
+			ServiceName:    "us-west-2",
+			ExpectedOutput: "load-balancers_us-west-2",
+		},
+		{
+			GroupName:      "a/b test",
+			ServiceName:    "a",
+			ExpectedOutput: "a-b-test_a",
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.ExpectedOutput, func(t *testing.T) {
+			output := ConvertGroupAndServiceToKey(scenario.GroupName, scenario.ServiceName)
+			if output != scenario.ExpectedOutput {
+				t.Errorf("Expected '%s', got '%s'", scenario.ExpectedOutput, output)
+			}
+		})
+	}
+}

vendor/github.com/TwinProduction/gocache/.gitattributes

@@ -0,0 +1 @@
+* text=lf

vendor/github.com/TwinProduction/gocache/.gitignore

@@ -0,0 +1 @@
+.idea

vendor/github.com/TwinProduction/gocache/Dockerfile

@@ -0,0 +1,20 @@
+# Build the go application into a binary
+FROM golang:alpine as builder
+WORKDIR /app
+ADD . ./
+RUN CGO_ENABLED=0 GOOS=linux go build -mod vendor -a -installsuffix cgo -o bin/gocache-server ./gocacheserver/main
+RUN apk --update add --no-cache ca-certificates
+
+FROM scratch
+ENV APP_HOME=/app
+ENV APP_DATA=/app/data
+ENV PORT=6379
+ENV MAX_CACHE_SIZE=100000
+ENV MAX_MEMORY_USAGE=0
+ENV AUTOSAVE="false"
+VOLUME ${APP_DATA}
+WORKDIR ${APP_HOME}
+COPY --from=builder /app/bin/gocache-server ./bin/gocache-server
+COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+EXPOSE ${PORT}
+ENTRYPOINT ["/app/bin/gocache-server"]

vendor/github.com/TwinProduction/gocache/LICENSE.md

@@ -0,0 +1,9 @@
+MIT License
+
+Copyright (c) 2020 TwinProduction
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

vendor/github.com/TwinProduction/gocache/Makefile

@@ -0,0 +1,24 @@
+db: docker-build
+dr: docker-run
+drmem: docker-run-max-memory-usage
+
+docker-build:
+	docker build --tag=gocache-server .
+
+docker-run:
+	docker run -p 6666:6379 -e AUTOSAVE=true -e MAX_CACHE_SIZE=0 --name gocache-server -d gocache-server
+
+docker-run-max-memory-usage:
+	docker run -p 6666:6379 -e AUTOSAVE=true -e MAX_CACHE_SIZE=0 -e MAX_MEMORY_USAGE=524288000 --name gocache-server -d gocache-server
+
+run:
+	PORT=6666 go run gocacheserver/main/server.go
+
+start-redis:
+	docker run -p 6379:6379 --name redis -d redis
+
+redis-benchmark:
+	redis-benchmark -p 6666 -t set,get -n 10000000 -r 200000 -q -P 512 -c 512
+
+memtier-benchmark:
+	memtier_benchmark --port 6666 --hide-histogram --key-maximum 100000 --ratio 1:1 --expiry-range 1-100 --key-pattern R:R --randomize -n 100000

vendor/github.com/TwinProduction/gocache/README.md

@@ -0,0 +1,476 @@
+# gocache
+
+![build](https://github.com/TwinProduction/gocache/workflows/build/badge.svg?branch=master) 
+[![Go Report Card](https://goreportcard.com/badge/github.com/TwinProduction/gocache)](https://goreportcard.com/report/github.com/TwinProduction/gocache)
+[![codecov](https://codecov.io/gh/TwinProduction/gocache/branch/master/graph/badge.svg)](https://codecov.io/gh/TwinProduction/gocache)
+[![Go version](https://img.shields.io/github/go-mod/go-version/TwinProduction/gocache.svg)](https://github.com/TwinProduction/gocache)
+[![Go Reference](https://pkg.go.dev/badge/github.com/TwinProduction/gocache.svg)](https://pkg.go.dev/github.com/TwinProduction/gocache)
+
+gocache is an easy-to-use, high-performance, lightweight and thread-safe (goroutine-safe) in-memory key-value cache 
+with support for LRU and FIFO eviction policies as well as expiration, bulk operations and even persistence to file.
+
+
+## Table of Contents
+
+- [Features](#features)
+- [Usage](#usage)
+  - [Initializing the cache](#initializing-the-cache)
+  - [Functions](#functions)
+  - [Examples](#examples)
+    - [Creating or updating an entry](#creating-or-updating-an-entry)
+    - [Getting an entry](#getting-an-entry)
+    - [Deleting an entry](#deleting-an-entry)
+    - [Complex example](#complex-example)
+- [Persistence](#persistence)
+  - [Limitations](#limitations)
+- [Eviction](#eviction)
+  - [MaxSize](#maxsize)
+  - [MaxMemoryUsage](#maxmemoryusage)
+- [Expiration](#expiration)
+- [Server](#server)
+- [Running the server with Docker](#running-the-server-with-docker)
+- [Performance](#performance)
+  - [Summary](#summary)
+  - [Results](#results)
+- [FAQ](#faq)
+  - [Why does the memory usage not go down?](#why-does-the-memory-usage-not-go-down)
+
+
+## Features
+gocache supports the following cache eviction policies: 
+- First in first out (FIFO)
+- Least recently used (LRU)
+
+It also supports cache entry TTL, which is both active and passive. Active expiration means that if you attempt 
+to retrieve a cache key that has already expired, it will delete it on the spot and the behavior will be as if
+the cache key didn't exist. As for passive expiration, there's a background task that will take care of deleting
+expired keys.
+
+It also includes what you'd expect from a cache, like bulk operations, persistence and patterns.
+
+While meant to be used as a library, there's a Redis-compatible cache server included. 
+See the [Server](#server) section. 
+It may also serve as a good reference to use in order to implement gocache in your own applications.
+
+
+## Usage
+```
+go get -u github.com/TwinProduction/gocache
+```
+
+### Initializing the cache
+```go
+cache := gocache.NewCache().WithMaxSize(1000).WithEvictionPolicy(gocache.LeastRecentlyUsed)
+```
+
+If you're planning on using expiration (`SetWithTTL` or `Expire`) and you want expired entries to be automatically deleted 
+in the background, make sure to start the janitor when you instantiate the cache:
+
+```go
+cache.StartJanitor()
+```
+
+### Functions
+| Function                          | Description |
+| --------------------------------- | ----------- |
+| WithMaxSize                       | Sets the max size of the cache. `gocache.NoMaxSize` means there is no limit. If not set, the default max size is `gocache.DefaultMaxSize`.
+| WithMaxMemoryUsage                | Sets the max memory usage of the cache. `gocache.NoMaxMemoryUsage` means there is no limit. The default behavior is to not evict based on memory usage.
+| WithEvictionPolicy                | Sets the eviction algorithm to be used when the cache reaches the max size. If not set, the default eviction policy is `gocache.FirstInFirstOut` (FIFO).
+| WithForceNilInterfaceOnNilPointer | Configures whether values with a nil pointer passed to write functions should be forcefully set to nil. Defaults to true.
+| StartJanitor                      | Starts the janitor, which is in charge of deleting expired cache entries in the background.
+| StopJanitor                       | Stops the janitor.
+| Set                               | Same as `SetWithTTL`, but with no expiration (`gocache.NoExpiration`)
+| SetAll                            | Same as `Set`, but in bulk
+| SetWithTTL                        | Creates or updates a cache entry with the given key, value and expiration time. If the max size after the aforementioned operation is above the configured max size, the tail will be evicted. Depending on the eviction policy, the tail is defined as the oldest 
+| Get                               | Gets a cache entry by its key.
+| GetByKeys                         | Gets a map of entries by their keys. The resulting map will contain all keys, even if some of the keys in the slice passed as parameter were not present in the cache.  
+| GetAll                            | Gets all cache entries.
+| GetKeysByPattern                  | Retrieves a slice of keys that matches a given pattern.
+| Delete                            | Removes a key from the cache.
+| DeleteAll                         | Removes multiple keys from the cache.
+| Count                             | Gets the size of the cache. This includes cache keys which may have already expired, but have not been removed yet.
+| Clear                             | Wipes the cache.
+| TTL                               | Gets the time until a cache key expires. 
+| Expire                            | Sets the expiration time of an existing cache key.
+| SaveToFile                        | Stores the content of the cache to a file so that it can be read using `ReadFromFile`. See [persistence](#persistence).
+| ReadFromFile                      | Populates the cache using a file created using `SaveToFile`. See [persistence](#persistence).
+
+For further documentation, please refer to [Go Reference](https://pkg.go.dev/github.com/TwinProduction/gocache)
+
+
+### Examples
+
+#### Creating or updating an entry
+```go
+cache.Set("key", "value") 
+cache.Set("key", 1)
+cache.Set("key", struct{ Text string }{Test: "value"})
+cache.SetWithTTL("key", []byte("value"), 24*time.Hour)
+```
+
+#### Getting an entry
+```go
+value, exists := cache.Get("key")
+```
+You can also get multiple entries by using `cache.GetByKeys([]string{"key1", "key2"})`
+
+#### Deleting an entry
+```go
+cache.Delete("key")
+```
+You can also delete multiple entries by using `cache.DeleteAll([]string{"key1", "key2"})`
+
+#### Complex example
+```go
+package main
+
+import (
+	"fmt"
+	"time"
+
+    "github.com/TwinProduction/gocache"
+)
+
+func main() {
+	cache := gocache.NewCache().WithEvictionPolicy(gocache.LeastRecentlyUsed).WithMaxSize(10000)
+	cache.StartJanitor() // Passively manages expired entries
+
+	cache.Set("key", "value")
+	cache.SetWithTTL("key-with-ttl", "value", 60*time.Minute)
+	cache.SetAll(map[string]interface{}{"k1": "v1", "k2": "v2", "k3": "v3"})
+
+	value, exists := cache.Get("key")
+	fmt.Printf("[Get] key=key; value=%s; exists=%v\n", value, exists)
+	for key, value := range cache.GetByKeys([]string{"k1", "k2", "k3"}) {
+		fmt.Printf("[GetByKeys] key=%s; value=%s\n", key, value)
+	}
+	for _, key := range cache.GetKeysByPattern("key*", 0) {
+		fmt.Printf("[GetKeysByPattern] key=%s\n", key)
+	}
+
+	fmt.Println("Cache size before persisting cache to file:", cache.Count())
+	err := cache.SaveToFile("cache.bak")
+	if err != nil {
+		panic(fmt.Sprintf("failed to persist cache to file: %s", err.Error()))
+	}
+
+	cache.Expire("key", time.Hour)
+	time.Sleep(500*time.Millisecond)
+	timeUntilExpiration, _ := cache.TTL("key")
+	fmt.Println("Number of minutes before 'key' expires:", int(timeUntilExpiration.Seconds()))
+
+	cache.Delete("key")
+	cache.DeleteAll([]string{"k1", "k2", "k3"})
+
+	fmt.Println("Cache size before restoring cache from file:", cache.Count())
+	_, err = cache.ReadFromFile("cache.bak")
+	if err != nil {
+		panic(fmt.Sprintf("failed to restore cache from file: %s", err.Error()))
+	}
+
+	fmt.Println("Cache size after restoring cache from file:", cache.Count())
+	cache.Clear()
+	fmt.Println("Cache size after clearing the cache:", cache.Count())
+}
+```
+
+<details>
+  <summary>Output</summary>
+
+```
+[Get] key=key; value=value; exists=true
+[GetByKeys] key=k2; value=v2
+[GetByKeys] key=k3; value=v3
+[GetByKeys] key=k1; value=v1
+[GetKeysByPattern] key=key
+[GetKeysByPattern] key=key-with-ttl
+Cache size before persisting cache to file: 5
+Number of minutes before 'key' expires: 3599
+Cache size before restoring cache from file: 1
+Cache size after restoring cache from file: 5
+Cache size after clearing the cache: 0
+```
+</details>
+
+
+## Persistence
+While gocache is an in-memory cache, you can still save the content of the cache in a file
+and vice versa.
+
+To save the content of the cache to a file:
+```go
+err := cache.SaveToFile(TestCacheFile)
+```
+
+To retrieve the content of the cache from a file:
+```go
+numberOfEntriesEvicted, err := newCache.ReadFromFile(TestCacheFile)
+```
+The `numberOfEntriesEvicted` will be non-zero only if the number of entries 
+in the file is higher than the cache's configured `MaxSize`.
+
+### Limitations
+While you can cache structs in memory out of the box, persisting structs to a file requires you to 
+**register the custom interfaces that your application uses with the `gob` package**.
+
+```go
+type YourCustomStruct struct {
+	A string
+	B int
+}
+
+// ...
+cache.Set("key", YourCustomStruct{A: "test", B: 123})
+```
+To persist your custom struct properly:
+```go
+gob.Register(YourCustomStruct{})
+cache.SaveToFile("gocache.bak")
+``` 
+The same applies for restoring the cache from a file:
+```go
+cache := NewCache()
+gob.Register(YourCustomStruct{})
+cache.ReadFromFile(TestCacheFile)
+value, _ := cache.Get("key")
+fmt.Println(value.(YourCustomStruct))
+```
+You only need to persist the struct once, so adding the following function in a file would suffice:
+```go
+func init() {
+    gob.Register(YourCustomStruct{})
+}
+```
+
+Failure to register your custom structs will prevent gocache from persisting and/or parsing the value of each keys that 
+use said custom structs.
+
+That being said, assuming that you're using gocache as a cache, this shouldn't create any bugs on your end, because
+every key that cannot be parsed are not populated into the cache by `ReadFromFile`.
+
+In other words, if you're falling back to a database or something similar when the cache doesn't have the key requested,
+you'll be fine.
+
+
+## Eviction
+
+### MaxSize
+Eviction by MaxSize is the default behavior, and is also the most efficient.
+
+The code below will create a cache that has a maximum size of 1000:
+```go
+cache := gocache.NewCache().WithMaxSize(1000)
+```
+This means that whenever an operation causes the total size of the cache to go above 1000, the tail will be evicted.
+
+### MaxMemoryUsage
+Eviction by MaxMemoryUsage is **disabled by default**, and is in alpha.
+
+The code below will create a cache that has a maximum memory usage of 50MB:
+```go
+cache := gocache.NewCache().WithMaxSize(0).WithMaxMemoryUsage(50*gocache.Megabyte)
+```
+This means that whenever an operation causes the total memory usage of the cache to go above 50MB, one or more tails
+will be evicted.
+
+Unlike evictions caused by reaching the MaxSize, evictions triggered by MaxMemoryUsage may lead to multiple entries
+being evicted in a row. The reason for this is that if, for instance, you had 100 entries of 0.1MB each and you suddenly added 
+a single entry of 10MB, 100 entries would need to be evicted to make enough space for that new big entry.
+
+It's very important to keep in mind that eviction by MaxMemoryUsage is approximate.
+
+**The only memory taken into consideration is the size of the cache, not the size of the entire application.**
+If you pass along 100MB worth of data in a matter of seconds, even though the cache's memory usage will remain
+under 50MB (or whatever you configure the MaxMemoryUsage to), the memory footprint generated by that 100MB will 
+still exist until the next GC cycle.
+
+As previously mentioned, this is a work in progress, and here's a list of the things you should keep in mind:
+- The memory usage of structs are a gross estimation and may not reflect the actual memory usage.
+- Native types (string, int, bool, []byte, etc.) are the most accurate for calculating the memory usage.
+- Adding an entry bigger than the configured MaxMemoryUsage will work, but it will evict all other entries.
+
+
+## Expiration
+There are two ways that the deletion of expired keys can take place:
+- Active
+- Passive
+
+**Active deletion of expired keys** happens when an attempt is made to access the value of a cache entry that expired. 
+`Get`, `GetByKeys` and `GetAll` are the only functions that can trigger active deletion of expired keys.
+
+**Passive deletion of expired keys** runs in the background and is managed by the janitor. 
+If you do not start the janitor, there will be no passive deletion of expired keys.
+
+
+## Server
+For the sake of convenience, a ready-to-go cache server is available 
+through the `gocacheserver` package. 
+
+The reason why the server is in a different package is because `gocache` limit its external dependencies to the strict 
+minimum (e.g. boltdb for persistence), however, rather than re-inventing the wheel, the server implementation uses
+redcon, which is a very good Redis server framework for Go.
+
+That way, those who desire to use gocache without the server will not add any extra dependencies
+as long as they don't import the `gocacheserver` package. 
+
+```go
+package main
+
+import (
+	"github.com/TwinProduction/gocache"
+	"github.com/TwinProduction/gocache/gocacheserver"
+)
+
+func main() {
+	cache := gocache.NewCache().WithEvictionPolicy(gocache.LeastRecentlyUsed).WithMaxSize(100000)
+	server := gocacheserver.NewServer(cache).WithPort(6379)
+	server.Start()
+}
+```
+
+Any Redis client should be able to interact with the server, though only the following instructions are supported:
+- [X] GET
+- [X] SET
+- [X] DEL
+- [X] PING
+- [X] QUIT
+- [X] INFO
+- [X] EXPIRE
+- [X] SETEX
+- [X] TTL
+- [X] FLUSHDB
+- [X] EXISTS
+- [X] ECHO
+- [X] MGET
+- [X] MSET
+- [X] SCAN (kind of - cursor is not currently supported)
+- [ ] KEYS
+
+
+## Running the server with Docker
+[![Docker pulls](https://img.shields.io/docker/pulls/twinproduction/gocache-server.svg)](https://cloud.docker.com/repository/docker/twinproduction/gocache-server)
+
+To build it locally, refer to the Makefile's `docker-build` and `docker-run` steps.
+
+Note that the server version of gocache is still under development.
+
+```
+docker run --name gocache-server -p 6379:6379 twinproduction/gocache-server
+```
+
+
+## Performance
+
+### Summary
+- **Set**: Both map and gocache have the same performance.
+- **Get**: Map is faster than gocache.
+
+This is because gocache keeps track of the head and the tail for eviction and expiration/TTL. 
+
+Ultimately, the difference is negligible. 
+
+We could add a way to disable eviction or disable expiration altogether just to match the map's performance, 
+but if you're looking into using a library like gocache, odds are, you want more than just a map.
+
+
+### Results
+| key    | value    |
+|:------ |:-------- |
+| goos   | windows  |
+| goarch | amd64    |
+| cpu    | i7-9700K |
+| mem    | 32G DDR4 |
+
+```
+// Normal map
+BenchmarkMap_Get
+BenchmarkMap_Get-8                                                              46087372  26.7 ns/op
+BenchmarkMap_Set                                                                   
+BenchmarkMap_Set/small_value-8                                                   3841911   389 ns/op
+BenchmarkMap_Set/medium_value-8                                                  3887074   391 ns/op
+BenchmarkMap_Set/large_value-8                                                   3921956   393 ns/op
+// Gocache                                                                         
+BenchmarkCache_Get                                                                 
+BenchmarkCache_Get/FirstInFirstOut-8                                            27273036  46.4 ns/op
+BenchmarkCache_Get/LeastRecentlyUsed-8                                          26648248  46.3 ns/op
+BenchmarkCache_Set                                                              
+BenchmarkCache_Set/FirstInFirstOut_small_value-8                                 2919584   405 ns/op
+BenchmarkCache_Set/FirstInFirstOut_medium_value-8                                2990841   391 ns/op
+BenchmarkCache_Set/FirstInFirstOut_large_value-8                                 2970513   391 ns/op
+BenchmarkCache_Set/LeastRecentlyUsed_small_value-8                               2962939   402 ns/op
+BenchmarkCache_Set/LeastRecentlyUsed_medium_value-8                              2962963   390 ns/op
+BenchmarkCache_Set/LeastRecentlyUsed_large_value-8                               2962928   394 ns/op
+BenchmarkCache_SetUsingMaxMemoryUsage                                           
+BenchmarkCache_SetUsingMaxMemoryUsage/small_value-8                              2683356   447 ns/op
+BenchmarkCache_SetUsingMaxMemoryUsage/medium_value-8                             2637578   441 ns/op
+BenchmarkCache_SetUsingMaxMemoryUsage/large_value-8                              2672434   443 ns/op
+BenchmarkCache_SetWithMaxSize                                                   
+BenchmarkCache_SetWithMaxSize/100_small_value-8                                  4782966   252 ns/op
+BenchmarkCache_SetWithMaxSize/10000_small_value-8                                4067967   296 ns/op
+BenchmarkCache_SetWithMaxSize/100000_small_value-8                               3762055   328 ns/op
+BenchmarkCache_SetWithMaxSize/100_medium_value-8                                 4760479   252 ns/op
+BenchmarkCache_SetWithMaxSize/10000_medium_value-8                               4081050   295 ns/op
+BenchmarkCache_SetWithMaxSize/100000_medium_value-8                              3785050   330 ns/op
+BenchmarkCache_SetWithMaxSize/100_large_value-8                                  4732909   254 ns/op
+BenchmarkCache_SetWithMaxSize/10000_large_value-8                                4079533   297 ns/op
+BenchmarkCache_SetWithMaxSize/100000_large_value-8                               3712820   331 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU                                             
+BenchmarkCache_SetWithMaxSizeAndLRU/100_small_value-8                            4761732   254 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU/10000_small_value-8                          4084474   296 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU/100000_small_value-8                         3761402   329 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU/100_medium_value-8                           4783075   254 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU/10000_medium_value-8                         4103980   296 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU/100000_medium_value-8                        3646023   331 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU/100_large_value-8                            4779025   254 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU/10000_large_value-8                          4096192   296 ns/op
+BenchmarkCache_SetWithMaxSizeAndLRU/100000_large_value-8                         3726823   331 ns/op
+BenchmarkCache_GetSetMultipleConcurrent                                         
+BenchmarkCache_GetSetMultipleConcurrent-8                                         707142  1698 ns/op
+BenchmarkCache_GetSetConcurrentWithFrequentEviction
+BenchmarkCache_GetSetConcurrentWithFrequentEviction/FirstInFirstOut-8            3616256   334 ns/op
+BenchmarkCache_GetSetConcurrentWithFrequentEviction/LeastRecentlyUsed-8          3636367   331 ns/op
+BenchmarkCache_GetConcurrentWithLRU                                              
+BenchmarkCache_GetConcurrentWithLRU/FirstInFirstOut-8                            4405557   268 ns/op
+BenchmarkCache_GetConcurrentWithLRU/LeastRecentlyUsed-8                          4445475   269 ns/op
+BenchmarkCache_WithForceNilInterfaceOnNilPointer
+BenchmarkCache_WithForceNilInterfaceOnNilPointer/true_with_nil_struct_pointer-8  6184591   191 ns/op
+BenchmarkCache_WithForceNilInterfaceOnNilPointer/true-8                          6090482   191 ns/op
+BenchmarkCache_WithForceNilInterfaceOnNilPointer/false_with_nil_struct_pointer-8 6184629   187 ns/op
+BenchmarkCache_WithForceNilInterfaceOnNilPointer/false-8                         6281781   186 ns/op
+(Trimmed "BenchmarkCache_" for readability)
+WithForceNilInterfaceOnNilPointerWithConcurrency
+WithForceNilInterfaceOnNilPointerWithConcurrency/true_with_nil_struct_pointer-8  4379564   268 ns/op
+WithForceNilInterfaceOnNilPointerWithConcurrency/true-8                          4379558   265 ns/op
+WithForceNilInterfaceOnNilPointerWithConcurrency/false_with_nil_struct_pointer-8 4444456   261 ns/op
+WithForceNilInterfaceOnNilPointerWithConcurrency/false-8                         4493896   262 ns/op
+```
+
+
+## FAQ
+
+### Why does the memory usage not go down?
+
+> **NOTE**: As of Go 1.16, this will no longer apply. See [golang/go#42330](https://github.com/golang/go/issues/42330)
+
+By default, Go uses `MADV_FREE` if the kernel supports it to release memory, which is significantly more efficient 
+than using `MADV_DONTNEED`. Unfortunately, this means that RSS doesn't go down unless the OS actually needs the 
+memory. 
+
+Technically, the memory _is_ available to the kernel, even if it shows a high memory usage, but the OS will only
+use that memory if it needs to. In the case that the OS does need the freed memory, the RSS will go down and you'll
+notice the memory usage lowering.
+
+[reference](https://github.com/golang/go/issues/33376#issuecomment-666455792)
+
+You can reproduce this by following the steps below:
+- Start gocacheserver
+- Note the memory usage
+- Create 500k keys
+- Note the memory usage
+- Flush the cache
+- Note that the memory usage has not decreased, despite the cache being empty.
+
+**Substituting gocache for a normal map will yield the same result.**
+
+If the released memory still appearing as used is a problem for you, 
+you can set the environment variable `GODEBUG` to `madvdontneed=1`.

vendor/github.com/TwinProduction/gocache/entry.go

@@ -0,0 +1,108 @@
+package gocache
+
+import (
+	"fmt"
+	"time"
+	"unsafe"
+)
+
+// Entry is a cache entry
+type Entry struct {
+	// Key is the name of the cache entry
+	Key string
+
+	// Value is the value of the cache entry
+	Value interface{}
+
+	// RelevantTimestamp is the variable used to store either:
+	// - creation timestamp, if the Cache's EvictionPolicy is FirstInFirstOut
+	// - last access timestamp, if the Cache's EvictionPolicy is LeastRecentlyUsed
+	//
+	// Note that updating an existing entry will also update this value
+	RelevantTimestamp time.Time
+
+	// Expiration is the unix time in nanoseconds at which the entry will expire (-1 means no expiration)
+	Expiration int64
+
+	next     *Entry
+	previous *Entry
+}
+
+// Accessed updates the Entry's RelevantTimestamp to now
+func (entry *Entry) Accessed() {
+	entry.RelevantTimestamp = time.Now()
+}
+
+// Expired returns whether the Entry has expired
+func (entry Entry) Expired() bool {
+	if entry.Expiration > 0 {
+		if time.Now().UnixNano() > entry.Expiration {
+			return true
+		}
+	}
+	return false
+}
+
+// SizeInBytes returns the size of an entry in bytes, approximately.
+func (entry *Entry) SizeInBytes() int {
+	return toBytes(entry.Key) + toBytes(entry.Value) + 32
+}
+
+func toBytes(value interface{}) int {
+	switch value.(type) {
+	case string:
+		return int(unsafe.Sizeof(value)) + len(value.(string))
+	case int8, uint8, bool:
+		return int(unsafe.Sizeof(value)) + 1
+	case int16, uint16:
+		return int(unsafe.Sizeof(value)) + 2
+	case int32, uint32, float32, complex64:
+		return int(unsafe.Sizeof(value)) + 4
+	case int64, uint64, int, uint, float64, complex128:
+		return int(unsafe.Sizeof(value)) + 8
+	case []interface{}:
+		size := 0
+		for _, v := range value.([]interface{}) {
+			size += toBytes(v)
+		}
+		return int(unsafe.Sizeof(value)) + size
+	case []string:
+		size := 0
+		for _, v := range value.([]string) {
+			size += toBytes(v)
+		}
+		return int(unsafe.Sizeof(value)) + size
+	case []int8:
+		return int(unsafe.Sizeof(value)) + len(value.([]int8))
+	case []uint8:
+		return int(unsafe.Sizeof(value)) + len(value.([]uint8))
+	case []bool:
+		return int(unsafe.Sizeof(value)) + len(value.([]bool))
+	case []int16:
+		return int(unsafe.Sizeof(value)) + (len(value.([]int16)) * 2)
+	case []uint16:
+		return int(unsafe.Sizeof(value)) + (len(value.([]uint16)) * 2)
+	case []int32:
+		return int(unsafe.Sizeof(value)) + (len(value.([]int32)) * 4)
+	case []uint32:
+		return int(unsafe.Sizeof(value)) + (len(value.([]uint32)) * 4)
+	case []float32:
+		return int(unsafe.Sizeof(value)) + (len(value.([]float32)) * 4)
+	case []complex64:
+		return int(unsafe.Sizeof(value)) + (len(value.([]complex64)) * 4)
+	case []int64:
+		return int(unsafe.Sizeof(value)) + (len(value.([]int64)) * 8)
+	case []uint64:
+		return int(unsafe.Sizeof(value)) + (len(value.([]uint64)) * 8)
+	case []int:
+		return int(unsafe.Sizeof(value)) + (len(value.([]int)) * 8)
+	case []uint:
+		return int(unsafe.Sizeof(value)) + (len(value.([]uint)) * 8)
+	case []float64:
+		return int(unsafe.Sizeof(value)) + (len(value.([]float64)) * 8)
+	case []complex128:
+		return int(unsafe.Sizeof(value)) + (len(value.([]complex128)) * 8)
+	default:
+		return int(unsafe.Sizeof(value)) + len(fmt.Sprintf("%v", value))
+	}
+}

vendor/github.com/TwinProduction/gocache/go.mod

@@ -0,0 +1,11 @@
+module github.com/TwinProduction/gocache
+
+go 1.15
+
+require (
+	github.com/go-redis/redis v6.15.9+incompatible
+	github.com/onsi/ginkgo v1.14.1 // indirect
+	github.com/onsi/gomega v1.10.2 // indirect
+	github.com/tidwall/redcon v1.3.2
+	go.etcd.io/bbolt v1.3.5
+)

vendor/github.com/TwinProduction/gocache/go.sum

@@ -0,0 +1,67 @@
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vendor/github.com/TwinProduction/gocache/gocache.go

@@ -0,0 +1,567 @@
+package gocache
+
+import (
+	"errors"
+	"reflect"
+	"sync"
+	"time"
+)
+
+var (
+	Debug = false
+)
+
+const (
+	// NoMaxSize means that the cache has no maximum number of entries in the cache
+	// Setting Cache.maxSize to this value also means there will be no eviction
+	NoMaxSize = 0
+
+	// NoMaxMemoryUsage means that the cache has no maximum number of entries in the cache
+	NoMaxMemoryUsage = 0
+
+	// DefaultMaxSize is the max size set if no max size is specified
+	DefaultMaxSize = 100000
+
+	// NoExpiration is the value that must be used as TTL to specify that the given key should never expire
+	NoExpiration = -1
+
+	Kilobyte = 1024
+	Megabyte = 1024 * Kilobyte
+	Gigabyte = 1024 * Megabyte
+)
+
+var (
+	ErrKeyDoesNotExist       = errors.New("key does not exist")
+	ErrKeyHasNoExpiration    = errors.New("key has no expiration")
+	ErrJanitorAlreadyRunning = errors.New("janitor is already running")
+)
+
+// Cache is the core struct of gocache which contains the data as well as all relevant configuration fields
+type Cache struct {
+	// maxSize is the maximum amount of entries that can be in the cache at any given time
+	// By default, this is set to DefaultMaxSize
+	maxSize int
+
+	// maxMemoryUsage is the maximum amount of memory that can be taken up by the cache at any time
+	// By default, this is set to NoMaxMemoryUsage, meaning that the default behavior is to not evict
+	// based on maximum memory usage
+	maxMemoryUsage int
+
+	// evictionPolicy is the eviction policy
+	evictionPolicy EvictionPolicy
+
+	// stats is the object that contains cache statistics/metrics
+	stats *Statistics
+
+	// entries is the content of the cache
+	entries map[string]*Entry
+
+	// mutex is the lock for making concurrent operations on the cache
+	mutex sync.RWMutex
+
+	// head is the cache entry at the head of the cache
+	head *Entry
+
+	// tail is the last cache node and also the next entry that will be evicted
+	tail *Entry
+
+	// stopJanitor is the channel used to stop the janitor
+	stopJanitor chan bool
+
+	// memoryUsage is the approximate memory usage of the cache (dataset only) in bytes
+	memoryUsage int
+
+	// forceNilInterfaceOnNilPointer determines whether all Set-like functions should set a value as nil if the
+	// interface passed has a nil value but not a nil type.
+	//
+	// By default, interfaces are only nil when both their type and value is nil.
+	// This means that when you pass a pointer to a nil value, the type of the interface
+	// will still show as nil, which means that if you don't cast the interface after
+	// retrieving it, a nil check will return that the value is not false.
+	forceNilInterfaceOnNilPointer bool
+}
+
+// MaxSize returns the maximum amount of keys that can be present in the cache before
+// new entries trigger the eviction of the tail
+func (cache *Cache) MaxSize() int {
+	return cache.maxSize
+}
+
+// MaxMemoryUsage returns the configured maxMemoryUsage of the cache
+func (cache *Cache) MaxMemoryUsage() int {
+	return cache.maxMemoryUsage
+}
+
+// EvictionPolicy returns the EvictionPolicy of the Cache
+func (cache *Cache) EvictionPolicy() EvictionPolicy {
+	return cache.evictionPolicy
+}
+
+// Stats returns statistics from the cache
+func (cache *Cache) Stats() Statistics {
+	cache.mutex.RLock()
+	stats := Statistics{
+		EvictedKeys: cache.stats.EvictedKeys,
+		ExpiredKeys: cache.stats.ExpiredKeys,
+		Hits:        cache.stats.Hits,
+		Misses:      cache.stats.Misses,
+	}
+	cache.mutex.RUnlock()
+	return stats
+}
+
+// MemoryUsage returns the current memory usage of the cache's dataset in bytes
+// If MaxMemoryUsage is set to NoMaxMemoryUsage, this will return 0
+func (cache *Cache) MemoryUsage() int {
+	return cache.memoryUsage
+}
+
+// WithMaxSize sets the maximum amount of entries that can be in the cache at any given time
+// A maxSize of 0 or less means infinite
+func (cache *Cache) WithMaxSize(maxSize int) *Cache {
+	if maxSize < 0 {
+		maxSize = NoMaxSize
+	}
+	if maxSize != NoMaxSize && cache.Count() == 0 {
+		cache.entries = make(map[string]*Entry, maxSize)
+	}
+	cache.maxSize = maxSize
+	return cache
+}
+
+// WithMaxMemoryUsage sets the maximum amount of memory that can be used by the cache at any given time
+//
+// NOTE: This is approximate.
+//
+// Setting this to NoMaxMemoryUsage will disable eviction by memory usage
+func (cache *Cache) WithMaxMemoryUsage(maxMemoryUsageInBytes int) *Cache {
+	if maxMemoryUsageInBytes < 0 {
+		maxMemoryUsageInBytes = NoMaxMemoryUsage
+	}
+	cache.maxMemoryUsage = maxMemoryUsageInBytes
+	return cache
+}
+
+// WithEvictionPolicy sets eviction algorithm.
+// Defaults to FirstInFirstOut (FIFO)
+func (cache *Cache) WithEvictionPolicy(policy EvictionPolicy) *Cache {
+	cache.evictionPolicy = policy
+	return cache
+}
+
+// WithForceNilInterfaceOnNilPointer sets whether all Set-like functions should set a value as nil if the
+// interface passed has a nil value but not a nil type.
+//
+// In Go, an interface is only nil if both its type and value are nil, which means that a nil pointer
+// (e.g. (*Struct)(nil)) will retain its attribution to the type, and the unmodified value returned from
+// Cache.Get, for instance, would return false when compared with nil if this option is set to false.
+//
+// We can bypass this by detecting if the interface's value is nil and setting it to nil rather than
+// a nil pointer, which will make the value returned from Cache.Get return true when compared with nil.
+// This is exactly what passing true to WithForceNilInterfaceOnNilPointer does, and it's also the default behavior.
+//
+// Alternatively, you may pass false to WithForceNilInterfaceOnNilPointer, which will mean that you'll have
+// to cast the value returned from Cache.Get to its original type to check for whether the pointer returned
+// is nil or not.
+//
+// If set to true:
+//     cache := gocache.NewCache().WithForceNilInterfaceOnNilPointer(true)
+//     cache.Set("key", (*Struct)(nil))
+//     value, _ := cache.Get("key")
+//     // the following returns true, because the interface{} was forcefully set to nil
+//     if value == nil {}
+//     // the following will panic, because the value has been casted to its type (which is nil)
+//     if value.(*Struct) == nil {}
+//
+// If set to false:
+//     cache := gocache.NewCache().WithForceNilInterfaceOnNilPointer(false)
+//     cache.Set("key", (*Struct)(nil))
+//     value, _ := cache.Get("key")
+//     // the following returns false, because the interface{} returned has a non-nil type (*Struct)
+//     if value == nil {}
+//     // the following returns true, because the value has been casted to its type
+//     if value.(*Struct) == nil {}
+//
+// In other words, if set to true, you do not need to cast the value returned from the cache to
+// to check if the value is nil.
+//
+// Defaults to true
+func (cache *Cache) WithForceNilInterfaceOnNilPointer(forceNilInterfaceOnNilPointer bool) *Cache {
+	cache.forceNilInterfaceOnNilPointer = forceNilInterfaceOnNilPointer
+	return cache
+}
+
+// NewCache creates a new Cache
+//
+// Should be used in conjunction with Cache.WithMaxSize, Cache.WithMaxMemoryUsage and/or Cache.WithEvictionPolicy
+//     gocache.NewCache().WithMaxSize(10000).WithEvictionPolicy(gocache.LeastRecentlyUsed)
+//
+func NewCache() *Cache {
+	return &Cache{
+		maxSize:                       DefaultMaxSize,
+		evictionPolicy:                FirstInFirstOut,
+		stats:                         &Statistics{},
+		entries:                       make(map[string]*Entry),
+		mutex:                         sync.RWMutex{},
+		stopJanitor:                   nil,
+		forceNilInterfaceOnNilPointer: true,
+	}
+}
+
+// Set creates or updates a key with a given value
+func (cache *Cache) Set(key string, value interface{}) {
+	cache.SetWithTTL(key, value, NoExpiration)
+}
+
+// SetWithTTL creates or updates a key with a given value and sets an expiration time (-1 is NoExpiration)
+//
+// The TTL provided must be greater than 0, or NoExpiration (-1). If a negative value that isn't -1 (NoExpiration) is
+// provided, the entry will not be created if the key doesn't exist
+func (cache *Cache) SetWithTTL(key string, value interface{}, ttl time.Duration) {
+	// An interface is only nil if both its value and its type are nil, however, passing a nil pointer as an interface{}
+	// means that the interface itself is not nil, because the interface value is nil but not the type.
+	if cache.forceNilInterfaceOnNilPointer {
+		if value != nil && (reflect.ValueOf(value).Kind() == reflect.Ptr && reflect.ValueOf(value).IsNil()) {
+			value = nil
+		}
+	}
+	cache.mutex.Lock()
+	entry, ok := cache.get(key)
+	if !ok {
+		// A negative TTL that isn't -1 (NoExpiration) or 0 is an entry that will expire instantly,
+		// so might as well just not create it in the first place
+		if ttl != NoExpiration && ttl < 1 {
+			cache.mutex.Unlock()
+			return
+		}
+		// Cache entry doesn't exist, so we have to create a new one
+		entry = &Entry{
+			Key:               key,
+			Value:             value,
+			RelevantTimestamp: time.Now(),
+			previous:          cache.head,
+		}
+		if cache.head == nil {
+			cache.tail = entry
+		} else {
+			cache.head.next = entry
+		}
+		cache.head = entry
+		cache.entries[key] = entry
+		if cache.maxMemoryUsage != NoMaxMemoryUsage {
+			cache.memoryUsage += entry.SizeInBytes()
+		}
+	} else {
+		// A negative TTL that isn't -1 (NoExpiration) or 0 is an entry that will expire instantly,
+		// so might as well just delete it immediately instead of updating it
+		if ttl != NoExpiration && ttl < 1 {
+			cache.delete(key)
+			cache.mutex.Unlock()
+			return
+		}
+		if cache.maxMemoryUsage != NoMaxMemoryUsage {
+			// Substract the old entry from the cache's memoryUsage
+			cache.memoryUsage -= entry.SizeInBytes()
+		}
+		// Update existing entry's value
+		entry.Value = value
+		entry.RelevantTimestamp = time.Now()
+		if cache.maxMemoryUsage != NoMaxMemoryUsage {
+			// Add the memory usage of the new entry to the cache's memoryUsage
+			cache.memoryUsage += entry.SizeInBytes()
+		}
+		// Because we just updated the entry, we need to move it back to HEAD
+		cache.moveExistingEntryToHead(entry)
+	}
+	if ttl != NoExpiration {
+		entry.Expiration = time.Now().Add(ttl).UnixNano()
+	} else {
+		entry.Expiration = NoExpiration
+	}
+	// If the cache doesn't have a maxSize/maxMemoryUsage, then there's no point checking if we need to evict
+	// an entry, so we'll just return now
+	if cache.maxSize == NoMaxSize && cache.maxMemoryUsage == NoMaxMemoryUsage {
+		cache.mutex.Unlock()
+		return
+	}
+	// If there's a maxSize and the cache has more entries than the maxSize, evict
+	if cache.maxSize != NoMaxSize && len(cache.entries) > cache.maxSize {
+		cache.evict()
+	}
+	// If there's a maxMemoryUsage and the memoryUsage is above the maxMemoryUsage, evict
+	if cache.maxMemoryUsage != NoMaxMemoryUsage && cache.memoryUsage > cache.maxMemoryUsage {
+		for cache.memoryUsage > cache.maxMemoryUsage && len(cache.entries) > 0 {
+			cache.evict()
+		}
+	}
+	cache.mutex.Unlock()
+}
+
+// SetAll creates or updates multiple values
+func (cache *Cache) SetAll(entries map[string]interface{}) {
+	for key, value := range entries {
+		cache.SetWithTTL(key, value, NoExpiration)
+	}
+}
+
+// Get retrieves an entry using the key passed as parameter
+// If there is no such entry, the value returned will be nil and the boolean will be false
+// If there is an entry, the value returned will be the value cached and the boolean will be true
+func (cache *Cache) Get(key string) (interface{}, bool) {
+	cache.mutex.Lock()
+	entry, ok := cache.get(key)
+	if !ok {
+		cache.mutex.Unlock()
+		cache.stats.Misses++
+		return nil, false
+	}
+	if entry.Expired() {
+		cache.stats.ExpiredKeys++
+		cache.delete(key)
+		cache.mutex.Unlock()
+		return nil, false
+	}
+	cache.stats.Hits++
+	if cache.evictionPolicy == LeastRecentlyUsed {
+		entry.Accessed()
+		if cache.head == entry {
+			cache.mutex.Unlock()
+			return entry.Value, true
+		}
+		// Because the eviction policy is LRU, we need to move the entry back to HEAD
+		cache.moveExistingEntryToHead(entry)
+	}
+	cache.mutex.Unlock()
+	return entry.Value, true
+}
+
+// GetValue retrieves an entry using the key passed as parameter
+// Unlike Get, this function only returns the value
+func (cache *Cache) GetValue(key string) interface{} {
+	value, _ := cache.Get(key)
+	return value
+}
+
+// GetByKeys retrieves multiple entries using the keys passed as parameter
+// All keys are returned in the map, regardless of whether they exist or not, however, entries that do not exist in the
+// cache will return nil, meaning that there is no way of determining whether a key genuinely has the value nil, or
+// whether it doesn't exist in the cache using only this function.
+func (cache *Cache) GetByKeys(keys []string) map[string]interface{} {
+	entries := make(map[string]interface{})
+	for _, key := range keys {
+		entries[key], _ = cache.Get(key)
+	}
+	return entries
+}
+
+// GetAll retrieves all cache entries
+//
+// If the eviction policy is LeastRecentlyUsed, note that unlike Get and GetByKeys, this does not update the last access
+// timestamp. The reason for this is that since all cache entries will be accessed, updating the last access timestamp
+// would provide very little benefit while harming the ability to accurately determine the next key that will be evicted
+//
+// You should probably avoid using this if you have a lot of entries.
+//
+// GetKeysByPattern is a good alternative if you want to retrieve entries that you do not have the key for, as it only
+// retrieves the keys and does not trigger active eviction and has a parameter for setting a limit to the number of keys
+// you wish to retrieve.
+func (cache *Cache) GetAll() map[string]interface{} {
+	entries := make(map[string]interface{})
+	cache.mutex.Lock()
+	for key, entry := range cache.entries {
+		if entry.Expired() {
+			cache.delete(key)
+			continue
+		}
+		entries[key] = entry.Value
+	}
+	cache.stats.Hits += uint64(len(entries))
+	cache.mutex.Unlock()
+	return entries
+}
+
+// GetKeysByPattern retrieves a slice of keys that match a given pattern
+// If the limit is set to 0, the entire cache will be searched for matching keys.
+// If the limit is above 0, the search will stop once the specified number of matching keys have been found.
+//
+// e.g.
+//     cache.GetKeysByPattern("*some*", 0) will return all keys containing "some" in them
+//     cache.GetKeysByPattern("*some*", 5) will return 5 keys (or less) containing "some" in them
+//
+// Note that GetKeysByPattern does not trigger active evictions, nor does it count as accessing the entry, the latter
+// only applying if the cache uses the LeastRecentlyUsed eviction policy.
+// The reason for that behavior is that these two (active eviction and access) only applies when you access the value
+// of the cache entry, and this function only returns the keys.
+func (cache *Cache) GetKeysByPattern(pattern string, limit int) []string {
+	var matchingKeys []string
+	cache.mutex.Lock()
+	for key, value := range cache.entries {
+		if value.Expired() {
+			continue
+		}
+		if MatchPattern(pattern, key) {
+			matchingKeys = append(matchingKeys, key)
+			if limit > 0 && len(matchingKeys) >= limit {
+				break
+			}
+		}
+	}
+	cache.mutex.Unlock()
+	return matchingKeys
+}
+
+// Delete removes a key from the cache
+//
+// Returns false if the key did not exist.
+func (cache *Cache) Delete(key string) bool {
+	cache.mutex.Lock()
+	ok := cache.delete(key)
+	cache.mutex.Unlock()
+	return ok
+}
+
+// DeleteAll deletes multiple entries based on the keys passed as parameter
+//
+// Returns the number of keys deleted
+func (cache *Cache) DeleteAll(keys []string) int {
+	numberOfKeysDeleted := 0
+	cache.mutex.Lock()
+	for _, key := range keys {
+		if cache.delete(key) {
+			numberOfKeysDeleted++
+		}
+	}
+	cache.mutex.Unlock()
+	return numberOfKeysDeleted
+}
+
+// Count returns the total amount of entries in the cache, regardless of whether they're expired or not
+func (cache *Cache) Count() int {
+	cache.mutex.RLock()
+	count := len(cache.entries)
+	cache.mutex.RUnlock()
+	return count
+}
+
+// Clear deletes all entries from the cache
+func (cache *Cache) Clear() {
+	cache.mutex.Lock()
+	cache.entries = make(map[string]*Entry)
+	cache.memoryUsage = 0
+	cache.head = nil
+	cache.tail = nil
+	cache.mutex.Unlock()
+}
+
+// TTL returns the time until the cache entry specified by the key passed as parameter
+// will be deleted.
+func (cache *Cache) TTL(key string) (time.Duration, error) {
+	cache.mutex.RLock()
+	entry, ok := cache.get(key)
+	cache.mutex.RUnlock()
+	if !ok {
+		return 0, ErrKeyDoesNotExist
+	}
+	if entry.Expiration == NoExpiration {
+		return 0, ErrKeyHasNoExpiration
+	}
+	timeUntilExpiration := time.Until(time.Unix(0, entry.Expiration))
+	if timeUntilExpiration < 0 {
+		// The key has already expired but hasn't been deleted yet.
+		// From the client's perspective, this means that the cache entry doesn't exist
+		return 0, ErrKeyDoesNotExist
+	}
+	return timeUntilExpiration, nil
+}
+
+// Expire sets a key's expiration time
+//
+// A TTL of -1 means that the key will never expire
+// A TTL of 0 means that the key will expire immediately
+// If using LRU, note that this does not reset the position of the key
+//
+// Returns true if the cache key exists and has had its expiration time altered
+func (cache *Cache) Expire(key string, ttl time.Duration) bool {
+	entry, ok := cache.get(key)
+	if !ok || entry.Expired() {
+		return false
+	}
+	if ttl != NoExpiration {
+		entry.Expiration = time.Now().Add(ttl).UnixNano()
+	} else {
+		entry.Expiration = NoExpiration
+	}
+	return true
+}
+
+// get retrieves an entry using the key passed as parameter, but unlike Get, it doesn't update the access time or
+// move the position of the entry to the head
+func (cache *Cache) get(key string) (*Entry, bool) {
+	entry, ok := cache.entries[key]
+	return entry, ok
+}
+
+func (cache *Cache) delete(key string) bool {
+	entry, ok := cache.entries[key]
+	if ok {
+		if cache.maxMemoryUsage != NoMaxMemoryUsage {
+			cache.memoryUsage -= entry.SizeInBytes()
+		}
+		cache.removeExistingEntryReferences(entry)
+		delete(cache.entries, key)
+	}
+	return ok
+}
+
+// moveExistingEntryToHead replaces the current cache head for an existing entry
+func (cache *Cache) moveExistingEntryToHead(entry *Entry) {
+	if !(entry == cache.head && entry == cache.tail) {
+		cache.removeExistingEntryReferences(entry)
+	}
+	if entry != cache.head {
+		entry.previous = cache.head
+		entry.next = nil
+		if cache.head != nil {
+			cache.head.next = entry
+		}
+		cache.head = entry
+	}
+}
+
+// removeExistingEntryReferences modifies the next and previous reference of an existing entry and re-links
+// the next and previous entry accordingly, as well as the cache head or/and the cache tail if necessary.
+// Note that it does not remove the entry from the cache, only the references.
+func (cache *Cache) removeExistingEntryReferences(entry *Entry) {
+	if cache.tail == entry && cache.head == entry {
+		cache.tail = nil
+		cache.head = nil
+	} else if cache.tail == entry {
+		cache.tail = cache.tail.next
+	} else if cache.head == entry {
+		cache.head = cache.head.previous
+	}
+	if entry.previous != nil {
+		entry.previous.next = entry.next
+	}
+	if entry.next != nil {
+		entry.next.previous = entry.previous
+	}
+	entry.next = nil
+	entry.previous = nil
+}
+
+// evict removes the tail from the cache
+func (cache *Cache) evict() {
+	if cache.tail == nil || len(cache.entries) == 0 {
+		return
+	}
+	if cache.tail != nil {
+		oldTail := cache.tail
+		cache.removeExistingEntryReferences(oldTail)
+		delete(cache.entries, oldTail.Key)
+		if cache.maxMemoryUsage != NoMaxMemoryUsage {
+			cache.memoryUsage -= oldTail.SizeInBytes()
+		}
+		cache.stats.EvictedKeys++
+	}
+}

vendor/github.com/TwinProduction/gocache/janitor.go

@@ -0,0 +1,140 @@
+package gocache
+
+import (
+	"log"
+	"time"
+)
+
+const (
+	// JanitorShiftTarget is the target number of expired keys to find during passive clean up duty
+	// before pausing the passive expired keys eviction process
+	JanitorShiftTarget = 25
+
+	// JanitorMaxIterationsPerShift is the maximum number of nodes to traverse before pausing
+	JanitorMaxIterationsPerShift = 1000
+
+	// JanitorMinShiftBackOff is the minimum interval between each iteration of steps
+	// defined by JanitorMaxIterationsPerShift
+	JanitorMinShiftBackOff = time.Millisecond * 50
+
+	// JanitorMaxShiftBackOff is the maximum interval between each iteration of steps
+	// defined by JanitorMaxIterationsPerShift
+	JanitorMaxShiftBackOff = time.Millisecond * 500
+)
+
+// StartJanitor starts the janitor on a different goroutine
+// The janitor's job is to delete expired keys in the background, in other words, it takes care of passive eviction.
+// It can be stopped by calling Cache.StopJanitor.
+// If you do not start the janitor, expired keys will only be deleted when they are accessed through Get, GetByKeys, or
+// GetAll.
+func (cache *Cache) StartJanitor() error {
+	if cache.stopJanitor != nil {
+		return ErrJanitorAlreadyRunning
+	}
+	cache.stopJanitor = make(chan bool)
+	go func() {
+		// rather than starting from the tail on every run, we can try to start from the last next entry
+		var lastTraversedNode *Entry
+		totalNumberOfExpiredKeysInPreviousRunFromTailToHead := 0
+		backOff := JanitorMinShiftBackOff
+		for {
+			select {
+			case <-time.After(backOff):
+				// Passive clean up duty
+				cache.mutex.Lock()
+				if cache.tail != nil {
+					start := time.Now()
+					steps := 0
+					expiredEntriesFound := 0
+					current := cache.tail
+					if lastTraversedNode != nil {
+						// Make sure the lastTraversedNode is still in the cache, otherwise we might be traversing nodes that were already deleted.
+						// Furthermore, we need to make sure that the entry from the cache has the same pointer as the lastTraversedNode
+						// to verify that there isn't just a new cache entry with the same key (i.e. in case lastTraversedNode got evicted)
+						if entryFromCache, isInCache := cache.get(lastTraversedNode.Key); isInCache && entryFromCache == lastTraversedNode {
+							current = lastTraversedNode
+						}
+					}
+					if current == cache.tail {
+						if Debug {
+							log.Printf("There are currently %d entries in the cache. The last walk resulted in finding %d expired keys", len(cache.entries), totalNumberOfExpiredKeysInPreviousRunFromTailToHead)
+						}
+						totalNumberOfExpiredKeysInPreviousRunFromTailToHead = 0
+					}
+					for current != nil {
+						var next *Entry
+						steps++
+						if current.Expired() {
+							expiredEntriesFound++
+							// Because delete will remove the next reference from the entry, we need to store the
+							// next reference before we delete it
+							next = current.next
+							cache.delete(current.Key)
+							cache.stats.ExpiredKeys++
+						}
+						if current == cache.head {
+							lastTraversedNode = nil
+							break
+						}
+						// Travel to the current node's next node only if no specific next node has been specified
+						if next != nil {
+							current = next
+						} else {
+							current = current.next
+						}
+						lastTraversedNode = current
+						if steps == JanitorMaxIterationsPerShift || expiredEntriesFound >= JanitorShiftTarget {
+							if expiredEntriesFound > 0 {
+								backOff = JanitorMinShiftBackOff
+							} else {
+								if backOff*2 <= JanitorMaxShiftBackOff {
+									backOff *= 2
+								} else {
+									backOff = JanitorMaxShiftBackOff
+								}
+							}
+							break
+						}
+					}
+					if Debug {
+						log.Printf("traversed %d nodes and found %d expired entries in %s before stopping\n", steps, expiredEntriesFound, time.Since(start))
+					}
+					totalNumberOfExpiredKeysInPreviousRunFromTailToHead += expiredEntriesFound
+				} else {
+					if backOff*2 < JanitorMaxShiftBackOff {
+						backOff *= 2
+					} else {
+						backOff = JanitorMaxShiftBackOff
+					}
+				}
+				cache.mutex.Unlock()
+			case <-cache.stopJanitor:
+				cache.stopJanitor <- true
+				return
+			}
+		}
+	}()
+	//if Debug {
+	//	go func() {
+	//		var m runtime.MemStats
+	//		for {
+	//			runtime.ReadMemStats(&m)
+	//			log.Printf("Alloc=%vMB; HeapReleased=%vMB; Sys=%vMB; HeapInUse=%vMB; HeapObjects=%v; HeapObjectsFreed=%v; GC=%v; cache.memoryUsage=%vMB; cacheSize=%d\n", m.Alloc/1024/1024, m.HeapReleased/1024/1024, m.Sys/1024/1024, m.HeapInuse/1024/1024, m.HeapObjects, m.Frees, m.NumGC, cache.memoryUsage/1024/1024, cache.Count())
+	//			time.Sleep(3 * time.Second)
+	//		}
+	//	}()
+	//}
+	return nil
+}
+
+// StopJanitor stops the janitor
+func (cache *Cache) StopJanitor() {
+	if cache.stopJanitor != nil {
+		// Tell the janitor to stop, and then wait for the janitor to reply on the same channel that it's stopping
+		// This may seem a bit odd, but this allows us to avoid a data race condition in which setting cache.stopJanitor
+		// to nil
+		cache.stopJanitor <- true
+		<-cache.stopJanitor
+		cache.stopJanitor = nil
+	}
+}

vendor/github.com/TwinProduction/gocache/pattern.go

@@ -0,0 +1,12 @@
+package gocache
+
+import "path/filepath"
+
+// MatchPattern checks whether a string matches a pattern
+func MatchPattern(pattern, s string) bool {
+	if pattern == "*" {
+		return true
+	}
+	matched, _ := filepath.Match(pattern, s)
+	return matched
+}

vendor/github.com/TwinProduction/gocache/persistence.go

@@ -0,0 +1,148 @@
+package gocache
+
+import (
+	"bytes"
+	"encoding/gob"
+	"log"
+	"os"
+	"sort"
+	"time"
+
+	bolt "go.etcd.io/bbolt"
+)
+
+// SaveToFile stores the content of the cache to a file so that it can be read using
+// the ReadFromFile function
+func (cache *Cache) SaveToFile(path string) error {
+	db, err := bolt.Open(path, os.ModePerm, nil)
+	if err != nil {
+		return err
+	}
+	start := time.Now()
+	cache.mutex.RLock()
+	bulkEntries := make([]*Entry, len(cache.entries))
+	i := 0
+	for _, v := range cache.entries {
+		bulkEntries[i] = v
+		i++
+	}
+	cache.mutex.RUnlock()
+	if Debug {
+		log.Printf("unlocked after %s", time.Since(start))
+	}
+	err = db.Update(func(tx *bolt.Tx) error {
+		_ = tx.DeleteBucket([]byte("entries"))
+		bucket, err := tx.CreateBucket([]byte("entries"))
+		if err != nil {
+			return err
+		}
+		for _, bulkEntry := range bulkEntries {
+			buffer := bytes.Buffer{}
+			err = gob.NewEncoder(&buffer).Encode(bulkEntry)
+			if err != nil {
+				// Failed to encode the value, so we'll skip it.
+				// This is likely due to the fact that the custom struct wasn't registered using gob.Register(...)
+				// See [Persistence - Limitations](https://github.com/TwinProduction/gocache#limitations)
+				continue
+			}
+			bucket.Put([]byte(bulkEntry.Key), buffer.Bytes())
+		}
+		return nil
+	})
+	if err != nil {
+		return err
+	}
+	return db.Close()
+}
+
+// ReadFromFile populates the cache using a file created using cache.SaveToFile(path)
+//
+// Note that if the number of entries retrieved from the file exceed the configured maxSize,
+// the extra entries will be automatically evicted according to the EvictionPolicy configured.
+// This function returns the number of entries evicted, and because this function only reads
+// from a file and does not modify it, you can safely retry this function after configuring
+// the cache with the appropriate maxSize, should you desire to.
+func (cache *Cache) ReadFromFile(path string) (int, error) {
+	db, err := bolt.Open(path, os.ModePerm, nil)
+	if err != nil {
+		return 0, err
+	}
+	defer db.Close()
+	cache.mutex.Lock()
+	defer cache.mutex.Unlock()
+	err = db.View(func(tx *bolt.Tx) error {
+		bucket := tx.Bucket([]byte("entries"))
+		// If the bucket doesn't exist, there's nothing to read, so we'll return right now
+		if bucket == nil {
+			return nil
+		}
+		err = bucket.ForEach(func(k, v []byte) error {
+			buffer := new(bytes.Buffer)
+			decoder := gob.NewDecoder(buffer)
+			entry := Entry{}
+			buffer.Write(v)
+			err := decoder.Decode(&entry)
+			if err != nil {
+				// Failed to decode the value, so we'll skip it.
+				// This is likely due to the fact that the custom struct wasn't registered using gob.Register(...)
+				// See [Persistence - Limitations](https://github.com/TwinProduction/gocache#limitations)
+				return err
+			}
+			cache.entries[string(k)] = &entry
+			buffer.Reset()
+			return nil
+		})
+		return err
+	})
+	if err != nil {
+		return 0, err
+	}
+	// Because pointers don't get stored in the file, we need to relink everything from head to tail
+	var entries []*Entry
+	for _, v := range cache.entries {
+		entries = append(entries, v)
+	}
+	// Sort the slice of entries from oldest to newest
+	sort.Slice(entries, func(i, j int) bool {
+		return entries[i].RelevantTimestamp.Before(entries[j].RelevantTimestamp)
+	})
+	// Relink the nodes from tail to head
+	var previous *Entry
+	for i := range entries {
+		current := entries[i]
+		if previous == nil {
+			cache.tail = current
+			cache.head = current
+		} else {
+			previous.next = current
+			current.previous = previous
+			cache.head = current
+		}
+		previous = entries[i]
+		if cache.maxMemoryUsage != NoMaxMemoryUsage {
+			cache.memoryUsage += current.SizeInBytes()
+		}
+	}
+	// If the cache doesn't have a maxSize/maxMemoryUsage, then there's no point checking if we need to evict
+	// an entry, so we'll just return now
+	if cache.maxSize == NoMaxSize && cache.maxMemoryUsage == NoMaxMemoryUsage {
+		return 0, nil
+	}
+	// Evict what needs to be evicted
+	numberOfEvictions := 0
+	// If there's a maxSize and the cache has more entries than the maxSize, evict
+	if cache.maxSize != NoMaxSize && len(cache.entries) > cache.maxSize {
+		for len(cache.entries) > cache.maxSize {
+			numberOfEvictions++
+			cache.evict()
+		}
+	}
+	// If there's a maxMemoryUsage and the memoryUsage is above the maxMemoryUsage, evict
+	if cache.maxMemoryUsage != NoMaxMemoryUsage && cache.memoryUsage > cache.maxMemoryUsage {
+		for cache.memoryUsage > cache.maxMemoryUsage && len(cache.entries) > 0 {
+			numberOfEvictions++
+			cache.evict()
+		}
+	}
+	return numberOfEvictions, nil
+}

vendor/github.com/TwinProduction/gocache/policy.go

@@ -0,0 +1,32 @@
+package gocache
+
+type EvictionPolicy string
+
+var (
+	// LeastRecentlyUsed is an eviction policy that causes the most recently accessed cache entry to be moved to the
+	// head of the cache. Effectively, this causes the cache entries that have not been accessed for some time to
+	// gradually move closer and closer to the tail, and since the tail is the entry that gets deleted when an eviction
+	// is required, it allows less used cache entries to be evicted while keeping recently accessed entries at or close
+	// to the head.
+	//
+	// For instance, creating a Cache with a Cache.MaxSize of 3 and creating the entries 1, 2 and 3 in that order would
+	// put 3 at the head and 1 at the tail:
+	//     3 (head) -> 2 -> 1 (tail)
+	// If the cache entry 1 was then accessed, 1 would become the head and 2 the tail:
+	//     1 (head) -> 3 -> 2 (tail)
+	// If a cache entry 4 was then created, because the Cache.MaxSize is 3, the tail (2) would then be evicted:
+	//     4 (head) -> 1 -> 3 (tail)
+	LeastRecentlyUsed EvictionPolicy = "LeastRecentlyUsed"
+
+	// FirstInFirstOut is an eviction policy that causes cache entries to be evicted in the same order that they are
+	// created.
+	//
+	// For instance, creating a Cache with a Cache.MaxSize of 3 and creating the entries 1, 2 and 3 in that order would
+	// put 3 at the head and 1 at the tail:
+	//     3 (head) -> 2 -> 1 (tail)
+	// If the cache entry 1 was then accessed, unlike with LeastRecentlyUsed, nothing would change:
+	//     3 (head) -> 2 -> 1 (tail)
+	// If a cache entry 4 was then created, because the Cache.MaxSize is 3, the tail (1) would then be evicted:
+	//     4 (head) -> 3 -> 2 (tail)
+	FirstInFirstOut EvictionPolicy = "FirstInFirstOut"
+)

vendor/github.com/TwinProduction/gocache/statistics.go

@@ -0,0 +1,15 @@
+package gocache
+
+type Statistics struct {
+	// EvictedKeys is the number of keys that were evicted
+	EvictedKeys uint64
+
+	// ExpiredKeys is the number of keys that were automatically deleted as a result of expiring
+	ExpiredKeys uint64
+
+	// Hits is the number of cache hits
+	Hits uint64
+
+	// Misses is the number of cache misses
+	Misses uint64
+}

vendor/github.com/TwinProduction/health/.gitattributes

@@ -0,0 +1 @@
+* text=lf

vendor/github.com/TwinProduction/health/.gitignore

@@ -0,0 +1,2 @@
+.idea
+*.iml

vendor/github.com/TwinProduction/health/README.md

@@ -0,0 +1,72 @@
+# health
+
+![build](https://github.com/TwinProduction/health/workflows/build/badge.svg?branch=master) 
+[![Go Report Card](https://goreportcard.com/badge/github.com/TwinProduction/health)](https://goreportcard.com/report/github.com/TwinProduction/health)
+[![codecov](https://codecov.io/gh/TwinProduction/health/branch/master/graph/badge.svg)](https://codecov.io/gh/TwinProduction/health)
+[![Go version](https://img.shields.io/github/go-mod/go-version/TwinProduction/health.svg)](https://github.com/TwinProduction/health)
+[![Go Reference](https://pkg.go.dev/badge/github.com/TwinProduction/health.svg)](https://pkg.go.dev/github.com/TwinProduction/health)
+
+Health is a library used for creating a very simple health endpoint.
+
+While implementing a health endpoint is very simple, I've grown tired of implementing 
+it over and over again.
+
+## Installation
+
+```
+go get -u github.com/TwinProduction/health
+```
+
+
+## Usage
+
+To retrieve the handler, you must use `health.Handler()` and are expected to pass it to the router like so:
+```go
+router := http.NewServeMux()
+router.Handle("/health", health.Handler())
+server := &http.Server{
+	Addr:    ":8080",
+	Handler: router,
+}
+```
+
+By default, the handler will return `UP` when the status is down, and `DOWN` when the status is down.
+If you prefer using JSON, however, you may initialize the health handler like so:
+```go
+router.Handle("/health", health.Handler().WithJSON(true))
+```
+The above will cause the response body to become `{"status":"UP"}` and `{"status":"DOWN"}` for both status respectively.
+
+To change the health of the application, you can use `health.SetStatus(<status>)` where `<status>` is one `health.Up`
+or `health.Down`:
+
+```go
+health.SetStatus(health.Up)
+health.SetStatus(health.Down)
+```
+
+### Complete example
+
+```go
+package main
+
+import (
+	"net/http"
+	"time"
+
+	"github.com/TwinProduction/health"
+)
+
+func main() {
+	router := http.NewServeMux()
+	router.Handle("/health", health.Handler())
+	server := &http.Server{
+		Addr:         "0.0.0.0:8080",
+		Handler:      router,
+		ReadTimeout:  15 * time.Second,
+		WriteTimeout: 15 * time.Second,
+		IdleTimeout:  15 * time.Second,
+	}
+	server.ListenAndServe()
+}
+```

vendor/github.com/TwinProduction/health/go.mod

@@ -0,0 +1,3 @@
+module github.com/TwinProduction/health
+
+go 1.15

vendor/github.com/TwinProduction/health/health.go

@@ -0,0 +1,51 @@
+package health
+
+import "net/http"
+
+var (
+	handler = &healthHandler{
+		useJSON: false,
+		status:  Up,
+	}
+)
+
+type healthHandler struct {
+	useJSON bool
+	status  Status
+}
+
+// WithJSON configures whether the handler should output a response in JSON or in raw text
+//
+// Defaults to false
+func (h *healthHandler) WithJSON(v bool) *healthHandler {
+	h.useJSON = v
+	return h
+}
+
+func (h healthHandler) ServeHTTP(writer http.ResponseWriter, request *http.Request) {
+	var status int
+	var body []byte
+	if h.status == Up {
+		status = http.StatusOK
+	} else {
+		status = http.StatusInternalServerError
+	}
+	if h.useJSON {
+		writer.Header().Set("Content-Type", "application/json")
+		body = []byte(`{"status":"` + h.status + `"}`)
+	} else {
+		body = []byte(h.status)
+	}
+	writer.WriteHeader(status)
+	_, _ = writer.Write(body)
+}
+
+// Handler retrieves the health handler
+func Handler() *healthHandler {
+	return handler
+}
+
+// SetStatus sets the status to be reflected by the health handler
+func SetStatus(status Status) {
+	handler.status = status
+}

vendor/github.com/TwinProduction/health/status.go

@@ -0,0 +1,8 @@
+package health
+
+type Status string
+
+var (
+	Down Status = "DOWN"
+	Up   Status = "UP"
+)

vendor/github.com/gorilla/mux/AUTHORS

@@ -0,0 +1,8 @@
+# This is the official list of gorilla/mux authors for copyright purposes.
+#
+# Please keep the list sorted.
+
+Google LLC (https://opensource.google.com/)
+Kamil Kisielk <kamil@kamilkisiel.net>
+Matt Silverlock <matt@eatsleeprepeat.net>
+Rodrigo Moraes (https://github.com/moraes)

vendor/github.com/gorilla/mux/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2012-2018 The Gorilla Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+	 * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+	 * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+	 * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

vendor/github.com/gorilla/mux/README.md

@@ -0,0 +1,805 @@
+# gorilla/mux
+
+[![GoDoc](https://godoc.org/github.com/gorilla/mux?status.svg)](https://godoc.org/github.com/gorilla/mux)
+[![CircleCI](https://circleci.com/gh/gorilla/mux.svg?style=svg)](https://circleci.com/gh/gorilla/mux)
+[![Sourcegraph](https://sourcegraph.com/github.com/gorilla/mux/-/badge.svg)](https://sourcegraph.com/github.com/gorilla/mux?badge)
+
+![Gorilla Logo](https://cloud-cdn.questionable.services/gorilla-icon-64.png)
+
+https://www.gorillatoolkit.org/pkg/mux
+
+Package `gorilla/mux` implements a request router and dispatcher for matching incoming requests to
+their respective handler.
+
+The name mux stands for "HTTP request multiplexer". Like the standard `http.ServeMux`, `mux.Router` matches incoming requests against a list of registered routes and calls a handler for the route that matches the URL or other conditions. The main features are:
+
+* It implements the `http.Handler` interface so it is compatible with the standard `http.ServeMux`.
+* Requests can be matched based on URL host, path, path prefix, schemes, header and query values, HTTP methods or using custom matchers.
+* URL hosts, paths and query values can have variables with an optional regular expression.
+* Registered URLs can be built, or "reversed", which helps maintaining references to resources.
+* Routes can be used as subrouters: nested routes are only tested if the parent route matches. This is useful to define groups of routes that share common conditions like a host, a path prefix or other repeated attributes. As a bonus, this optimizes request matching.
+
+---
+
+* [Install](#install)
+* [Examples](#examples)
+* [Matching Routes](#matching-routes)
+* [Static Files](#static-files)
+* [Serving Single Page Applications](#serving-single-page-applications) (e.g. React, Vue, Ember.js, etc.)
+* [Registered URLs](#registered-urls)
+* [Walking Routes](#walking-routes)
+* [Graceful Shutdown](#graceful-shutdown)
+* [Middleware](#middleware)
+* [Handling CORS Requests](#handling-cors-requests)
+* [Testing Handlers](#testing-handlers)
+* [Full Example](#full-example)
+
+---
+
+## Install
+
+With a [correctly configured](https://golang.org/doc/install#testing) Go toolchain:
+
+```sh
+go get -u github.com/gorilla/mux
+```
+
+## Examples
+
+Let's start registering a couple of URL paths and handlers:
+
+```go
+func main() {
+    r := mux.NewRouter()
+    r.HandleFunc("/", HomeHandler)
+    r.HandleFunc("/products", ProductsHandler)
+    r.HandleFunc("/articles", ArticlesHandler)
+    http.Handle("/", r)
+}
+```
+
+Here we register three routes mapping URL paths to handlers. This is equivalent to how `http.HandleFunc()` works: if an incoming request URL matches one of the paths, the corresponding handler is called passing (`http.ResponseWriter`, `*http.Request`) as parameters.
+
+Paths can have variables. They are defined using the format `{name}` or `{name:pattern}`. If a regular expression pattern is not defined, the matched variable will be anything until the next slash. For example:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/products/{key}", ProductHandler)
+r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
+r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+```
+
+The names are used to create a map of route variables which can be retrieved calling `mux.Vars()`:
+
+```go
+func ArticlesCategoryHandler(w http.ResponseWriter, r *http.Request) {
+    vars := mux.Vars(r)
+    w.WriteHeader(http.StatusOK)
+    fmt.Fprintf(w, "Category: %v\n", vars["category"])
+}
+```
+
+And this is all you need to know about the basic usage. More advanced options are explained below.
+
+### Matching Routes
+
+Routes can also be restricted to a domain or subdomain. Just define a host pattern to be matched. They can also have variables:
+
+```go
+r := mux.NewRouter()
+// Only matches if domain is "www.example.com".
+r.Host("www.example.com")
+// Matches a dynamic subdomain.
+r.Host("{subdomain:[a-z]+}.example.com")
+```
+
+There are several other matchers that can be added. To match path prefixes:
+
+```go
+r.PathPrefix("/products/")
+```
+
+...or HTTP methods:
+
+```go
+r.Methods("GET", "POST")
+```
+
+...or URL schemes:
+
+```go
+r.Schemes("https")
+```
+
+...or header values:
+
+```go
+r.Headers("X-Requested-With", "XMLHttpRequest")
+```
+
+...or query values:
+
+```go
+r.Queries("key", "value")
+```
+
+...or to use a custom matcher function:
+
+```go
+r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool {
+    return r.ProtoMajor == 0
+})
+```
+
+...and finally, it is possible to combine several matchers in a single route:
+
+```go
+r.HandleFunc("/products", ProductsHandler).
+  Host("www.example.com").
+  Methods("GET").
+  Schemes("http")
+```
+
+Routes are tested in the order they were added to the router. If two routes match, the first one wins:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/specific", specificHandler)
+r.PathPrefix("/").Handler(catchAllHandler)
+```
+
+Setting the same matching conditions again and again can be boring, so we have a way to group several routes that share the same requirements. We call it "subrouting".
+
+For example, let's say we have several URLs that should only match when the host is `www.example.com`. Create a route for that host and get a "subrouter" from it:
+
+```go
+r := mux.NewRouter()
+s := r.Host("www.example.com").Subrouter()
+```
+
+Then register routes in the subrouter:
+
+```go
+s.HandleFunc("/products/", ProductsHandler)
+s.HandleFunc("/products/{key}", ProductHandler)
+s.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+```
+
+The three URL paths we registered above will only be tested if the domain is `www.example.com`, because the subrouter is tested first. This is not only convenient, but also optimizes request matching. You can create subrouters combining any attribute matchers accepted by a route.
+
+Subrouters can be used to create domain or path "namespaces": you define subrouters in a central place and then parts of the app can register its paths relatively to a given subrouter.
+
+There's one more thing about subroutes. When a subrouter has a path prefix, the inner routes use it as base for their paths:
+
+```go
+r := mux.NewRouter()
+s := r.PathPrefix("/products").Subrouter()
+// "/products/"
+s.HandleFunc("/", ProductsHandler)
+// "/products/{key}/"
+s.HandleFunc("/{key}/", ProductHandler)
+// "/products/{key}/details"
+s.HandleFunc("/{key}/details", ProductDetailsHandler)
+```
+
+
+### Static Files
+
+Note that the path provided to `PathPrefix()` represents a "wildcard": calling
+`PathPrefix("/static/").Handler(...)` means that the handler will be passed any
+request that matches "/static/\*". This makes it easy to serve static files with mux:
+
+```go
+func main() {
+    var dir string
+
+    flag.StringVar(&dir, "dir", ".", "the directory to serve files from. Defaults to the current dir")
+    flag.Parse()
+    r := mux.NewRouter()
+
+    // This will serve files under http://localhost:8000/static/<filename>
+    r.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir))))
+
+    srv := &http.Server{
+        Handler:      r,
+        Addr:         "127.0.0.1:8000",
+        // Good practice: enforce timeouts for servers you create!
+        WriteTimeout: 15 * time.Second,
+        ReadTimeout:  15 * time.Second,
+    }
+
+    log.Fatal(srv.ListenAndServe())
+}
+```
+
+### Serving Single Page Applications
+
+Most of the time it makes sense to serve your SPA on a separate web server from your API,
+but sometimes it's desirable to serve them both from one place. It's possible to write a simple
+handler for serving your SPA (for use with React Router's [BrowserRouter](https://reacttraining.com/react-router/web/api/BrowserRouter) for example), and leverage
+mux's powerful routing for your API endpoints.
+
+```go
+package main
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/gorilla/mux"
+)
+
+// spaHandler implements the http.Handler interface, so we can use it
+// to respond to HTTP requests. The path to the static directory and
+// path to the index file within that static directory are used to
+// serve the SPA in the given static directory.
+type spaHandler struct {
+	staticPath string
+	indexPath  string
+}
+
+// ServeHTTP inspects the URL path to locate a file within the static dir
+// on the SPA handler. If a file is found, it will be served. If not, the
+// file located at the index path on the SPA handler will be served. This
+// is suitable behavior for serving an SPA (single page application).
+func (h spaHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+    // get the absolute path to prevent directory traversal
+	path, err := filepath.Abs(r.URL.Path)
+	if err != nil {
+        // if we failed to get the absolute path respond with a 400 bad request
+        // and stop
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+    // prepend the path with the path to the static directory
+	path = filepath.Join(h.staticPath, path)
+
+    // check whether a file exists at the given path
+	_, err = os.Stat(path)
+	if os.IsNotExist(err) {
+		// file does not exist, serve index.html
+		http.ServeFile(w, r, filepath.Join(h.staticPath, h.indexPath))
+		return
+	} else if err != nil {
+        // if we got an error (that wasn't that the file doesn't exist) stating the
+        // file, return a 500 internal server error and stop
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+
+    // otherwise, use http.FileServer to serve the static dir
+	http.FileServer(http.Dir(h.staticPath)).ServeHTTP(w, r)
+}
+
+func main() {
+	router := mux.NewRouter()
+
+	router.HandleFunc("/api/health", func(w http.ResponseWriter, r *http.Request) {
+		// an example API handler
+		json.NewEncoder(w).Encode(map[string]bool{"ok": true})
+	})
+
+	spa := spaHandler{staticPath: "build", indexPath: "index.html"}
+	router.PathPrefix("/").Handler(spa)
+
+	srv := &http.Server{
+		Handler: router,
+		Addr:    "127.0.0.1:8000",
+		// Good practice: enforce timeouts for servers you create!
+		WriteTimeout: 15 * time.Second,
+		ReadTimeout:  15 * time.Second,
+	}
+
+	log.Fatal(srv.ListenAndServe())
+}
+```
+
+### Registered URLs
+
+Now let's see how to build registered URLs.
+
+Routes can be named. All routes that define a name can have their URLs built, or "reversed". We define a name calling `Name()` on a route. For example:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+  Name("article")
+```
+
+To build a URL, get the route and call the `URL()` method, passing a sequence of key/value pairs for the route variables. For the previous route, we would do:
+
+```go
+url, err := r.Get("article").URL("category", "technology", "id", "42")
+```
+
+...and the result will be a `url.URL` with the following path:
+
+```
+"/articles/technology/42"
+```
+
+This also works for host and query value variables:
+
+```go
+r := mux.NewRouter()
+r.Host("{subdomain}.example.com").
+  Path("/articles/{category}/{id:[0-9]+}").
+  Queries("filter", "{filter}").
+  HandlerFunc(ArticleHandler).
+  Name("article")
+
+// url.String() will be "http://news.example.com/articles/technology/42?filter=gorilla"
+url, err := r.Get("article").URL("subdomain", "news",
+                                 "category", "technology",
+                                 "id", "42",
+                                 "filter", "gorilla")
+```
+
+All variables defined in the route are required, and their values must conform to the corresponding patterns. These requirements guarantee that a generated URL will always match a registered route -- the only exception is for explicitly defined "build-only" routes which never match.
+
+Regex support also exists for matching Headers within a route. For example, we could do:
+
+```go
+r.HeadersRegexp("Content-Type", "application/(text|json)")
+```
+
+...and the route will match both requests with a Content-Type of `application/json` as well as `application/text`
+
+There's also a way to build only the URL host or path for a route: use the methods `URLHost()` or `URLPath()` instead. For the previous route, we would do:
+
+```go
+// "http://news.example.com/"
+host, err := r.Get("article").URLHost("subdomain", "news")
+
+// "/articles/technology/42"
+path, err := r.Get("article").URLPath("category", "technology", "id", "42")
+```
+
+And if you use subrouters, host and path defined separately can be built as well:
+
+```go
+r := mux.NewRouter()
+s := r.Host("{subdomain}.example.com").Subrouter()
+s.Path("/articles/{category}/{id:[0-9]+}").
+  HandlerFunc(ArticleHandler).
+  Name("article")
+
+// "http://news.example.com/articles/technology/42"
+url, err := r.Get("article").URL("subdomain", "news",
+                                 "category", "technology",
+                                 "id", "42")
+```
+
+### Walking Routes
+
+The `Walk` function on `mux.Router` can be used to visit all of the routes that are registered on a router. For example,
+the following prints all of the registered routes:
+
+```go
+package main
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+
+	"github.com/gorilla/mux"
+)
+
+func handler(w http.ResponseWriter, r *http.Request) {
+	return
+}
+
+func main() {
+	r := mux.NewRouter()
+	r.HandleFunc("/", handler)
+	r.HandleFunc("/products", handler).Methods("POST")
+	r.HandleFunc("/articles", handler).Methods("GET")
+	r.HandleFunc("/articles/{id}", handler).Methods("GET", "PUT")
+	r.HandleFunc("/authors", handler).Queries("surname", "{surname}")
+	err := r.Walk(func(route *mux.Route, router *mux.Router, ancestors []*mux.Route) error {
+		pathTemplate, err := route.GetPathTemplate()
+		if err == nil {
+			fmt.Println("ROUTE:", pathTemplate)
+		}
+		pathRegexp, err := route.GetPathRegexp()
+		if err == nil {
+			fmt.Println("Path regexp:", pathRegexp)
+		}
+		queriesTemplates, err := route.GetQueriesTemplates()
+		if err == nil {
+			fmt.Println("Queries templates:", strings.Join(queriesTemplates, ","))
+		}
+		queriesRegexps, err := route.GetQueriesRegexp()
+		if err == nil {
+			fmt.Println("Queries regexps:", strings.Join(queriesRegexps, ","))
+		}
+		methods, err := route.GetMethods()
+		if err == nil {
+			fmt.Println("Methods:", strings.Join(methods, ","))
+		}
+		fmt.Println()
+		return nil
+	})
+
+	if err != nil {
+		fmt.Println(err)
+	}
+
+	http.Handle("/", r)
+}
+```
+
+### Graceful Shutdown
+
+Go 1.8 introduced the ability to [gracefully shutdown](https://golang.org/doc/go1.8#http_shutdown) a `*http.Server`. Here's how to do that alongside `mux`:
+
+```go
+package main
+
+import (
+    "context"
+    "flag"
+    "log"
+    "net/http"
+    "os"
+    "os/signal"
+    "time"
+
+    "github.com/gorilla/mux"
+)
+
+func main() {
+    var wait time.Duration
+    flag.DurationVar(&wait, "graceful-timeout", time.Second * 15, "the duration for which the server gracefully wait for existing connections to finish - e.g. 15s or 1m")
+    flag.Parse()
+
+    r := mux.NewRouter()
+    // Add your routes as needed
+
+    srv := &http.Server{
+        Addr:         "0.0.0.0:8080",
+        // Good practice to set timeouts to avoid Slowloris attacks.
+        WriteTimeout: time.Second * 15,
+        ReadTimeout:  time.Second * 15,
+        IdleTimeout:  time.Second * 60,
+        Handler: r, // Pass our instance of gorilla/mux in.
+    }
+
+    // Run our server in a goroutine so that it doesn't block.
+    go func() {
+        if err := srv.ListenAndServe(); err != nil {
+            log.Println(err)
+        }
+    }()
+
+    c := make(chan os.Signal, 1)
+    // We'll accept graceful shutdowns when quit via SIGINT (Ctrl+C)
+    // SIGKILL, SIGQUIT or SIGTERM (Ctrl+/) will not be caught.
+    signal.Notify(c, os.Interrupt)
+
+    // Block until we receive our signal.
+    <-c
+
+    // Create a deadline to wait for.
+    ctx, cancel := context.WithTimeout(context.Background(), wait)
+    defer cancel()
+    // Doesn't block if no connections, but will otherwise wait
+    // until the timeout deadline.
+    srv.Shutdown(ctx)
+    // Optionally, you could run srv.Shutdown in a goroutine and block on
+    // <-ctx.Done() if your application should wait for other services
+    // to finalize based on context cancellation.
+    log.Println("shutting down")
+    os.Exit(0)
+}
+```
+
+### Middleware
+
+Mux supports the addition of middlewares to a [Router](https://godoc.org/github.com/gorilla/mux#Router), which are executed in the order they are added if a match is found, including its subrouters.
+Middlewares are (typically) small pieces of code which take one request, do something with it, and pass it down to another middleware or the final handler. Some common use cases for middleware are request logging, header manipulation, or `ResponseWriter` hijacking.
+
+Mux middlewares are defined using the de facto standard type:
+
+```go
+type MiddlewareFunc func(http.Handler) http.Handler
+```
+
+Typically, the returned handler is a closure which does something with the http.ResponseWriter and http.Request passed to it, and then calls the handler passed as parameter to the MiddlewareFunc. This takes advantage of closures being able access variables from the context where they are created, while retaining the signature enforced by the receivers.
+
+A very basic middleware which logs the URI of the request being handled could be written as:
+
+```go
+func loggingMiddleware(next http.Handler) http.Handler {
+    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+        // Do stuff here
+        log.Println(r.RequestURI)
+        // Call the next handler, which can be another middleware in the chain, or the final handler.
+        next.ServeHTTP(w, r)
+    })
+}
+```
+
+Middlewares can be added to a router using `Router.Use()`:
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/", handler)
+r.Use(loggingMiddleware)
+```
+
+A more complex authentication middleware, which maps session token to users, could be written as:
+
+```go
+// Define our struct
+type authenticationMiddleware struct {
+	tokenUsers map[string]string
+}
+
+// Initialize it somewhere
+func (amw *authenticationMiddleware) Populate() {
+	amw.tokenUsers["00000000"] = "user0"
+	amw.tokenUsers["aaaaaaaa"] = "userA"
+	amw.tokenUsers["05f717e5"] = "randomUser"
+	amw.tokenUsers["deadbeef"] = "user0"
+}
+
+// Middleware function, which will be called for each request
+func (amw *authenticationMiddleware) Middleware(next http.Handler) http.Handler {
+    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+        token := r.Header.Get("X-Session-Token")
+
+        if user, found := amw.tokenUsers[token]; found {
+        	// We found the token in our map
+        	log.Printf("Authenticated user %s\n", user)
+        	// Pass down the request to the next middleware (or final handler)
+        	next.ServeHTTP(w, r)
+        } else {
+        	// Write an error and stop the handler chain
+        	http.Error(w, "Forbidden", http.StatusForbidden)
+        }
+    })
+}
+```
+
+```go
+r := mux.NewRouter()
+r.HandleFunc("/", handler)
+
+amw := authenticationMiddleware{}
+amw.Populate()
+
+r.Use(amw.Middleware)
+```
+
+Note: The handler chain will be stopped if your middleware doesn't call `next.ServeHTTP()` with the corresponding parameters. This can be used to abort a request if the middleware writer wants to. Middlewares _should_ write to `ResponseWriter` if they _are_ going to terminate the request, and they _should not_ write to `ResponseWriter` if they _are not_ going to terminate it.
+
+### Handling CORS Requests
+
+[CORSMethodMiddleware](https://godoc.org/github.com/gorilla/mux#CORSMethodMiddleware) intends to make it easier to strictly set the `Access-Control-Allow-Methods` response header.
+
+* You will still need to use your own CORS handler to set the other CORS headers such as `Access-Control-Allow-Origin`
+* The middleware will set the `Access-Control-Allow-Methods` header to all the method matchers (e.g. `r.Methods(http.MethodGet, http.MethodPut, http.MethodOptions)` -> `Access-Control-Allow-Methods: GET,PUT,OPTIONS`) on a route
+* If you do not specify any methods, then:
+> _Important_: there must be an `OPTIONS` method matcher for the middleware to set the headers.
+
+Here is an example of using `CORSMethodMiddleware` along with a custom `OPTIONS` handler to set all the required CORS headers:
+
+```go
+package main
+
+import (
+	"net/http"
+	"github.com/gorilla/mux"
+)
+
+func main() {
+    r := mux.NewRouter()
+
+    // IMPORTANT: you must specify an OPTIONS method matcher for the middleware to set CORS headers
+    r.HandleFunc("/foo", fooHandler).Methods(http.MethodGet, http.MethodPut, http.MethodPatch, http.MethodOptions)
+    r.Use(mux.CORSMethodMiddleware(r))
+    
+    http.ListenAndServe(":8080", r)
+}
+
+func fooHandler(w http.ResponseWriter, r *http.Request) {
+    w.Header().Set("Access-Control-Allow-Origin", "*")
+    if r.Method == http.MethodOptions {
+        return
+    }
+
+    w.Write([]byte("foo"))
+}
+```
+
+And an request to `/foo` using something like:
+
+```bash
+curl localhost:8080/foo -v
+```
+
+Would look like:
+
+```bash
+*   Trying ::1...
+* TCP_NODELAY set
+* Connected to localhost (::1) port 8080 (#0)
+> GET /foo HTTP/1.1
+> Host: localhost:8080
+> User-Agent: curl/7.59.0
+> Accept: */*
+> 
+< HTTP/1.1 200 OK
+< Access-Control-Allow-Methods: GET,PUT,PATCH,OPTIONS
+< Access-Control-Allow-Origin: *
+< Date: Fri, 28 Jun 2019 20:13:30 GMT
+< Content-Length: 3
+< Content-Type: text/plain; charset=utf-8
+< 
+* Connection #0 to host localhost left intact
+foo
+```
+
+### Testing Handlers
+
+Testing handlers in a Go web application is straightforward, and _mux_ doesn't complicate this any further. Given two files: `endpoints.go` and `endpoints_test.go`, here's how we'd test an application using _mux_.
+
+First, our simple HTTP handler:
+
+```go
+// endpoints.go
+package main
+
+func HealthCheckHandler(w http.ResponseWriter, r *http.Request) {
+    // A very simple health check.
+    w.Header().Set("Content-Type", "application/json")
+    w.WriteHeader(http.StatusOK)
+
+    // In the future we could report back on the status of our DB, or our cache
+    // (e.g. Redis) by performing a simple PING, and include them in the response.
+    io.WriteString(w, `{"alive": true}`)
+}
+
+func main() {
+    r := mux.NewRouter()
+    r.HandleFunc("/health", HealthCheckHandler)
+
+    log.Fatal(http.ListenAndServe("localhost:8080", r))
+}
+```
+
+Our test code:
+
+```go
+// endpoints_test.go
+package main
+
+import (
+    "net/http"
+    "net/http/httptest"
+    "testing"
+)
+
+func TestHealthCheckHandler(t *testing.T) {
+    // Create a request to pass to our handler. We don't have any query parameters for now, so we'll
+    // pass 'nil' as the third parameter.
+    req, err := http.NewRequest("GET", "/health", nil)
+    if err != nil {
+        t.Fatal(err)
+    }
+
+    // We create a ResponseRecorder (which satisfies http.ResponseWriter) to record the response.
+    rr := httptest.NewRecorder()
+    handler := http.HandlerFunc(HealthCheckHandler)
+
+    // Our handlers satisfy http.Handler, so we can call their ServeHTTP method
+    // directly and pass in our Request and ResponseRecorder.
+    handler.ServeHTTP(rr, req)
+
+    // Check the status code is what we expect.
+    if status := rr.Code; status != http.StatusOK {
+        t.Errorf("handler returned wrong status code: got %v want %v",
+            status, http.StatusOK)
+    }
+
+    // Check the response body is what we expect.
+    expected := `{"alive": true}`
+    if rr.Body.String() != expected {
+        t.Errorf("handler returned unexpected body: got %v want %v",
+            rr.Body.String(), expected)
+    }
+}
+```
+
+In the case that our routes have [variables](#examples), we can pass those in the request. We could write
+[table-driven tests](https://dave.cheney.net/2013/06/09/writing-table-driven-tests-in-go) to test multiple
+possible route variables as needed.
+
+```go
+// endpoints.go
+func main() {
+    r := mux.NewRouter()
+    // A route with a route variable:
+    r.HandleFunc("/metrics/{type}", MetricsHandler)
+
+    log.Fatal(http.ListenAndServe("localhost:8080", r))
+}
+```
+
+Our test file, with a table-driven test of `routeVariables`:
+
+```go
+// endpoints_test.go
+func TestMetricsHandler(t *testing.T) {
+    tt := []struct{
+        routeVariable string
+        shouldPass bool
+    }{
+        {"goroutines", true},
+        {"heap", true},
+        {"counters", true},
+        {"queries", true},
+        {"adhadaeqm3k", false},
+    }
+
+    for _, tc := range tt {
+        path := fmt.Sprintf("/metrics/%s", tc.routeVariable)
+        req, err := http.NewRequest("GET", path, nil)
+        if err != nil {
+            t.Fatal(err)
+        }
+
+        rr := httptest.NewRecorder()
+	
+	// Need to create a router that we can pass the request through so that the vars will be added to the context
+	router := mux.NewRouter()
+        router.HandleFunc("/metrics/{type}", MetricsHandler)
+        router.ServeHTTP(rr, req)
+
+        // In this case, our MetricsHandler returns a non-200 response
+        // for a route variable it doesn't know about.
+        if rr.Code == http.StatusOK && !tc.shouldPass {
+            t.Errorf("handler should have failed on routeVariable %s: got %v want %v",
+                tc.routeVariable, rr.Code, http.StatusOK)
+        }
+    }
+}
+```
+
+## Full Example
+
+Here's a complete, runnable example of a small `mux` based server:
+
+```go
+package main
+
+import (
+    "net/http"
+    "log"
+    "github.com/gorilla/mux"
+)
+
+func YourHandler(w http.ResponseWriter, r *http.Request) {
+    w.Write([]byte("Gorilla!\n"))
+}
+
+func main() {
+    r := mux.NewRouter()
+    // Routes consist of a path and a handler function.
+    r.HandleFunc("/", YourHandler)
+
+    // Bind to a port and pass our router in
+    log.Fatal(http.ListenAndServe(":8000", r))
+}
+```
+
+## License
+
+BSD licensed. See the LICENSE file for details.

vendor/github.com/gorilla/mux/doc.go

@@ -0,0 +1,306 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package mux implements a request router and dispatcher.
+
+The name mux stands for "HTTP request multiplexer". Like the standard
+http.ServeMux, mux.Router matches incoming requests against a list of
+registered routes and calls a handler for the route that matches the URL
+or other conditions. The main features are:
+
+	* Requests can be matched based on URL host, path, path prefix, schemes,
+	  header and query values, HTTP methods or using custom matchers.
+	* URL hosts, paths and query values can have variables with an optional
+	  regular expression.
+	* Registered URLs can be built, or "reversed", which helps maintaining
+	  references to resources.
+	* Routes can be used as subrouters: nested routes are only tested if the
+	  parent route matches. This is useful to define groups of routes that
+	  share common conditions like a host, a path prefix or other repeated
+	  attributes. As a bonus, this optimizes request matching.
+	* It implements the http.Handler interface so it is compatible with the
+	  standard http.ServeMux.
+
+Let's start registering a couple of URL paths and handlers:
+
+	func main() {
+		r := mux.NewRouter()
+		r.HandleFunc("/", HomeHandler)
+		r.HandleFunc("/products", ProductsHandler)
+		r.HandleFunc("/articles", ArticlesHandler)
+		http.Handle("/", r)
+	}
+
+Here we register three routes mapping URL paths to handlers. This is
+equivalent to how http.HandleFunc() works: if an incoming request URL matches
+one of the paths, the corresponding handler is called passing
+(http.ResponseWriter, *http.Request) as parameters.
+
+Paths can have variables. They are defined using the format {name} or
+{name:pattern}. If a regular expression pattern is not defined, the matched
+variable will be anything until the next slash. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/products/{key}", ProductHandler)
+	r.HandleFunc("/articles/{category}/", ArticlesCategoryHandler)
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler)
+
+Groups can be used inside patterns, as long as they are non-capturing (?:re). For example:
+
+	r.HandleFunc("/articles/{category}/{sort:(?:asc|desc|new)}", ArticlesCategoryHandler)
+
+The names are used to create a map of route variables which can be retrieved
+calling mux.Vars():
+
+	vars := mux.Vars(request)
+	category := vars["category"]
+
+Note that if any capturing groups are present, mux will panic() during parsing. To prevent
+this, convert any capturing groups to non-capturing, e.g. change "/{sort:(asc|desc)}" to
+"/{sort:(?:asc|desc)}". This is a change from prior versions which behaved unpredictably
+when capturing groups were present.
+
+And this is all you need to know about the basic usage. More advanced options
+are explained below.
+
+Routes can also be restricted to a domain or subdomain. Just define a host
+pattern to be matched. They can also have variables:
+
+	r := mux.NewRouter()
+	// Only matches if domain is "www.example.com".
+	r.Host("www.example.com")
+	// Matches a dynamic subdomain.
+	r.Host("{subdomain:[a-z]+}.domain.com")
+
+There are several other matchers that can be added. To match path prefixes:
+
+	r.PathPrefix("/products/")
+
+...or HTTP methods:
+
+	r.Methods("GET", "POST")
+
+...or URL schemes:
+
+	r.Schemes("https")
+
+...or header values:
+
+	r.Headers("X-Requested-With", "XMLHttpRequest")
+
+...or query values:
+
+	r.Queries("key", "value")
+
+...or to use a custom matcher function:
+
+	r.MatcherFunc(func(r *http.Request, rm *RouteMatch) bool {
+		return r.ProtoMajor == 0
+	})
+
+...and finally, it is possible to combine several matchers in a single route:
+
+	r.HandleFunc("/products", ProductsHandler).
+	  Host("www.example.com").
+	  Methods("GET").
+	  Schemes("http")
+
+Setting the same matching conditions again and again can be boring, so we have
+a way to group several routes that share the same requirements.
+We call it "subrouting".
+
+For example, let's say we have several URLs that should only match when the
+host is "www.example.com". Create a route for that host and get a "subrouter"
+from it:
+
+	r := mux.NewRouter()
+	s := r.Host("www.example.com").Subrouter()
+
+Then register routes in the subrouter:
+
+	s.HandleFunc("/products/", ProductsHandler)
+	s.HandleFunc("/products/{key}", ProductHandler)
+	s.HandleFunc("/articles/{category}/{id:[0-9]+}"), ArticleHandler)
+
+The three URL paths we registered above will only be tested if the domain is
+"www.example.com", because the subrouter is tested first. This is not
+only convenient, but also optimizes request matching. You can create
+subrouters combining any attribute matchers accepted by a route.
+
+Subrouters can be used to create domain or path "namespaces": you define
+subrouters in a central place and then parts of the app can register its
+paths relatively to a given subrouter.
+
+There's one more thing about subroutes. When a subrouter has a path prefix,
+the inner routes use it as base for their paths:
+
+	r := mux.NewRouter()
+	s := r.PathPrefix("/products").Subrouter()
+	// "/products/"
+	s.HandleFunc("/", ProductsHandler)
+	// "/products/{key}/"
+	s.HandleFunc("/{key}/", ProductHandler)
+	// "/products/{key}/details"
+	s.HandleFunc("/{key}/details", ProductDetailsHandler)
+
+Note that the path provided to PathPrefix() represents a "wildcard": calling
+PathPrefix("/static/").Handler(...) means that the handler will be passed any
+request that matches "/static/*". This makes it easy to serve static files with mux:
+
+	func main() {
+		var dir string
+
+		flag.StringVar(&dir, "dir", ".", "the directory to serve files from. Defaults to the current dir")
+		flag.Parse()
+		r := mux.NewRouter()
+
+		// This will serve files under http://localhost:8000/static/<filename>
+		r.PathPrefix("/static/").Handler(http.StripPrefix("/static/", http.FileServer(http.Dir(dir))))
+
+		srv := &http.Server{
+			Handler:      r,
+			Addr:         "127.0.0.1:8000",
+			// Good practice: enforce timeouts for servers you create!
+			WriteTimeout: 15 * time.Second,
+			ReadTimeout:  15 * time.Second,
+		}
+
+		log.Fatal(srv.ListenAndServe())
+	}
+
+Now let's see how to build registered URLs.
+
+Routes can be named. All routes that define a name can have their URLs built,
+or "reversed". We define a name calling Name() on a route. For example:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/articles/{category}/{id:[0-9]+}", ArticleHandler).
+	  Name("article")
+
+To build a URL, get the route and call the URL() method, passing a sequence of
+key/value pairs for the route variables. For the previous route, we would do:
+
+	url, err := r.Get("article").URL("category", "technology", "id", "42")
+
+...and the result will be a url.URL with the following path:
+
+	"/articles/technology/42"
+
+This also works for host and query value variables:
+
+	r := mux.NewRouter()
+	r.Host("{subdomain}.domain.com").
+	  Path("/articles/{category}/{id:[0-9]+}").
+	  Queries("filter", "{filter}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// url.String() will be "http://news.domain.com/articles/technology/42?filter=gorilla"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42",
+	                                 "filter", "gorilla")
+
+All variables defined in the route are required, and their values must
+conform to the corresponding patterns. These requirements guarantee that a
+generated URL will always match a registered route -- the only exception is
+for explicitly defined "build-only" routes which never match.
+
+Regex support also exists for matching Headers within a route. For example, we could do:
+
+	r.HeadersRegexp("Content-Type", "application/(text|json)")
+
+...and the route will match both requests with a Content-Type of `application/json` as well as
+`application/text`
+
+There's also a way to build only the URL host or path for a route:
+use the methods URLHost() or URLPath() instead. For the previous route,
+we would do:
+
+	// "http://news.domain.com/"
+	host, err := r.Get("article").URLHost("subdomain", "news")
+
+	// "/articles/technology/42"
+	path, err := r.Get("article").URLPath("category", "technology", "id", "42")
+
+And if you use subrouters, host and path defined separately can be built
+as well:
+
+	r := mux.NewRouter()
+	s := r.Host("{subdomain}.domain.com").Subrouter()
+	s.Path("/articles/{category}/{id:[0-9]+}").
+	  HandlerFunc(ArticleHandler).
+	  Name("article")
+
+	// "http://news.domain.com/articles/technology/42"
+	url, err := r.Get("article").URL("subdomain", "news",
+	                                 "category", "technology",
+	                                 "id", "42")
+
+Mux supports the addition of middlewares to a Router, which are executed in the order they are added if a match is found, including its subrouters. Middlewares are (typically) small pieces of code which take one request, do something with it, and pass it down to another middleware or the final handler. Some common use cases for middleware are request logging, header manipulation, or ResponseWriter hijacking.
+
+	type MiddlewareFunc func(http.Handler) http.Handler
+
+Typically, the returned handler is a closure which does something with the http.ResponseWriter and http.Request passed to it, and then calls the handler passed as parameter to the MiddlewareFunc (closures can access variables from the context where they are created).
+
+A very basic middleware which logs the URI of the request being handled could be written as:
+
+	func simpleMw(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			// Do stuff here
+			log.Println(r.RequestURI)
+			// Call the next handler, which can be another middleware in the chain, or the final handler.
+			next.ServeHTTP(w, r)
+		})
+	}
+
+Middlewares can be added to a router using `Router.Use()`:
+
+	r := mux.NewRouter()
+	r.HandleFunc("/", handler)
+	r.Use(simpleMw)
+
+A more complex authentication middleware, which maps session token to users, could be written as:
+
+	// Define our struct
+	type authenticationMiddleware struct {
+		tokenUsers map[string]string
+	}
+
+	// Initialize it somewhere
+	func (amw *authenticationMiddleware) Populate() {
+		amw.tokenUsers["00000000"] = "user0"
+		amw.tokenUsers["aaaaaaaa"] = "userA"
+		amw.tokenUsers["05f717e5"] = "randomUser"
+		amw.tokenUsers["deadbeef"] = "user0"
+	}
+
+	// Middleware function, which will be called for each request
+	func (amw *authenticationMiddleware) Middleware(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			token := r.Header.Get("X-Session-Token")
+
+			if user, found := amw.tokenUsers[token]; found {
+				// We found the token in our map
+				log.Printf("Authenticated user %s\n", user)
+				next.ServeHTTP(w, r)
+			} else {
+				http.Error(w, "Forbidden", http.StatusForbidden)
+			}
+		})
+	}
+
+	r := mux.NewRouter()
+	r.HandleFunc("/", handler)
+
+	amw := authenticationMiddleware{tokenUsers: make(map[string]string)}
+	amw.Populate()
+
+	r.Use(amw.Middleware)
+
+Note: The handler chain will be stopped if your middleware doesn't call `next.ServeHTTP()` with the corresponding parameters. This can be used to abort a request if the middleware writer wants to.
+
+*/
+package mux

vendor/github.com/gorilla/mux/go.mod

@@ -0,0 +1,3 @@
+module github.com/gorilla/mux
+
+go 1.12

vendor/github.com/gorilla/mux/middleware.go

@@ -0,0 +1,74 @@
+package mux
+
+import (
+	"net/http"
+	"strings"
+)
+
+// MiddlewareFunc is a function which receives an http.Handler and returns another http.Handler.
+// Typically, the returned handler is a closure which does something with the http.ResponseWriter and http.Request passed
+// to it, and then calls the handler passed as parameter to the MiddlewareFunc.
+type MiddlewareFunc func(http.Handler) http.Handler
+
+// middleware interface is anything which implements a MiddlewareFunc named Middleware.
+type middleware interface {
+	Middleware(handler http.Handler) http.Handler
+}
+
+// Middleware allows MiddlewareFunc to implement the middleware interface.
+func (mw MiddlewareFunc) Middleware(handler http.Handler) http.Handler {
+	return mw(handler)
+}
+
+// Use appends a MiddlewareFunc to the chain. Middleware can be used to intercept or otherwise modify requests and/or responses, and are executed in the order that they are applied to the Router.
+func (r *Router) Use(mwf ...MiddlewareFunc) {
+	for _, fn := range mwf {
+		r.middlewares = append(r.middlewares, fn)
+	}
+}
+
+// useInterface appends a middleware to the chain. Middleware can be used to intercept or otherwise modify requests and/or responses, and are executed in the order that they are applied to the Router.
+func (r *Router) useInterface(mw middleware) {
+	r.middlewares = append(r.middlewares, mw)
+}
+
+// CORSMethodMiddleware automatically sets the Access-Control-Allow-Methods response header
+// on requests for routes that have an OPTIONS method matcher to all the method matchers on
+// the route. Routes that do not explicitly handle OPTIONS requests will not be processed
+// by the middleware. See examples for usage.
+func CORSMethodMiddleware(r *Router) MiddlewareFunc {
+	return func(next http.Handler) http.Handler {
+		return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+			allMethods, err := getAllMethodsForRoute(r, req)
+			if err == nil {
+				for _, v := range allMethods {
+					if v == http.MethodOptions {
+						w.Header().Set("Access-Control-Allow-Methods", strings.Join(allMethods, ","))
+					}
+				}
+			}
+
+			next.ServeHTTP(w, req)
+		})
+	}
+}
+
+// getAllMethodsForRoute returns all the methods from method matchers matching a given
+// request.
+func getAllMethodsForRoute(r *Router, req *http.Request) ([]string, error) {
+	var allMethods []string
+
+	for _, route := range r.routes {
+		var match RouteMatch
+		if route.Match(req, &match) || match.MatchErr == ErrMethodMismatch {
+			methods, err := route.GetMethods()
+			if err != nil {
+				return nil, err
+			}
+
+			allMethods = append(allMethods, methods...)
+		}
+	}
+
+	return allMethods, nil
+}

vendor/github.com/gorilla/mux/mux.go

@@ -0,0 +1,606 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"path"
+	"regexp"
+)
+
+var (
+	// ErrMethodMismatch is returned when the method in the request does not match
+	// the method defined against the route.
+	ErrMethodMismatch = errors.New("method is not allowed")
+	// ErrNotFound is returned when no route match is found.
+	ErrNotFound = errors.New("no matching route was found")
+)
+
+// NewRouter returns a new router instance.
+func NewRouter() *Router {
+	return &Router{namedRoutes: make(map[string]*Route)}
+}
+
+// Router registers routes to be matched and dispatches a handler.
+//
+// It implements the http.Handler interface, so it can be registered to serve
+// requests:
+//
+//     var router = mux.NewRouter()
+//
+//     func main() {
+//         http.Handle("/", router)
+//     }
+//
+// Or, for Google App Engine, register it in a init() function:
+//
+//     func init() {
+//         http.Handle("/", router)
+//     }
+//
+// This will send all incoming requests to the router.
+type Router struct {
+	// Configurable Handler to be used when no route matches.
+	NotFoundHandler http.Handler
+
+	// Configurable Handler to be used when the request method does not match the route.
+	MethodNotAllowedHandler http.Handler
+
+	// Routes to be matched, in order.
+	routes []*Route
+
+	// Routes by name for URL building.
+	namedRoutes map[string]*Route
+
+	// If true, do not clear the request context after handling the request.
+	//
+	// Deprecated: No effect, since the context is stored on the request itself.
+	KeepContext bool
+
+	// Slice of middlewares to be called after a match is found
+	middlewares []middleware
+
+	// configuration shared with `Route`
+	routeConf
+}
+
+// common route configuration shared between `Router` and `Route`
+type routeConf struct {
+	// If true, "/path/foo%2Fbar/to" will match the path "/path/{var}/to"
+	useEncodedPath bool
+
+	// If true, when the path pattern is "/path/", accessing "/path" will
+	// redirect to the former and vice versa.
+	strictSlash bool
+
+	// If true, when the path pattern is "/path//to", accessing "/path//to"
+	// will not redirect
+	skipClean bool
+
+	// Manager for the variables from host and path.
+	regexp routeRegexpGroup
+
+	// List of matchers.
+	matchers []matcher
+
+	// The scheme used when building URLs.
+	buildScheme string
+
+	buildVarsFunc BuildVarsFunc
+}
+
+// returns an effective deep copy of `routeConf`
+func copyRouteConf(r routeConf) routeConf {
+	c := r
+
+	if r.regexp.path != nil {
+		c.regexp.path = copyRouteRegexp(r.regexp.path)
+	}
+
+	if r.regexp.host != nil {
+		c.regexp.host = copyRouteRegexp(r.regexp.host)
+	}
+
+	c.regexp.queries = make([]*routeRegexp, 0, len(r.regexp.queries))
+	for _, q := range r.regexp.queries {
+		c.regexp.queries = append(c.regexp.queries, copyRouteRegexp(q))
+	}
+
+	c.matchers = make([]matcher, len(r.matchers))
+	copy(c.matchers, r.matchers)
+
+	return c
+}
+
+func copyRouteRegexp(r *routeRegexp) *routeRegexp {
+	c := *r
+	return &c
+}
+
+// Match attempts to match the given request against the router's registered routes.
+//
+// If the request matches a route of this router or one of its subrouters the Route,
+// Handler, and Vars fields of the the match argument are filled and this function
+// returns true.
+//
+// If the request does not match any of this router's or its subrouters' routes
+// then this function returns false. If available, a reason for the match failure
+// will be filled in the match argument's MatchErr field. If the match failure type
+// (eg: not found) has a registered handler, the handler is assigned to the Handler
+// field of the match argument.
+func (r *Router) Match(req *http.Request, match *RouteMatch) bool {
+	for _, route := range r.routes {
+		if route.Match(req, match) {
+			// Build middleware chain if no error was found
+			if match.MatchErr == nil {
+				for i := len(r.middlewares) - 1; i >= 0; i-- {
+					match.Handler = r.middlewares[i].Middleware(match.Handler)
+				}
+			}
+			return true
+		}
+	}
+
+	if match.MatchErr == ErrMethodMismatch {
+		if r.MethodNotAllowedHandler != nil {
+			match.Handler = r.MethodNotAllowedHandler
+			return true
+		}
+
+		return false
+	}
+
+	// Closest match for a router (includes sub-routers)
+	if r.NotFoundHandler != nil {
+		match.Handler = r.NotFoundHandler
+		match.MatchErr = ErrNotFound
+		return true
+	}
+
+	match.MatchErr = ErrNotFound
+	return false
+}
+
+// ServeHTTP dispatches the handler registered in the matched route.
+//
+// When there is a match, the route variables can be retrieved calling
+// mux.Vars(request).
+func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	if !r.skipClean {
+		path := req.URL.Path
+		if r.useEncodedPath {
+			path = req.URL.EscapedPath()
+		}
+		// Clean path to canonical form and redirect.
+		if p := cleanPath(path); p != path {
+
+			// Added 3 lines (Philip Schlump) - It was dropping the query string and #whatever from query.
+			// This matches with fix in go 1.2 r.c. 4 for same problem.  Go Issue:
+			// http://code.google.com/p/go/issues/detail?id=5252
+			url := *req.URL
+			url.Path = p
+			p = url.String()
+
+			w.Header().Set("Location", p)
+			w.WriteHeader(http.StatusMovedPermanently)
+			return
+		}
+	}
+	var match RouteMatch
+	var handler http.Handler
+	if r.Match(req, &match) {
+		handler = match.Handler
+		req = requestWithVars(req, match.Vars)
+		req = requestWithRoute(req, match.Route)
+	}
+
+	if handler == nil && match.MatchErr == ErrMethodMismatch {
+		handler = methodNotAllowedHandler()
+	}
+
+	if handler == nil {
+		handler = http.NotFoundHandler()
+	}
+
+	handler.ServeHTTP(w, req)
+}
+
+// Get returns a route registered with the given name.
+func (r *Router) Get(name string) *Route {
+	return r.namedRoutes[name]
+}
+
+// GetRoute returns a route registered with the given name. This method
+// was renamed to Get() and remains here for backwards compatibility.
+func (r *Router) GetRoute(name string) *Route {
+	return r.namedRoutes[name]
+}
+
+// StrictSlash defines the trailing slash behavior for new routes. The initial
+// value is false.
+//
+// When true, if the route path is "/path/", accessing "/path" will perform a redirect
+// to the former and vice versa. In other words, your application will always
+// see the path as specified in the route.
+//
+// When false, if the route path is "/path", accessing "/path/" will not match
+// this route and vice versa.
+//
+// The re-direct is a HTTP 301 (Moved Permanently). Note that when this is set for
+// routes with a non-idempotent method (e.g. POST, PUT), the subsequent re-directed
+// request will be made as a GET by most clients. Use middleware or client settings
+// to modify this behaviour as needed.
+//
+// Special case: when a route sets a path prefix using the PathPrefix() method,
+// strict slash is ignored for that route because the redirect behavior can't
+// be determined from a prefix alone. However, any subrouters created from that
+// route inherit the original StrictSlash setting.
+func (r *Router) StrictSlash(value bool) *Router {
+	r.strictSlash = value
+	return r
+}
+
+// SkipClean defines the path cleaning behaviour for new routes. The initial
+// value is false. Users should be careful about which routes are not cleaned
+//
+// When true, if the route path is "/path//to", it will remain with the double
+// slash. This is helpful if you have a route like: /fetch/http://xkcd.com/534/
+//
+// When false, the path will be cleaned, so /fetch/http://xkcd.com/534/ will
+// become /fetch/http/xkcd.com/534
+func (r *Router) SkipClean(value bool) *Router {
+	r.skipClean = value
+	return r
+}
+
+// UseEncodedPath tells the router to match the encoded original path
+// to the routes.
+// For eg. "/path/foo%2Fbar/to" will match the path "/path/{var}/to".
+//
+// If not called, the router will match the unencoded path to the routes.
+// For eg. "/path/foo%2Fbar/to" will match the path "/path/foo/bar/to"
+func (r *Router) UseEncodedPath() *Router {
+	r.useEncodedPath = true
+	return r
+}
+
+// ----------------------------------------------------------------------------
+// Route factories
+// ----------------------------------------------------------------------------
+
+// NewRoute registers an empty route.
+func (r *Router) NewRoute() *Route {
+	// initialize a route with a copy of the parent router's configuration
+	route := &Route{routeConf: copyRouteConf(r.routeConf), namedRoutes: r.namedRoutes}
+	r.routes = append(r.routes, route)
+	return route
+}
+
+// Name registers a new route with a name.
+// See Route.Name().
+func (r *Router) Name(name string) *Route {
+	return r.NewRoute().Name(name)
+}
+
+// Handle registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.Handler().
+func (r *Router) Handle(path string, handler http.Handler) *Route {
+	return r.NewRoute().Path(path).Handler(handler)
+}
+
+// HandleFunc registers a new route with a matcher for the URL path.
+// See Route.Path() and Route.HandlerFunc().
+func (r *Router) HandleFunc(path string, f func(http.ResponseWriter,
+	*http.Request)) *Route {
+	return r.NewRoute().Path(path).HandlerFunc(f)
+}
+
+// Headers registers a new route with a matcher for request header values.
+// See Route.Headers().
+func (r *Router) Headers(pairs ...string) *Route {
+	return r.NewRoute().Headers(pairs...)
+}
+
+// Host registers a new route with a matcher for the URL host.
+// See Route.Host().
+func (r *Router) Host(tpl string) *Route {
+	return r.NewRoute().Host(tpl)
+}
+
+// MatcherFunc registers a new route with a custom matcher function.
+// See Route.MatcherFunc().
+func (r *Router) MatcherFunc(f MatcherFunc) *Route {
+	return r.NewRoute().MatcherFunc(f)
+}
+
+// Methods registers a new route with a matcher for HTTP methods.
+// See Route.Methods().
+func (r *Router) Methods(methods ...string) *Route {
+	return r.NewRoute().Methods(methods...)
+}
+
+// Path registers a new route with a matcher for the URL path.
+// See Route.Path().
+func (r *Router) Path(tpl string) *Route {
+	return r.NewRoute().Path(tpl)
+}
+
+// PathPrefix registers a new route with a matcher for the URL path prefix.
+// See Route.PathPrefix().
+func (r *Router) PathPrefix(tpl string) *Route {
+	return r.NewRoute().PathPrefix(tpl)
+}
+
+// Queries registers a new route with a matcher for URL query values.
+// See Route.Queries().
+func (r *Router) Queries(pairs ...string) *Route {
+	return r.NewRoute().Queries(pairs...)
+}
+
+// Schemes registers a new route with a matcher for URL schemes.
+// See Route.Schemes().
+func (r *Router) Schemes(schemes ...string) *Route {
+	return r.NewRoute().Schemes(schemes...)
+}
+
+// BuildVarsFunc registers a new route with a custom function for modifying
+// route variables before building a URL.
+func (r *Router) BuildVarsFunc(f BuildVarsFunc) *Route {
+	return r.NewRoute().BuildVarsFunc(f)
+}
+
+// Walk walks the router and all its sub-routers, calling walkFn for each route
+// in the tree. The routes are walked in the order they were added. Sub-routers
+// are explored depth-first.
+func (r *Router) Walk(walkFn WalkFunc) error {
+	return r.walk(walkFn, []*Route{})
+}
+
+// SkipRouter is used as a return value from WalkFuncs to indicate that the
+// router that walk is about to descend down to should be skipped.
+var SkipRouter = errors.New("skip this router")
+
+// WalkFunc is the type of the function called for each route visited by Walk.
+// At every invocation, it is given the current route, and the current router,
+// and a list of ancestor routes that lead to the current route.
+type WalkFunc func(route *Route, router *Router, ancestors []*Route) error
+
+func (r *Router) walk(walkFn WalkFunc, ancestors []*Route) error {
+	for _, t := range r.routes {
+		err := walkFn(t, r, ancestors)
+		if err == SkipRouter {
+			continue
+		}
+		if err != nil {
+			return err
+		}
+		for _, sr := range t.matchers {
+			if h, ok := sr.(*Router); ok {
+				ancestors = append(ancestors, t)
+				err := h.walk(walkFn, ancestors)
+				if err != nil {
+					return err
+				}
+				ancestors = ancestors[:len(ancestors)-1]
+			}
+		}
+		if h, ok := t.handler.(*Router); ok {
+			ancestors = append(ancestors, t)
+			err := h.walk(walkFn, ancestors)
+			if err != nil {
+				return err
+			}
+			ancestors = ancestors[:len(ancestors)-1]
+		}
+	}
+	return nil
+}
+
+// ----------------------------------------------------------------------------
+// Context
+// ----------------------------------------------------------------------------
+
+// RouteMatch stores information about a matched route.
+type RouteMatch struct {
+	Route   *Route
+	Handler http.Handler
+	Vars    map[string]string
+
+	// MatchErr is set to appropriate matching error
+	// It is set to ErrMethodMismatch if there is a mismatch in
+	// the request method and route method
+	MatchErr error
+}
+
+type contextKey int
+
+const (
+	varsKey contextKey = iota
+	routeKey
+)
+
+// Vars returns the route variables for the current request, if any.
+func Vars(r *http.Request) map[string]string {
+	if rv := r.Context().Value(varsKey); rv != nil {
+		return rv.(map[string]string)
+	}
+	return nil
+}
+
+// CurrentRoute returns the matched route for the current request, if any.
+// This only works when called inside the handler of the matched route
+// because the matched route is stored in the request context which is cleared
+// after the handler returns.
+func CurrentRoute(r *http.Request) *Route {
+	if rv := r.Context().Value(routeKey); rv != nil {
+		return rv.(*Route)
+	}
+	return nil
+}
+
+func requestWithVars(r *http.Request, vars map[string]string) *http.Request {
+	ctx := context.WithValue(r.Context(), varsKey, vars)
+	return r.WithContext(ctx)
+}
+
+func requestWithRoute(r *http.Request, route *Route) *http.Request {
+	ctx := context.WithValue(r.Context(), routeKey, route)
+	return r.WithContext(ctx)
+}
+
+// ----------------------------------------------------------------------------
+// Helpers
+// ----------------------------------------------------------------------------
+
+// cleanPath returns the canonical path for p, eliminating . and .. elements.
+// Borrowed from the net/http package.
+func cleanPath(p string) string {
+	if p == "" {
+		return "/"
+	}
+	if p[0] != '/' {
+		p = "/" + p
+	}
+	np := path.Clean(p)
+	// path.Clean removes trailing slash except for root;
+	// put the trailing slash back if necessary.
+	if p[len(p)-1] == '/' && np != "/" {
+		np += "/"
+	}
+
+	return np
+}
+
+// uniqueVars returns an error if two slices contain duplicated strings.
+func uniqueVars(s1, s2 []string) error {
+	for _, v1 := range s1 {
+		for _, v2 := range s2 {
+			if v1 == v2 {
+				return fmt.Errorf("mux: duplicated route variable %q", v2)
+			}
+		}
+	}
+	return nil
+}
+
+// checkPairs returns the count of strings passed in, and an error if
+// the count is not an even number.
+func checkPairs(pairs ...string) (int, error) {
+	length := len(pairs)
+	if length%2 != 0 {
+		return length, fmt.Errorf(
+			"mux: number of parameters must be multiple of 2, got %v", pairs)
+	}
+	return length, nil
+}
+
+// mapFromPairsToString converts variadic string parameters to a
+// string to string map.
+func mapFromPairsToString(pairs ...string) (map[string]string, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]string, length/2)
+	for i := 0; i < length; i += 2 {
+		m[pairs[i]] = pairs[i+1]
+	}
+	return m, nil
+}
+
+// mapFromPairsToRegex converts variadic string parameters to a
+// string to regex map.
+func mapFromPairsToRegex(pairs ...string) (map[string]*regexp.Regexp, error) {
+	length, err := checkPairs(pairs...)
+	if err != nil {
+		return nil, err
+	}
+	m := make(map[string]*regexp.Regexp, length/2)
+	for i := 0; i < length; i += 2 {
+		regex, err := regexp.Compile(pairs[i+1])
+		if err != nil {
+			return nil, err
+		}
+		m[pairs[i]] = regex
+	}
+	return m, nil
+}
+
+// matchInArray returns true if the given string value is in the array.
+func matchInArray(arr []string, value string) bool {
+	for _, v := range arr {
+		if v == value {
+			return true
+		}
+	}
+	return false
+}
+
+// matchMapWithString returns true if the given key/value pairs exist in a given map.
+func matchMapWithString(toCheck map[string]string, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != "" {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v == value {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// matchMapWithRegex returns true if the given key/value pairs exist in a given map compiled against
+// the given regex
+func matchMapWithRegex(toCheck map[string]*regexp.Regexp, toMatch map[string][]string, canonicalKey bool) bool {
+	for k, v := range toCheck {
+		// Check if key exists.
+		if canonicalKey {
+			k = http.CanonicalHeaderKey(k)
+		}
+		if values := toMatch[k]; values == nil {
+			return false
+		} else if v != nil {
+			// If value was defined as an empty string we only check that the
+			// key exists. Otherwise we also check for equality.
+			valueExists := false
+			for _, value := range values {
+				if v.MatchString(value) {
+					valueExists = true
+					break
+				}
+			}
+			if !valueExists {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+// methodNotAllowed replies to the request with an HTTP status code 405.
+func methodNotAllowed(w http.ResponseWriter, r *http.Request) {
+	w.WriteHeader(http.StatusMethodNotAllowed)
+}
+
+// methodNotAllowedHandler returns a simple request handler
+// that replies to each request with a status code 405.
+func methodNotAllowedHandler() http.Handler { return http.HandlerFunc(methodNotAllowed) }

vendor/github.com/gorilla/mux/regexp.go

@@ -0,0 +1,388 @@
+// Copyright 2012 The Gorilla Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package mux
+
+import (
+	"bytes"
+	"fmt"
+	"net/http"
+	"net/url"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+type routeRegexpOptions struct {
+	strictSlash    bool
+	useEncodedPath bool
+}
+
+type regexpType int
+
+const (
+	regexpTypePath   regexpType = 0
+	regexpTypeHost   regexpType = 1
+	regexpTypePrefix regexpType = 2
+	regexpTypeQuery  regexpType = 3
+)
+
+// newRouteRegexp parses a route template and returns a routeRegexp,
+// used to match a host, a path or a query string.
+//
+// It will extract named variables, assemble a regexp to be matched, create
+// a "reverse" template to build URLs and compile regexps to validate variable
+// values used in URL building.
+//
+// Previously we accepted only Python-like identifiers for variable
+// names ([a-zA-Z_][a-zA-Z0-9_]*), but currently the only restriction is that
+// name and pattern can't be empty, and names can't contain a colon.
+func newRouteRegexp(tpl string, typ regexpType, options routeRegexpOptions) (*routeRegexp, error) {
+	// Check if it is well-formed.
+	idxs, errBraces := braceIndices(tpl)
+	if errBraces != nil {
+		return nil, errBraces
+	}
+	// Backup the original.
+	template := tpl
+	// Now let's parse it.
+	defaultPattern := "[^/]+"
+	if typ == regexpTypeQuery {
+		defaultPattern = ".*"
+	} else if typ == regexpTypeHost {
+		defaultPattern = "[^.]+"
+	}
+	// Only match strict slash if not matching
+	if typ != regexpTypePath {
+		options.strictSlash = false
+	}
+	// Set a flag for strictSlash.
+	endSlash := false
+	if options.strictSlash && strings.HasSuffix(tpl, "/") {
+		tpl = tpl[:len(tpl)-1]
+		endSlash = true
+	}
+	varsN := make([]string, len(idxs)/2)
+	varsR := make([]*regexp.Regexp, len(idxs)/2)
+	pattern := bytes.NewBufferString("")
+	pattern.WriteByte('^')
+	reverse := bytes.NewBufferString("")
+	var end int
+	var err error
+	for i := 0; i < len(idxs); i += 2 {
+		// Set all values we are interested in.
+		raw := tpl[end:idxs[i]]
+		end = idxs[i+1]
+		parts := strings.SplitN(tpl[idxs[i]+1:end-1], ":", 2)
+		name := parts[0]
+		patt := defaultPattern
+		if len(parts) == 2 {
+			patt = parts[1]
+		}
+		// Name or pattern can't be empty.
+		if name == "" || patt == "" {
+			return nil, fmt.Errorf("mux: missing name or pattern in %q",
+				tpl[idxs[i]:end])
+		}
+		// Build the regexp pattern.
+		fmt.Fprintf(pattern, "%s(?P<%s>%s)", regexp.QuoteMeta(raw), varGroupName(i/2), patt)
+
+		// Build the reverse template.
+		fmt.Fprintf(reverse, "%s%%s", raw)
+
+		// Append variable name and compiled pattern.
+		varsN[i/2] = name
+		varsR[i/2], err = regexp.Compile(fmt.Sprintf("^%s$", patt))
+		if err != nil {
+			return nil, err
+		}
+	}
+	// Add the remaining.
+	raw := tpl[end:]
+	pattern.WriteString(regexp.QuoteMeta(raw))
+	if options.strictSlash {
+		pattern.WriteString("[/]?")
+	}
+	if typ == regexpTypeQuery {
+		// Add the default pattern if the query value is empty
+		if queryVal := strings.SplitN(template, "=", 2)[1]; queryVal == "" {
+			pattern.WriteString(defaultPattern)
+		}
+	}
+	if typ != regexpTypePrefix {
+		pattern.WriteByte('$')
+	}
+
+	var wildcardHostPort bool
+	if typ == regexpTypeHost {
+		if !strings.Contains(pattern.String(), ":") {
+			wildcardHostPort = true
+		}
+	}
+	reverse.WriteString(raw)
+	if endSlash {
+		reverse.WriteByte('/')
+	}
+	// Compile full regexp.
+	reg, errCompile := regexp.Compile(pattern.String())
+	if errCompile != nil {
+		return nil, errCompile
+	}
+
+	// Check for capturing groups which used to work in older versions
+	if reg.NumSubexp() != len(idxs)/2 {
+		panic(fmt.Sprintf("route %s contains capture groups in its regexp. ", template) +
+			"Only non-capturing groups are accepted: e.g. (?:pattern) instead of (pattern)")
+	}
+
+	// Done!
+	return &routeRegexp{
+		template:         template,
+		regexpType:       typ,
+		options:          options,
+		regexp:           reg,
+		reverse:          reverse.String(),
+		varsN:            varsN,
+		varsR:            varsR,
+		wildcardHostPort: wildcardHostPort,
+	}, nil
+}
+
+// routeRegexp stores a regexp to match a host or path and information to
+// collect and validate route variables.
+type routeRegexp struct {
+	// The unmodified template.
+	template string
+	// The type of match
+	regexpType regexpType
+	// Options for matching
+	options routeRegexpOptions
+	// Expanded regexp.
+	regexp *regexp.Regexp
+	// Reverse template.
+	reverse string
+	// Variable names.
+	varsN []string
+	// Variable regexps (validators).
+	varsR []*regexp.Regexp
+	// Wildcard host-port (no strict port match in hostname)
+	wildcardHostPort bool
+}
+
+// Match matches the regexp against the URL host or path.
+func (r *routeRegexp) Match(req *http.Request, match *RouteMatch) bool {
+	if r.regexpType == regexpTypeHost {
+		host := getHost(req)
+		if r.wildcardHostPort {
+			// Don't be strict on the port match
+			if i := strings.Index(host, ":"); i != -1 {
+				host = host[:i]
+			}
+		}
+		return r.regexp.MatchString(host)
+	}
+
+	if r.regexpType == regexpTypeQuery {
+		return r.matchQueryString(req)
+	}
+	path := req.URL.Path
+	if r.options.useEncodedPath {
+		path = req.URL.EscapedPath()
+	}
+	return r.regexp.MatchString(path)
+}
+
+// url builds a URL part using the given values.
+func (r *routeRegexp) url(values map[string]string) (string, error) {
+	urlValues := make([]interface{}, len(r.varsN), len(r.varsN))
+	for k, v := range r.varsN {
+		value, ok := values[v]
+		if !ok {
+			return "", fmt.Errorf("mux: missing route variable %q", v)
+		}
+		if r.regexpType == regexpTypeQuery {
+			value = url.QueryEscape(value)
+		}
+		urlValues[k] = value
+	}
+	rv := fmt.Sprintf(r.reverse, urlValues...)
+	if !r.regexp.MatchString(rv) {
+		// The URL is checked against the full regexp, instead of checking
+		// individual variables. This is faster but to provide a good error
+		// message, we check individual regexps if the URL doesn't match.
+		for k, v := range r.varsN {
+			if !r.varsR[k].MatchString(values[v]) {
+				return "", fmt.Errorf(
+					"mux: variable %q doesn't match, expected %q", values[v],
+					r.varsR[k].String())
+			}
+		}
+	}
+	return rv, nil
+}
+
+// getURLQuery returns a single query parameter from a request URL.
+// For a URL with foo=bar&baz=ding, we return only the relevant key
+// value pair for the routeRegexp.
+func (r *routeRegexp) getURLQuery(req *http.Request) string {
+	if r.regexpType != regexpTypeQuery {
+		return ""
+	}
+	templateKey := strings.SplitN(r.template, "=", 2)[0]
+	val, ok := findFirstQueryKey(req.URL.RawQuery, templateKey)
+	if ok {
+		return templateKey + "=" + val
+	}
+	return ""
+}
+
+// findFirstQueryKey returns the same result as (*url.URL).Query()[key][0].
+// If key was not found, empty string and false is returned.
+func findFirstQueryKey(rawQuery, key string) (value string, ok bool) {
+	query := []byte(rawQuery)
+	for len(query) > 0 {
+		foundKey := query
+		if i := bytes.IndexAny(foundKey, "&;"); i >= 0 {
+			foundKey, query = foundKey[:i], foundKey[i+1:]
+		} else {
+			query = query[:0]
+		}
+		if len(foundKey) == 0 {
+			continue
+		}
+		var value []byte
+		if i := bytes.IndexByte(foundKey, '='); i >= 0 {
+			foundKey, value = foundKey[:i], foundKey[i+1:]
+		}
+		if len(foundKey) < len(key) {
+			// Cannot possibly be key.
+			continue
+		}
+		keyString, err := url.QueryUnescape(string(foundKey))
+		if err != nil {
+			continue
+		}
+		if keyString != key {
+			continue
+		}
+		valueString, err := url.QueryUnescape(string(value))
+		if err != nil {
+			continue
+		}
+		return valueString, true
+	}
+	return "", false
+}
+
+func (r *routeRegexp) matchQueryString(req *http.Request) bool {
+	return r.regexp.MatchString(r.getURLQuery(req))
+}
+
+// braceIndices returns the first level curly brace indices from a string.
+// It returns an error in case of unbalanced braces.
+func braceIndices(s string) ([]int, error) {
+	var level, idx int
+	var idxs []int
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '{':
+			if level++; level == 1 {
+				idx = i
+			}
+		case '}':
+			if level--; level == 0 {
+				idxs = append(idxs, idx, i+1)
+			} else if level < 0 {
+				return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+			}
+		}
+	}
+	if level != 0 {
+		return nil, fmt.Errorf("mux: unbalanced braces in %q", s)
+	}
+	return idxs, nil
+}
+
+// varGroupName builds a capturing group name for the indexed variable.
+func varGroupName(idx int) string {
+	return "v" + strconv.Itoa(idx)
+}
+
+// ----------------------------------------------------------------------------
+// routeRegexpGroup
+// ----------------------------------------------------------------------------
+
+// routeRegexpGroup groups the route matchers that carry variables.
+type routeRegexpGroup struct {
+	host    *routeRegexp
+	path    *routeRegexp
+	queries []*routeRegexp
+}
+
+// setMatch extracts the variables from the URL once a route matches.
+func (v routeRegexpGroup) setMatch(req *http.Request, m *RouteMatch, r *Route) {
+	// Store host variables.
+	if v.host != nil {
+		host := getHost(req)
+		if v.host.wildcardHostPort {
+			// Don't be strict on the port match
+			if i := strings.Index(host, ":"); i != -1 {
+				host = host[:i]
+			}
+		}
+		matches := v.host.regexp.FindStringSubmatchIndex(host)
+		if len(matches) > 0 {
+			extractVars(host, matches, v.host.varsN, m.Vars)
+		}
+	}
+	path := req.URL.Path
+	if r.useEncodedPath {
+		path = req.URL.EscapedPath()
+	}
+	// Store path variables.
+	if v.path != nil {
+		matches := v.path.regexp.FindStringSubmatchIndex(path)
+		if len(matches) > 0 {
+			extractVars(path, matches, v.path.varsN, m.Vars)
+			// Check if we should redirect.
+			if v.path.options.strictSlash {
+				p1 := strings.HasSuffix(path, "/")
+				p2 := strings.HasSuffix(v.path.template, "/")
+				if p1 != p2 {
+					u, _ := url.Parse(req.URL.String())
+					if p1 {
+						u.Path = u.Path[:len(u.Path)-1]
+					} else {
+						u.Path += "/"
+					}
+					m.Handler = http.RedirectHandler(u.String(), http.StatusMovedPermanently)
+				}
+			}
+		}
+	}
+	// Store query string variables.
+	for _, q := range v.queries {
+		queryURL := q.getURLQuery(req)
+		matches := q.regexp.FindStringSubmatchIndex(queryURL)
+		if len(matches) > 0 {
+			extractVars(queryURL, matches, q.varsN, m.Vars)
+		}
+	}
+}
+
+// getHost tries its best to return the request host.
+// According to section 14.23 of RFC 2616 the Host header
+// can include the port number if the default value of 80 is not used.
+func getHost(r *http.Request) string {
+	if r.URL.IsAbs() {
+		return r.URL.Host
+	}
+	return r.Host
+}
+
+func extractVars(input string, matches []int, names []string, output map[string]string) {
+	for i, name := range names {
+		output[name] = input[matches[2*i+2]:matches[2*i+3]]
+	}
+}