Implement has() function to determine if an element at a JSONPath exists

README.md

@@ -20,12 +20,13 @@ core applications: https://status.twinnation.org/
 
 - [Features](#features)
 - [Usage](#usage)
-  - [Configuration](#configuration)
+- [Configuration](#configuration)
   - [Conditions](#conditions)
     - [Placeholders](#placeholders)
     - [Functions](#functions)
   - [Alerting](#alerting)
     - [Configuring Slack alerts](#configuring-slack-alerts)
+    - [Configuring Discord alerts](#configuring-discord-alerts)
     - [Configuring PagerDuty alerts](#configuring-pagerduty-alerts)
     - [Configuring Twilio alerts](#configuring-twilio-alerts)
     - [Configuring Mattermost alerts](#configuring-mattermost-alerts)
@@ -84,7 +85,7 @@ services:
       - "[RESPONSE_TIME] < 300"   # Response time must be under 300ms
   - name: example
     url: "https://example.org/"
-    interval: 30s
+    interval: 5m
     conditions:
       - "[STATUS] == 200"
 ```
@@ -93,10 +94,10 @@ This example would look like this:
 
 ![Simple example](.github/assets/example.png)
 
-Note that you can also add environment variables in the configuration file (i.e. `$DOMAIN`, `${DOMAIN}`)
+Note that you can also add environment variables in the configuration file (e.g. `$DOMAIN`, `${DOMAIN}`)
 
 
-### Configuration
+## Configuration
 
 | Parameter                                | Description                                                                   | Default        |
 |:---------------------------------------- |:----------------------------------------------------------------------------- |:-------------- |
@@ -110,43 +111,21 @@ Note that you can also add environment variables in the configuration file (i.e.
 | `services[].url`                         | URL to send the request to                                                    | Required `""`  |
 | `services[].method`                      | Request method                                                                | `GET`          |
 | `services[].insecure`                    | Whether to skip verifying the server's certificate chain and host name        | `false`        |
-| `services[].conditions`                  | Conditions used to determine the health of the service                        | `[]`           |
+| `services[].conditions`                  | Conditions used to determine the health of the service. See [Conditions](#conditions) | `[]`           |
 | `services[].interval`                    | Duration to wait between every status check                                   | `60s`          |
 | `services[].graphql`                     | Whether to wrap the body in a query param (`{"query":"$body"}`)               | `false`        |
 | `services[].body`                        | Request body                                                                  | `""`           |
 | `services[].headers`                     | Request headers                                                               | `{}`           |
-| `services[].dns`                         | Configuration for a service of type DNS. See [Monitoring using DNS queries](#monitoring-using-dns-queries)  | `""`           |
+| `services[].dns`                         | Configuration for a service of type DNS. See [Monitoring a service using DNS queries](#monitoring-a-service-using-dns-queries). | `""`           |
 | `services[].dns.query-type`              | Query type for DNS service                                                    | `""`           |
 | `services[].dns.query-name`              | Query name for DNS service                                                    | `""`           |
-| `services[].alerts[].type`               | Type of alert. Valid types: `slack`, `pagerduty`, `twilio`, `mattermost`, `messagebird`, `custom` | Required `""`  |
+| `services[].alerts[].type`               | Type of alert. Valid types: `slack`, `discord`m `pagerduty`, `twilio`, `mattermost`, `messagebird`, `custom` | Required `""`  |
 | `services[].alerts[].enabled`            | Whether to enable the alert                                                   | `false`        |
 | `services[].alerts[].failure-threshold`  | Number of failures in a row needed before triggering the alert                | `3`            |
 | `services[].alerts[].success-threshold`  | Number of successes in a row before an ongoing incident is marked as resolved | `2`            |
 | `services[].alerts[].send-on-resolved`   | Whether to send a notification once a triggered alert is marked as resolved   | `false`        |
 | `services[].alerts[].description`        | Description of the alert. Will be included in the alert sent                  | `""`           |
-| `alerting`                               | Configuration for alerting                                                    | `{}`           |
+| `alerting`                               | Configuration for alerting. See [Alerting](#alerting)                         | `{}`           |
-| `alerting.slack`                         | Configuration for alerts of type `slack`                                      | `{}`           |
-| `alerting.slack.webhook-url`             | Slack Webhook URL                                                             | Required `""`  |
-| `alerting.pagerduty`                     | Configuration for alerts of type `pagerduty`                                  | `{}`           |
-| `alerting.pagerduty.integration-key`     | PagerDuty Events API v2 integration key.                                      | Required `""`  |
-| `alerting.twilio`                        | Settings for alerts of type `twilio`                                          | `{}`           |
-| `alerting.twilio.sid`                    | Twilio account SID                                                            | Required `""`  |
-| `alerting.twilio.token`                  | Twilio auth token                                                             | Required `""`  |
-| `alerting.twilio.from`                   | Number to send Twilio alerts from                                             | Required `""`  |
-| `alerting.twilio.to`                     | Number to send twilio alerts to                                               | Required `""`  |
-| `alerting.mattermost`                    | Configuration for alerts of type `mattermost`                                 | `{}`           |
-| `alerting.mattermost.webhook-url`        | Mattermost Webhook URL                                                        | Required `""`  |
-| `alerting.mattermost.insecure`           | Whether to skip verifying the server's certificate chain and host name        | `false`        |
-| `alerting.messagebird`                   | Settings for alerts of type `messagebird`                                     | `{}`           |
-| `alerting.messagebird.access-key`        | Messagebird access key                                                        | Required `""`  |
-| `alerting.messagebird.originator`        | The sender of the message                                                     | Required `""`  |
-| `alerting.messagebird.recipients`        | The recipients of the message                                                 | Required `""`  |
-| `alerting.custom`                        | Configuration for custom actions on failure or alerts                         | `{}`           |
-| `alerting.custom.url`                    | Custom alerting request url                                                   | Required `""`  |
-| `alerting.custom.method`                 | Request method                                                                | `GET`          |
-| `alerting.custom.insecure`               | Whether to skip verifying the server's certificate chain and host name        | `false`        |
-| `alerting.custom.body`                   | Custom alerting request body.                                                 | `""`           |
-| `alerting.custom.headers`                | Custom alerting request headers                                               | `{}`           |
 | `security`                               | Security configuration                                                        | `{}`           |
 | `security.basic`                         | Basic authentication security configuration                                   | `{}`           |
 | `security.basic.username`                | Username for Basic authentication                                             | Required `""`  |
@@ -156,7 +135,8 @@ Note that you can also add environment variables in the configuration file (i.e.
 | `web.address`                            | Address to listen on                                                          | `0.0.0.0`      |
 | `web.port`                               | Port to listen on                                                             | `8080`         |
 
-For Kubernetes configuration, see [Kubernetes](#kubernetes-alpha)
+- For Kubernetes configuration, see [Kubernetes](#kubernetes-alpha).
+- For alerting configuration, see [Alerting](#alerting).
 
 
 ### Conditions
@@ -179,6 +159,8 @@ Here are some examples of conditions you can use:
 | `[BODY].age == [BODY].id`    | JSONPath value of `$.age` is equal JSONPath `$.id`      | `{"age":1,"id":1}`         |  |
 | `len([BODY].data) < 5`       | Array at JSONPath `$.data` has less than 5 elements     | `{"data":[{"id":1}]}`      |  |
 | `len([BODY].name) == 8`      | String at JSONPath `$.name` has a length of 8           | `{"name":"john.doe"}`      | `{"name":"bob"}` |
+| `has([BODY].errors) == false` | JSONPath `$.errors` does not exist                     | `{"name":"john.doe"}`      | `{"errors":[]}` |
+| `has([BODY].users) == true`  | JSONPath `$.users` exists                               | `{"users":[]}`             | `{}` |
 | `[BODY].name == pat(john*)`  | String at JSONPath `$.name` matches pattern `john*`     | `{"name":"john.doe"}`      | `{"name":"bob"}` |
 | `[BODY].id == any(1, 2)`     | Value at JSONPath `$.id` is equal to `1` or `2`         | 1, 2                       | 3, 4, 5 |
 | `[CERTIFICATE_EXPIRATION] > 48h` | Certificate expiration is more than 48h away        | 49h, 50h, 123h             | 1h, 24h, ... |
@@ -202,6 +184,7 @@ Here are some examples of conditions you can use:
 | Function   | Description                                                                                                      | Example                    |
 |:-----------|:---------------------------------------------------------------------------------------------------------------- |:-------------------------- |
 | `len`      | Returns the length of the object/slice. Works only with the `[BODY]` placeholder.                                | `len([BODY].username) > 8`
+| `has`      | Returns `true` or `false` based on whether a given path is valid. Works only with the `[BODY]` placeholder.      | `has([BODY].errors) == false`
 | `pat`      | Specifies that the string passed as parameter should be evaluated as a pattern. Works only with `==` and `!=`.   | `[IP] == pat(192.168.*)`
 | `any`      | Specifies that any one of the values passed as parameters is a valid value. Works only with `==` and `!=`.       | `[BODY].ip == any(127.0.0.1, ::1)`
 
@@ -216,6 +199,33 @@ individual services with configurable descriptions and thresholds.
 Note that if an alerting provider is not configured properly, all alerts configured with the provider's type will be
 ignored.
 
+| Parameter                                | Description                                                                   | Default        |
+|:---------------------------------------- |:----------------------------------------------------------------------------- |:-------------- |
+| `alerting.slack`                         | Configuration for alerts of type `slack`                                      | `{}`           |
+| `alerting.slack.webhook-url`             | Slack Webhook URL                                                             | Required `""`  |
+| `alerting.discord`                       | Configuration for alerts of type `discord`                                    | `{}`           |
+| `alerting.discord.webhook-url`           | Discord Webhook URL                                                           | Required `""`  |
+| `alerting.pagerduty`                     | Configuration for alerts of type `pagerduty`                                  | `{}`           |
+| `alerting.pagerduty.integration-key`     | PagerDuty Events API v2 integration key.                                      | Required `""`  |
+| `alerting.twilio`                        | Settings for alerts of type `twilio`                                          | `{}`           |
+| `alerting.twilio.sid`                    | Twilio account SID                                                            | Required `""`  |
+| `alerting.twilio.token`                  | Twilio auth token                                                             | Required `""`  |
+| `alerting.twilio.from`                   | Number to send Twilio alerts from                                             | Required `""`  |
+| `alerting.twilio.to`                     | Number to send twilio alerts to                                               | Required `""`  |
+| `alerting.mattermost`                    | Configuration for alerts of type `mattermost`                                 | `{}`           |
+| `alerting.mattermost.webhook-url`        | Mattermost Webhook URL                                                        | Required `""`  |
+| `alerting.mattermost.insecure`           | Whether to skip verifying the server's certificate chain and host name        | `false`        |
+| `alerting.messagebird`                   | Settings for alerts of type `messagebird`                                     | `{}`           |
+| `alerting.messagebird.access-key`        | Messagebird access key                                                        | Required `""`  |
+| `alerting.messagebird.originator`        | The sender of the message                                                     | Required `""`  |
+| `alerting.messagebird.recipients`        | The recipients of the message                                                 | Required `""`  |
+| `alerting.custom`                        | Configuration for custom actions on failure or alerts                         | `{}`           |
+| `alerting.custom.url`                    | Custom alerting request url                                                   | Required `""`  |
+| `alerting.custom.method`                 | Request method                                                                | `GET`          |
+| `alerting.custom.insecure`               | Whether to skip verifying the server's certificate chain and host name        | `false`        |
+| `alerting.custom.body`                   | Custom alerting request body.                                                 | `""`           |
+| `alerting.custom.headers`                | Custom alerting request headers                                               | `{}`           |
+
 
 #### Configuring Slack alerts
 
@@ -223,6 +233,7 @@ ignored.
 alerting:
   slack: 
     webhook-url: "https://hooks.slack.com/services/**********/**********/**********"
+
 services:
   - name: twinnation
     url: "https://twinnation.org/health"
@@ -248,6 +259,29 @@ Here's an example of what the notifications look like:
 ![Slack notifications](.github/assets/slack-alerts.png)
 
 
+#### Configuring Discord alerts
+
+```yaml
+alerting:
+  discord: 
+    webhook-url: "https://discord.com/api/webhooks/**********/**********"
+
+services:
+  - name: twinnation
+    url: "https://twinnation.org/health"
+    interval: 30s
+    alerts:
+      - type: discord
+        enabled: true
+        description: "healthcheck failed"
+        send-on-resolved: true
+    conditions:
+      - "[STATUS] == 200"
+      - "[BODY].status == UP"
+      - "[RESPONSE_TIME] < 300"
+```
+
+
 #### Configuring PagerDuty alerts
 
 It is highly recommended to set `services[].alerts[].send-on-resolved` to `true` for alerts 
@@ -259,6 +293,7 @@ PagerDuty instead.
 alerting:
   pagerduty: 
     integration-key: "********************************"
+
 services:
   - name: twinnation
     url: "https://twinnation.org/health"
@@ -269,7 +304,7 @@ services:
         failure-threshold: 3
         success-threshold: 5
         send-on-resolved: true
-        description: "healthcheck failed 3 times in a row"
+        description: "healthcheck failed"
     conditions:
       - "[STATUS] == 200"
       - "[BODY].status == UP"
@@ -286,6 +321,7 @@ alerting:
     token: "..."
     from: "+1-234-567-8901"
     to: "+1-234-567-8901"
+
 services:
   - name: twinnation
     interval: 30s
@@ -295,7 +331,7 @@ services:
         enabled: true
         failure-threshold: 5
         send-on-resolved: true
-        description: "healthcheck failed 5 times in a row"
+        description: "healthcheck failed"
     conditions:
       - "[STATUS] == 200"
       - "[BODY].status == UP"
@@ -310,6 +346,7 @@ alerting:
   mattermost: 
     webhook-url: "http://**********/hooks/**********"
     insecure: true
+
 services:
   - name: twinnation
     url: "https://twinnation.org/health"
@@ -317,7 +354,7 @@ services:
     alerts:
       - type: mattermost
         enabled: true
-        description: "healthcheck failed 3 times in a row"
+        description: "healthcheck failed"
         send-on-resolved: true
     conditions:
       - "[STATUS] == 200"
@@ -349,7 +386,7 @@ services:
         enabled: true
         failure-threshold: 3
         send-on-resolved: true
-        description: "healthcheck failed 3 times in a row"
+        description: "healthcheck failed"
     conditions:
       - "[STATUS] == 200"
       - "[BODY].status == UP"
@@ -395,7 +432,7 @@ services:
         failure-threshold: 10
         success-threshold: 3
         send-on-resolved: true
-        description: "healthcheck failed 10 times in a row"
+        description: "healthcheck failed"
     conditions:
       - "[STATUS] == 200"
       - "[BODY].status == UP"
@@ -414,6 +451,7 @@ alerting:
 As a result, the `[ALERT_TRIGGERED_OR_RESOLVED]` in the body of first example of this section would be replaced by 
 `partial_outage` when an alert is triggered and `operational` when an alert is resolved.
 
+
 ### Kubernetes (ALPHA)
 
 > **WARNING**: This feature is in ALPHA. This means that it is very likely to change in the near future, which means that
@@ -527,8 +565,6 @@ services:
           avatar
         }
       }
-    headers:
-      Content-Type: application/json # XXX: as of v1.9.2, this header is automatically added when graphql is set to true
     conditions:
       - "[STATUS] == 200"
       - "[BODY].data.users[0].gender == female"

alerting/config.go

@@ -2,6 +2,7 @@ package alerting
 
 import (
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/alerting/provider/discord"
 	"github.com/TwinProduction/gatus/alerting/provider/mattermost"
 	"github.com/TwinProduction/gatus/alerting/provider/messagebird"
 	"github.com/TwinProduction/gatus/alerting/provider/pagerduty"
@@ -11,8 +12,11 @@ import (
 
 // Config is the configuration for alerting providers
 type Config struct {
-	// Slack is the configuration for the slack alerting provider
+	// Custom is the configuration for the custom alerting provider
-	Slack *slack.AlertProvider `yaml:"slack"`
+	Custom *custom.AlertProvider `yaml:"custom"`
+
+	// Discord is the configuration for the discord alerting provider
+	Discord *discord.AlertProvider `yaml:"discord"`
 
 	// Mattermost is the configuration for the mattermost alerting provider
 	Mattermost *mattermost.AlertProvider `yaml:"mattermost"`
@@ -20,12 +24,12 @@ type Config struct {
 	// Messagebird is the configuration for the messagebird alerting provider
 	Messagebird *messagebird.AlertProvider `yaml:"messagebird"`
 
-	// Pagerduty is the configuration for the pagerduty alerting provider
+	// PagerDuty is the configuration for the pagerduty alerting provider
 	PagerDuty *pagerduty.AlertProvider `yaml:"pagerduty"`
 
+	// Slack is the configuration for the slack alerting provider
+	Slack *slack.AlertProvider `yaml:"slack"`
+
 	// Twilio is the configuration for the twilio alerting provider
 	Twilio *twilio.AlertProvider `yaml:"twilio"`
-
-	// Custom is the configuration for the custom alerting provider
-	Custom *custom.AlertProvider `yaml:"custom"`
 }

alerting/provider/discord/discord.go

@@ -0,0 +1,63 @@
+package discord
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/core"
+)
+
+// AlertProvider is the configuration necessary for sending an alert using Discord
+type AlertProvider struct {
+	WebhookURL string `yaml:"webhook-url"`
+}
+
+// IsValid returns whether the provider's configuration is valid
+func (provider *AlertProvider) IsValid() bool {
+	return len(provider.WebhookURL) > 0
+}
+
+// ToCustomAlertProvider converts the provider into a custom.AlertProvider
+func (provider *AlertProvider) ToCustomAlertProvider(service *core.Service, alert *core.Alert, result *core.Result, resolved bool) *custom.AlertProvider {
+	var message, results string
+	var colorCode int
+	if resolved {
+		message = fmt.Sprintf("An alert for **%s** has been resolved after passing successfully %d time(s) in a row", service.Name, alert.SuccessThreshold)
+		colorCode = 3066993
+	} else {
+		message = fmt.Sprintf("An alert for **%s** has been triggered due to having failed %d time(s) in a row", service.Name, alert.FailureThreshold)
+		colorCode = 15158332
+	}
+	for _, conditionResult := range result.ConditionResults {
+		var prefix string
+		if conditionResult.Success {
+			prefix = ":white_check_mark:"
+		} else {
+			prefix = ":x:"
+		}
+		results += fmt.Sprintf("%s - `%s`\\n", prefix, conditionResult.Condition)
+	}
+	return &custom.AlertProvider{
+		URL:    provider.WebhookURL,
+		Method: http.MethodPost,
+		Body: fmt.Sprintf(`{
+  "content": "",
+  "embeds": [
+    {
+      "title": ":helmet_with_white_cross: Gatus",
+      "description": "%s:\n> %s",
+      "color": %d,
+      "fields": [
+        {
+          "name": "Condition results",
+          "value": "%s",
+          "inline": false
+        }
+      ]
+    }
+  ]
+}`, message, alert.Description, colorCode, results),
+		Headers: map[string]string{"Content-Type": "application/json"},
+	}
+}

alerting/provider/discord/discord_test.go

@@ -0,0 +1,65 @@
+package discord
+
+import (
+	"encoding/json"
+	"net/http"
+	"strings"
+	"testing"
+
+	"github.com/TwinProduction/gatus/core"
+)
+
+func TestAlertProvider_IsValid(t *testing.T) {
+	invalidProvider := AlertProvider{WebhookURL: ""}
+	if invalidProvider.IsValid() {
+		t.Error("provider shouldn't have been valid")
+	}
+	validProvider := AlertProvider{WebhookURL: "http://example.com"}
+	if !validProvider.IsValid() {
+		t.Error("provider should've been valid")
+	}
+}
+
+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.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.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/provider.go

@@ -2,6 +2,7 @@ package provider
 
 import (
 	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/alerting/provider/discord"
 	"github.com/TwinProduction/gatus/alerting/provider/mattermost"
 	"github.com/TwinProduction/gatus/alerting/provider/messagebird"
 	"github.com/TwinProduction/gatus/alerting/provider/pagerduty"
@@ -22,9 +23,10 @@ type AlertProvider interface {
 var (
 	// Validate interface implementation on compile
 	_ AlertProvider = (*custom.AlertProvider)(nil)
-	_ AlertProvider = (*twilio.AlertProvider)(nil)
+	_ AlertProvider = (*discord.AlertProvider)(nil)
-	_ AlertProvider = (*slack.AlertProvider)(nil)
 	_ AlertProvider = (*mattermost.AlertProvider)(nil)
 	_ AlertProvider = (*messagebird.AlertProvider)(nil)
 	_ AlertProvider = (*pagerduty.AlertProvider)(nil)
+	_ AlertProvider = (*slack.AlertProvider)(nil)
+	_ AlertProvider = (*twilio.AlertProvider)(nil)
 )

config/config.go

@@ -228,12 +228,13 @@ func validateAlertingConfig(config *Config) {
 		return
 	}
 	alertTypes := []core.AlertType{
-		core.SlackAlert,
+		core.CustomAlert,
+		core.DiscordAlert,
 		core.MattermostAlert,
 		core.MessagebirdAlert,
-		core.TwilioAlert,
 		core.PagerDutyAlert,
-		core.CustomAlert,
+		core.SlackAlert,
+		core.TwilioAlert,
 	}
 	var validProviders, invalidProviders []core.AlertType
 	for _, alertType := range alertTypes {
@@ -255,12 +256,18 @@ func validateAlertingConfig(config *Config) {
 // GetAlertingProviderByAlertType returns an provider.AlertProvider by its corresponding core.AlertType
 func GetAlertingProviderByAlertType(config *Config, alertType core.AlertType) provider.AlertProvider {
 	switch alertType {
-	case core.SlackAlert:
+	case core.CustomAlert:
-		if config.Alerting.Slack == nil {
+		if config.Alerting.Custom == nil {
 			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
 			return nil
 		}
-		return config.Alerting.Slack
+		return config.Alerting.Custom
+	case core.DiscordAlert:
+		if config.Alerting.Discord == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Alerting.Discord
 	case core.MattermostAlert:
 		if config.Alerting.Mattermost == nil {
 			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
@@ -273,24 +280,24 @@ func GetAlertingProviderByAlertType(config *Config, alertType core.AlertType) pr
 			return nil
 		}
 		return config.Alerting.Messagebird
-	case core.TwilioAlert:
-		if config.Alerting.Twilio == nil {
-			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
-			return nil
-		}
-		return config.Alerting.Twilio
 	case core.PagerDutyAlert:
 		if config.Alerting.PagerDuty == nil {
 			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
 			return nil
 		}
 		return config.Alerting.PagerDuty
-	case core.CustomAlert:
+	case core.SlackAlert:
-		if config.Alerting.Custom == nil {
+		if config.Alerting.Slack == nil {
 			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
 			return nil
 		}
-		return config.Alerting.Custom
+		return config.Alerting.Slack
+	case core.TwilioAlert:
+		if config.Alerting.Twilio == nil {
+			// Since we're returning an interface, we need to explicitly return nil, even if the provider itself is nil
+			return nil
+		}
+		return config.Alerting.Twilio
 	}
 	return nil
 }

config/config_test.go

@@ -6,6 +6,14 @@ import (
 	"testing"
 	"time"
 
+	"github.com/TwinProduction/gatus/alerting"
+	"github.com/TwinProduction/gatus/alerting/provider/custom"
+	"github.com/TwinProduction/gatus/alerting/provider/discord"
+	"github.com/TwinProduction/gatus/alerting/provider/mattermost"
+	"github.com/TwinProduction/gatus/alerting/provider/messagebird"
+	"github.com/TwinProduction/gatus/alerting/provider/pagerduty"
+	"github.com/TwinProduction/gatus/alerting/provider/slack"
+	"github.com/TwinProduction/gatus/alerting/provider/twilio"
 	"github.com/TwinProduction/gatus/core"
 	"github.com/TwinProduction/gatus/k8stest"
 	v1 "k8s.io/api/core/v1"
@@ -338,6 +346,8 @@ debug: true
 alerting:
   slack:
     webhook-url: "http://example.com"
+  discord:
+    webhook-url: "http://example.org"
   pagerduty:
     integration-key: "00000000000000000000000000000000"
   messagebird:
@@ -356,7 +366,9 @@ services:
         success-threshold: 5
         description: "Healthcheck failed 7 times in a row"
       - type: messagebird
+      - type: discord
         enabled: true
+        failure-threshold: 10
     conditions:
       - "[STATUS] == 200"
 `))
@@ -369,6 +381,7 @@ services:
 	if config.Metrics {
 		t.Error("Metrics should've been false by default")
 	}
+	// Alerting providers
 	if config.Alerting == nil {
 		t.Fatal("config.Alerting shouldn't have been nil")
 	}
@@ -396,6 +409,16 @@ services:
 	if config.Alerting.Messagebird.Recipients != "31619191919" {
 		t.Errorf("Messagebird to recipients should've been %s, but was %s", "31619191919", config.Alerting.Messagebird.Recipients)
 	}
+	if config.Alerting.Discord == nil || !config.Alerting.Discord.IsValid() {
+		t.Fatal("Discord alerting config should've been valid")
+	}
+	if config.Alerting.Discord.WebhookURL != "http://example.org" {
+		t.Errorf("Discord webhook should've been %s, but was %s", "http://example.org", config.Alerting.Discord.WebhookURL)
+	}
+	if GetAlertingProviderByAlertType(config, core.DiscordAlert) != config.Alerting.Discord {
+		t.Error("expected discord configuration")
+	}
+	// Services
 	if len(config.Services) != 1 {
 		t.Error("There should've been 1 service")
 	}
@@ -405,11 +428,12 @@ services:
 	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.Services[0].Alerts == nil {
+	if len(config.Services[0].Alerts) != 4 {
-		t.Fatal("The service alerts shouldn't have been nil")
+		t.Fatal("There should've been 4 alerts configured")
 	}
-	if len(config.Services[0].Alerts) != 3 {
+
-		t.Fatal("There should've been 3 alert configured")
+	if config.Services[0].Alerts[0].Type != core.SlackAlert {
+		t.Errorf("The type of the alert should've been %s, but it was %s", core.SlackAlert, config.Services[0].Alerts[0].Type)
 	}
 	if !config.Services[0].Alerts[0].Enabled {
 		t.Error("The alert should've been enabled")
@@ -420,23 +444,35 @@ services:
 	if config.Services[0].Alerts[0].SuccessThreshold != 2 {
 		t.Errorf("The default success threshold of the alert should've been %d, but it was %d", 2, config.Services[0].Alerts[0].SuccessThreshold)
 	}
+
+	if config.Services[0].Alerts[1].Type != core.PagerDutyAlert {
+		t.Errorf("The type of the alert should've been %s, but it was %s", core.PagerDutyAlert, config.Services[0].Alerts[1].Type)
+	}
+	if config.Services[0].Alerts[1].Description != "Healthcheck failed 7 times in a row" {
+		t.Errorf("The description of the alert should've been %s, but it was %s", "Healthcheck failed 7 times in a row", config.Services[0].Alerts[1].Description)
+	}
 	if config.Services[0].Alerts[1].FailureThreshold != 7 {
 		t.Errorf("The failure threshold of the alert should've been %d, but it was %d", 7, config.Services[0].Alerts[1].FailureThreshold)
 	}
 	if config.Services[0].Alerts[1].SuccessThreshold != 5 {
 		t.Errorf("The success threshold of the alert should've been %d, but it was %d", 5, config.Services[0].Alerts[1].SuccessThreshold)
 	}
-	if config.Services[0].Alerts[0].Type != core.SlackAlert {
+
-		t.Errorf("The type of the alert should've been %s, but it was %s", core.SlackAlert, config.Services[0].Alerts[0].Type)
-	}
-	if config.Services[0].Alerts[1].Type != core.PagerDutyAlert {
-		t.Errorf("The type of the alert should've been %s, but it was %s", core.PagerDutyAlert, config.Services[0].Alerts[1].Type)
-	}
-	if config.Services[0].Alerts[1].Description != "Healthcheck failed 7 times in a row" {
-		t.Errorf("The description of the alert should've been %s, but it was %s", "Healthcheck failed 7 times in a row", config.Services[0].Alerts[0].Description)
-	}
 	if config.Services[0].Alerts[2].Type != core.MessagebirdAlert {
-		t.Errorf("The type of the alert should've been %s, but it was %s", core.MessagebirdAlert, config.Services[0].Alerts[1].Type)
+		t.Errorf("The type of the alert should've been %s, but it was %s", core.MessagebirdAlert, config.Services[0].Alerts[2].Type)
+	}
+	if config.Services[0].Alerts[2].Enabled {
+		t.Error("The alert should've been disabled")
+	}
+
+	if config.Services[0].Alerts[3].Type != core.DiscordAlert {
+		t.Errorf("The type of the alert should've been %s, but it was %s", core.DiscordAlert, config.Services[0].Alerts[3].Type)
+	}
+	if config.Services[0].Alerts[3].FailureThreshold != 10 {
+		t.Errorf("The failure threshold of the alert should've been %d, but it was %d", 10, config.Services[0].Alerts[3].FailureThreshold)
+	}
+	if config.Services[0].Alerts[3].SuccessThreshold != 2 {
+		t.Errorf("The default success threshold of the alert should've been %d, but it was %d", 2, config.Services[0].Alerts[3].SuccessThreshold)
 	}
 }
 
@@ -809,3 +845,38 @@ kubernetes:
 	// TODO: find a way to test this?
 	t.Error("Function should've panicked because testing with ClusterModeIn isn't supported")
 }
+
+func TestGetAlertingProviderByAlertType(t *testing.T) {
+	cfg := &Config{
+		Alerting: &alerting.Config{
+			Custom:      &custom.AlertProvider{},
+			Discord:     &discord.AlertProvider{},
+			Mattermost:  &mattermost.AlertProvider{},
+			Messagebird: &messagebird.AlertProvider{},
+			PagerDuty:   &pagerduty.AlertProvider{},
+			Slack:       &slack.AlertProvider{},
+			Twilio:      &twilio.AlertProvider{},
+		},
+	}
+	if GetAlertingProviderByAlertType(cfg, core.CustomAlert) != cfg.Alerting.Custom {
+		t.Error("expected Custom configuration")
+	}
+	if GetAlertingProviderByAlertType(cfg, core.DiscordAlert) != cfg.Alerting.Discord {
+		t.Error("expected Discord configuration")
+	}
+	if GetAlertingProviderByAlertType(cfg, core.MattermostAlert) != cfg.Alerting.Mattermost {
+		t.Error("expected Mattermost configuration")
+	}
+	if GetAlertingProviderByAlertType(cfg, core.MessagebirdAlert) != cfg.Alerting.Messagebird {
+		t.Error("expected Messagebird configuration")
+	}
+	if GetAlertingProviderByAlertType(cfg, core.PagerDutyAlert) != cfg.Alerting.PagerDuty {
+		t.Error("expected PagerDuty configuration")
+	}
+	if GetAlertingProviderByAlertType(cfg, core.SlackAlert) != cfg.Alerting.Slack {
+		t.Error("expected Slack configuration")
+	}
+	if GetAlertingProviderByAlertType(cfg, core.TwilioAlert) != cfg.Alerting.Twilio {
+		t.Error("expected Twilio configuration")
+	}
+}

controller/controller.go

@@ -26,7 +26,7 @@ const (
 )
 
 var (
-	cache = gocache.NewCache().WithMaxSize(100).WithEvictionPolicy(gocache.LeastRecentlyUsed)
+	cache = gocache.NewCache().WithMaxSize(100).WithEvictionPolicy(gocache.FirstInFirstOut)
 
 	// 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

controller/controller_test.go

@@ -38,7 +38,6 @@ var (
 		Hostname:              "example.org",
 		IP:                    "127.0.0.1",
 		HTTPStatus:            200,
-		Body:                  []byte("body"),
 		Errors:                nil,
 		Connected:             true,
 		Success:               true,
@@ -64,7 +63,6 @@ var (
 		Hostname:              "example.org",
 		IP:                    "127.0.0.1",
 		HTTPStatus:            200,
-		Body:                  []byte("body"),
 		Errors:                []string{"error-1", "error-2"},
 		Connected:             true,
 		Success:               false,

core/alert.go

@@ -40,8 +40,11 @@ type Alert struct {
 type AlertType string
 
 const (
-	// SlackAlert is the AlertType for the slack alerting provider
+	// CustomAlert is the AlertType for the custom alerting provider
-	SlackAlert AlertType = "slack"
+	CustomAlert AlertType = "custom"
+
+	// DiscordAlert is the AlertType for the discord alerting provider
+	DiscordAlert AlertType = "discord"
 
 	// MattermostAlert is the AlertType for the mattermost alerting provider
 	MattermostAlert AlertType = "mattermost"
@@ -52,9 +55,9 @@ const (
 	// PagerDutyAlert is the AlertType for the pagerduty alerting provider
 	PagerDutyAlert AlertType = "pagerduty"
 
+	// SlackAlert is the AlertType for the slack alerting provider
+	SlackAlert AlertType = "slack"
+
 	// TwilioAlert is the AlertType for the twilio alerting provider
 	TwilioAlert AlertType = "twilio"
-
-	// CustomAlert is the AlertType for the custom alerting provider
-	CustomAlert AlertType = "custom"
 )

core/condition.go

@@ -23,7 +23,7 @@ const (
 
 	// DNSRCodePlaceholder is a place holder for DNS_RCODE
 	//
-	// Values that could be NOERROR, FORMERR, SERVFAIL, NXDOMAIN, NOTIMP and REFUSED
+	// Values that could replace the placeholder: NOERROR, FORMERR, SERVFAIL, NXDOMAIN, NOTIMP, REFUSED
 	DNSRCodePlaceholder = "[DNS_RCODE]"
 
 	// ResponseTimePlaceholder is a placeholder for the request response time, in milliseconds.
@@ -51,14 +51,19 @@ const (
 	// Usage: len([BODY].articles) == 10, len([BODY].name) > 5
 	LengthFunctionPrefix = "len("
 
+	// HasFunctionPrefix is the prefix for the has function
+	//
+	// Usage: has([BODY].errors) == true
+	HasFunctionPrefix = "has("
+
 	// PatternFunctionPrefix is the prefix for the pattern function
 	//
-	// Usage: pat(192.168.*.*)
+	// Usage: [IP] == pat(192.168.*.*)
 	PatternFunctionPrefix = "pat("
 
 	// AnyFunctionPrefix is the prefix for the any function
 	//
-	// Usage: any(1.1.1.1, 1.0.0.1)
+	// Usage: [IP] == any(1.1.1.1, 1.0.0.1)
 	AnyFunctionPrefix = "any("
 
 	// FunctionSuffix is the suffix for all functions
@@ -123,6 +128,12 @@ func (c Condition) evaluate(result *Result) bool {
 	return success
 }
 
+// hasBodyPlaceholder checks whether the condition has a BodyPlaceholder
+// Used for determining whether the response body should be read or not
+func (c Condition) hasBodyPlaceholder() bool {
+	return strings.Contains(string(c), BodyPlaceholder)
+}
+
 // isEqual compares two strings.
 //
 // Supports the pattern and the any functions.
@@ -181,7 +192,7 @@ func isEqual(first, second string) bool {
 func sanitizeAndResolve(elements []string, result *Result) ([]string, []string) {
 	parameters := make([]string, len(elements))
 	resolvedParameters := make([]string, len(elements))
-	body := strings.TrimSpace(string(result.Body))
+	body := strings.TrimSpace(string(result.body))
 	for i, element := range elements {
 		element = strings.TrimSpace(element)
 		parameters[i] = element
@@ -203,26 +214,39 @@ func sanitizeAndResolve(elements []string, result *Result) ([]string, []string)
 		default:
 			// if contains the BodyPlaceholder, then evaluate json path
 			if strings.Contains(element, BodyPlaceholder) {
-				wantLength := false
+				checkingForLength := false
+				checkingForExistence := false
 				if strings.HasPrefix(element, LengthFunctionPrefix) && strings.HasSuffix(element, FunctionSuffix) {
-					wantLength = true
+					checkingForLength = true
 					element = strings.TrimSuffix(strings.TrimPrefix(element, LengthFunctionPrefix), FunctionSuffix)
 				}
-				resolvedElement, resolvedElementLength, err := jsonpath.Eval(strings.TrimPrefix(element, BodyPlaceholder+"."), result.Body)
+				if strings.HasPrefix(element, HasFunctionPrefix) && strings.HasSuffix(element, FunctionSuffix) {
-				if err != nil {
+					checkingForExistence = true
-					if err.Error() != "unexpected end of JSON input" {
+					element = strings.TrimSuffix(strings.TrimPrefix(element, HasFunctionPrefix), FunctionSuffix)
-						result.Errors = append(result.Errors, err.Error())
+				}
-					}
+				resolvedElement, resolvedElementLength, err := jsonpath.Eval(strings.TrimPrefix(element, BodyPlaceholder+"."), result.body)
-					if wantLength {
+				if checkingForExistence {
-						element = LengthFunctionPrefix + element + FunctionSuffix + " " + InvalidConditionElementSuffix
+					if err != nil {
+						element = "false"
 					} else {
-						element = element + " " + InvalidConditionElementSuffix
+						element = "true"
 					}
 				} else {
-					if wantLength {
+					if err != nil {
-						element = strconv.Itoa(resolvedElementLength)
+						if err.Error() != "unexpected end of JSON input" {
+							result.Errors = append(result.Errors, err.Error())
+						}
+						if checkingForLength {
+							element = LengthFunctionPrefix + element + FunctionSuffix + " " + InvalidConditionElementSuffix
+						} else {
+							element = element + " " + InvalidConditionElementSuffix
+						}
 					} else {
-						element = resolvedElement
+						if checkingForLength {
+							element = strconv.Itoa(resolvedElementLength)
+						} else {
+							element = resolvedElement
+						}
 					}
 				}
 			}

core/condition_bench_test.go

@@ -5,7 +5,7 @@ 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\"}")}
+		result := &Result{body: []byte("{\"name\": \"john.doe\"}")}
 		condition.evaluate(result)
 	}
 	b.ReportAllocs()
@@ -14,7 +14,7 @@ func BenchmarkCondition_evaluateWithBodyStringAny(b *testing.B) {
 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\"}")}
+		result := &Result{body: []byte("{\"name\": \"bob.doe\"}")}
 		condition.evaluate(result)
 	}
 	b.ReportAllocs()
@@ -23,7 +23,7 @@ func BenchmarkCondition_evaluateWithBodyStringAnyFailure(b *testing.B) {
 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\"}")}
+		result := &Result{body: []byte("{\"name\": \"john.doe\"}")}
 		condition.evaluate(result)
 	}
 	b.ReportAllocs()
@@ -32,7 +32,7 @@ func BenchmarkCondition_evaluateWithBodyString(b *testing.B) {
 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\"}")}
+		result := &Result{body: []byte("{\"name\": \"bob.doe\"}")}
 		condition.evaluate(result)
 	}
 	b.ReportAllocs()
@@ -41,7 +41,7 @@ func BenchmarkCondition_evaluateWithBodyStringFailure(b *testing.B) {
 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\"}")}
+		result := &Result{body: []byte("{\"name\": \"john.doe\"}")}
 		condition.evaluate(result)
 	}
 	b.ReportAllocs()
@@ -50,7 +50,7 @@ func BenchmarkCondition_evaluateWithBodyStringLen(b *testing.B) {
 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\"}")}
+		result := &Result{body: []byte("{\"name\": \"bob.doe\"}")}
 		condition.evaluate(result)
 	}
 	b.ReportAllocs()

core/dns.go

@@ -60,26 +60,26 @@ func (d *DNS) query(url string, result *Result) {
 		switch rr.Header().Rrtype {
 		case dns.TypeA:
 			if a, ok := rr.(*dns.A); ok {
-				result.Body = []byte(a.A.String())
+				result.body = []byte(a.A.String())
 			}
 		case dns.TypeAAAA:
 			if aaaa, ok := rr.(*dns.AAAA); ok {
-				result.Body = []byte(aaaa.AAAA.String())
+				result.body = []byte(aaaa.AAAA.String())
 			}
 		case dns.TypeCNAME:
 			if cname, ok := rr.(*dns.CNAME); ok {
-				result.Body = []byte(cname.Target)
+				result.body = []byte(cname.Target)
 			}
 		case dns.TypeMX:
 			if mx, ok := rr.(*dns.MX); ok {
-				result.Body = []byte(mx.Mx)
+				result.body = []byte(mx.Mx)
 			}
 		case dns.TypeNS:
 			if ns, ok := rr.(*dns.NS); ok {
-				result.Body = []byte(ns.Ns)
+				result.body = []byte(ns.Ns)
 			}
 		default:
-			result.Body = []byte("query type is not supported yet")
+			result.body = []byte("query type is not supported yet")
 		}
 	}
 }

core/dns_test.go

@@ -91,12 +91,12 @@ func TestIntegrationQuery(t *testing.T) {
 
 			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)) {
+				if !pattern.Match(test.expectedBody, string(result.body)) {
-					t.Errorf("got %s, expected result %s,", string(result.Body), test.expectedBody)
+					t.Errorf("got %s, expected result %s,", string(result.body), test.expectedBody)
 				}
 			} else {
-				if string(result.Body) != test.expectedBody {
+				if string(result.body) != test.expectedBody {
-					t.Errorf("got %s, expected result %s,", string(result.Body), test.expectedBody)
+					t.Errorf("got %s, expected result %s,", string(result.body), test.expectedBody)
 				}
 			}
 		})

core/result.go

@@ -12,10 +12,7 @@ type Result struct {
 	// DNSRCode is the response code of a DNS query in a human readable format
 	DNSRCode string `json:"-"`
 
-	// Body is the response body
+	// Hostname extracted from Service.URL
-	Body []byte `json:"-"`
-
-	// Hostname extracted from the Service URL
 	Hostname string `json:"hostname"`
 
 	// IP resolved from the Service URL
@@ -41,4 +38,11 @@ type Result struct {
 
 	// CertificateExpiration is the duration before the certificate expires
 	CertificateExpiration time.Duration `json:"-"`
+
+	// body is the response body
+	//
+	// Note that this variable is only used during the evaluation of a service's health.
+	// This means that the call Service.EvaluateHealth both populates the body (if necessary)
+	// and sets it to nil after the evaluation has been completed.
+	body []byte
 }

core/service-status.go

@@ -58,22 +58,10 @@ func NewServiceStatus(service *Service) *ServiceStatus {
 	}
 }
 
-// ShallowCopy creates a shallow copy of ServiceStatus
+// WithResultPagination returns a shallow copy of the ServiceStatus with only the results
-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 {
+func (ss ServiceStatus) WithResultPagination(page, pageSize int) *ServiceStatus {
-	shallowCopy := ss.ShallowCopy()
+	shallowCopy := ss
 	numberOfResults := len(shallowCopy.Results)
 	start := numberOfResults - (page * pageSize)
 	end := numberOfResults - ((page - 1) * pageSize)
@@ -90,7 +78,7 @@ func (ss *ServiceStatus) WithResultPagination(page, pageSize int) *ServiceStatus
 	} else {
 		shallowCopy.Results = shallowCopy.Results[start:end]
 	}
-	return shallowCopy
+	return &shallowCopy
 }
 
 // AddResult adds a Result to ServiceStatus.Results and makes sure that there are

core/service-status_bench_test.go

@@ -0,0 +1,92 @@
+package core
+
+import (
+	"testing"
+	"time"
+)
+
+var (
+	firstCondition  = Condition("[STATUS] == 200")
+	secondCondition = Condition("[RESPONSE_TIME] < 500")
+	thirdCondition  = Condition("[CERTIFICATE_EXPIRATION] < 72h")
+
+	timestamp = time.Now()
+
+	testService = Service{
+		Name:                    "name",
+		Group:                   "group",
+		URL:                     "https://example.org/what/ever",
+		Method:                  "GET",
+		Body:                    "body",
+		Interval:                30 * time.Second,
+		Conditions:              []*Condition{&firstCondition, &secondCondition, &thirdCondition},
+		Alerts:                  nil,
+		Insecure:                false,
+		NumberOfFailuresInARow:  0,
+		NumberOfSuccessesInARow: 0,
+	}
+	testSuccessfulResult = 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: []*ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   true,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   true,
+			},
+		},
+	}
+	testUnsuccessfulResult = 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: []*ConditionResult{
+			{
+				Condition: "[STATUS] == 200",
+				Success:   true,
+			},
+			{
+				Condition: "[RESPONSE_TIME] < 500",
+				Success:   false,
+			},
+			{
+				Condition: "[CERTIFICATE_EXPIRATION] < 72h",
+				Success:   false,
+			},
+		},
+	}
+)
+
+func BenchmarkServiceStatus_WithResultPagination(b *testing.B) {
+	service := &testService
+	serviceStatus := NewServiceStatus(service)
+	for i := 0; i < MaximumNumberOfResults; i++ {
+		serviceStatus.AddResult(&testSuccessfulResult)
+	}
+	for n := 0; n < b.N; n++ {
+		serviceStatus.WithResultPagination(1, 20)
+	}
+	b.ReportAllocs()
+}

core/service-status_test.go

@@ -26,7 +26,7 @@ func TestServiceStatus_AddResult(t *testing.T) {
 		serviceStatus.AddResult(&Result{Timestamp: time.Now()})
 	}
 	if len(serviceStatus.Results) != MaximumNumberOfResults {
-		t.Errorf("expected serviceStatus.Results to not exceed a length of 20")
+		t.Errorf("expected serviceStatus.Results to not exceed a length of %d", MaximumNumberOfResults)
 	}
 }
 

core/service.go

@@ -80,7 +80,7 @@ type Service struct {
 	// NumberOfFailuresInARow is the number of unsuccessful evaluations in a row
 	NumberOfFailuresInARow int
 
-	// NumberOfFailuresInARow is the number of successful evaluations in a row
+	// NumberOfSuccessesInARow is the number of successful evaluations in a row
 	NumberOfSuccessesInARow int
 }
 
@@ -149,6 +149,8 @@ func (service *Service) EvaluateHealth() *Result {
 		}
 	}
 	result.Timestamp = time.Now()
+	// No need to keep the body after the service has been evaluated
+	result.body = nil
 	return result
 }
 
@@ -220,9 +222,12 @@ func (service *Service) call(result *Result) {
 		}
 		result.HTTPStatus = response.StatusCode
 		result.Connected = response.StatusCode > 0
-		result.Body, err = ioutil.ReadAll(response.Body)
+		// Only read the body if there's a condition that uses the BodyPlaceholder
-		if err != nil {
+		if service.needsToReadBody() {
-			result.Errors = append(result.Errors, err.Error())
+			result.body, err = ioutil.ReadAll(response.Body)
+			if err != nil {
+				result.Errors = append(result.Errors, err.Error())
+			}
 		}
 	}
 }
@@ -247,3 +252,13 @@ func (service *Service) buildHTTPRequest() *http.Request {
 	}
 	return request
 }
+
+// needsToReadBody checks if there's any conditions that requires the response body to be read
+func (service *Service) needsToReadBody() bool {
+	for _, condition := range service.Conditions {
+		if condition.hasBodyPlaceholder() {
+			return true
+		}
+	}
+	return false
+}

core/service_test.go

@@ -10,7 +10,7 @@ import (
 func TestService_ValidateAndSetDefaults(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 		Alerts:     []*Alert{{Type: PagerDutyAlert}},
@@ -94,7 +94,7 @@ func TestService_ValidateAndSetDefaultsWithDNS(t *testing.T) {
 func TestService_GetAlertsTriggered(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 		Alerts:     []*Alert{{Type: PagerDutyAlert, Enabled: true}},
@@ -118,7 +118,7 @@ func TestService_GetAlertsTriggered(t *testing.T) {
 func TestService_buildHTTPRequest(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 	}
@@ -138,7 +138,7 @@ func TestService_buildHTTPRequest(t *testing.T) {
 func TestService_buildHTTPRequestWithCustomUserAgent(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 		Headers: map[string]string{
@@ -161,7 +161,7 @@ func TestService_buildHTTPRequestWithCustomUserAgent(t *testing.T) {
 func TestService_buildHTTPRequestWithHostHeader(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Method:     "POST",
 		Conditions: []*Condition{&condition},
@@ -182,13 +182,13 @@ func TestService_buildHTTPRequestWithHostHeader(t *testing.T) {
 func TestService_buildHTTPRequestWithGraphQLEnabled(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-graphql",
 		URL:        "https://twinnation.org/graphql",
 		Method:     "POST",
 		Conditions: []*Condition{&condition},
 		GraphQL:    true,
 		Body: `{
-  user(gender: "female") {
+  users(gender: "female") {
     id
     name
     gender
@@ -206,16 +206,17 @@ func TestService_buildHTTPRequestWithGraphQLEnabled(t *testing.T) {
 	}
 	body, _ := ioutil.ReadAll(request.Body)
 	if !strings.HasPrefix(string(body), "{\"query\":") {
-		t.Error("request.Body should've started with '{\"query\":', but it didn't:", string(body))
+		t.Error("request.body should've started with '{\"query\":', but it didn't:", string(body))
 	}
 }
 
 func TestIntegrationEvaluateHealth(t *testing.T) {
 	condition := Condition("[STATUS] == 200")
+	bodyCondition := Condition("[BODY].status == UP")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
-		Conditions: []*Condition{&condition},
+		Conditions: []*Condition{&condition, &bodyCondition},
 	}
 	result := service.EvaluateHealth()
 	if !result.ConditionResults[0].Success {
@@ -232,7 +233,7 @@ func TestIntegrationEvaluateHealth(t *testing.T) {
 func TestIntegrationEvaluateHealthWithFailure(t *testing.T) {
 	condition := Condition("[STATUS] == 500")
 	service := Service{
-		Name:       "TwiNNatioN",
+		Name:       "twinnation-health",
 		URL:        "https://twinnation.org/health",
 		Conditions: []*Condition{&condition},
 	}
@@ -252,7 +253,7 @@ func TestIntegrationEvaluateHealthForDNS(t *testing.T) {
 	conditionSuccess := Condition("[DNS_RCODE] == NOERROR")
 	conditionBody := Condition("[BODY] == 93.184.216.34")
 	service := Service{
-		Name: "TwiNNatioN",
+		Name: "example",
 		URL:  "8.8.8.8",
 		DNS: &DNS{
 			QueryType: "A",
@@ -275,7 +276,7 @@ func TestIntegrationEvaluateHealthForDNS(t *testing.T) {
 func TestIntegrationEvaluateHealthForICMP(t *testing.T) {
 	conditionSuccess := Condition("[CONNECTED] == true")
 	service := Service{
-		Name:       "ICMP test",
+		Name:       "icmp-test",
 		URL:        "icmp://127.0.0.1",
 		Conditions: []*Condition{&conditionSuccess},
 	}
@@ -294,7 +295,7 @@ func TestIntegrationEvaluateHealthForICMP(t *testing.T) {
 func TestService_getIP(t *testing.T) {
 	conditionSuccess := Condition("[CONNECTED] == true")
 	service := Service{
-		Name:       "Invalid URL test",
+		Name:       "invalid-url-test",
 		URL:        "",
 		Conditions: []*Condition{&conditionSuccess},
 	}
@@ -304,3 +305,27 @@ func TestService_getIP(t *testing.T) {
 		t.Error("service.getIP(result) should've thrown an error because the URL is invalid, thus cannot be parsed")
 	}
 }
+
+func TestService_NeedsToReadBody(t *testing.T) {
+	statusCondition := Condition("[STATUS] == 200")
+	bodyCondition := Condition("[BODY].status == UP")
+	bodyConditionWithLength := Condition("len([BODY].tags) > 0")
+	if (&Service{Conditions: []*Condition{&statusCondition}}).needsToReadBody() {
+		t.Error("expected false, got true")
+	}
+	if !(&Service{Conditions: []*Condition{&bodyCondition}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+	if !(&Service{Conditions: []*Condition{&bodyConditionWithLength}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+	if !(&Service{Conditions: []*Condition{&statusCondition, &bodyCondition}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+	if !(&Service{Conditions: []*Condition{&bodyCondition, &statusCondition}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+	if !(&Service{Conditions: []*Condition{&bodyConditionWithLength, &statusCondition}}).needsToReadBody() {
+		t.Error("expected true, got false")
+	}
+}

core/uptime.go

@@ -1,15 +1,10 @@
 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
 )
@@ -25,47 +20,45 @@ type Uptime struct {
 	// 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
+	// SuccessfulExecutionsPerHour is a map containing the number of successes (value)
-	// custom RFC3339WithoutMinutesAndSeconds format
+	// for every hourly unix timestamps (key)
-	SuccessCountPerHour map[string]uint64 `json:"-"`
+	SuccessfulExecutionsPerHour map[int64]uint64 `json:"-"`
 
-	// TotalCountPerHour is a map containing the total number of checks per hour, per timestamp following the
+	// TotalExecutionsPerHour is a map containing the total number of checks (value)
-	// custom RFC3339WithoutMinutesAndSeconds format
+	// for every hourly unix timestamps (key)
-	TotalCountPerHour map[string]uint64 `json:"-"`
+	TotalExecutionsPerHour map[int64]uint64 `json:"-"`
 }
 
 // NewUptime creates a new Uptime
 func NewUptime() *Uptime {
 	return &Uptime{
-		SuccessCountPerHour: make(map[string]uint64),
+		SuccessfulExecutionsPerHour: make(map[int64]uint64),
-		TotalCountPerHour:   make(map[string]uint64),
+		TotalExecutionsPerHour:      make(map[int64]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 uptime.SuccessfulExecutionsPerHour == nil || uptime.TotalExecutionsPerHour == nil {
-	if result.Success {
+		uptime.SuccessfulExecutionsPerHour = make(map[int64]uint64)
-		uptime.SuccessCountPerHour[timestampDateWithHour]++
+		uptime.TotalExecutionsPerHour = make(map[int64]uint64)
 	}
-	uptime.TotalCountPerHour[timestampDateWithHour]++
+	unixTimestampFlooredAtHour := result.Timestamp.Unix() - (result.Timestamp.Unix() % 3600)
+	if result.Success {
+		uptime.SuccessfulExecutionsPerHour[unixTimestampFlooredAtHour]++
+	}
+	uptime.TotalExecutionsPerHour[unixTimestampFlooredAtHour]++
 	// 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 {
+	if len(uptime.TotalExecutionsPerHour) > numberOfHoursInTenDays {
-		sevenDaysAgo := time.Now().Add(-(sevenDays + time.Hour))
+		sevenDaysAgo := time.Now().Add(-(sevenDays + time.Hour)).Unix()
-		for k := range uptime.TotalCountPerHour {
+		for hourlyUnixTimestamp := range uptime.TotalExecutionsPerHour {
-			dateWithHour, err := time.Parse(time.RFC3339, k)
+			if sevenDaysAgo > hourlyUnixTimestamp {
-			if err != nil {
+				delete(uptime.TotalExecutionsPerHour, hourlyUnixTimestamp)
-				// This shouldn't happen, but we'll log it in case it does happen
+				delete(uptime.SuccessfulExecutionsPerHour, hourlyUnixTimestamp)
-				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)
 			}
 		}
 	}
@@ -92,9 +85,9 @@ func (uptime *Uptime) recalculate() {
 	// 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)
+		hourlyUnixTimestamp := timestamp.Unix() - (timestamp.Unix() % 3600)
-		successCountForTimestamp := uptime.SuccessCountPerHour[timestampDateWithHour]
+		successCountForTimestamp := uptime.SuccessfulExecutionsPerHour[hourlyUnixTimestamp]
-		totalCountForTimestamp := uptime.TotalCountPerHour[timestampDateWithHour]
+		totalCountForTimestamp := uptime.TotalExecutionsPerHour[hourlyUnixTimestamp]
 		uptimeBrackets["7d_success"] += successCountForTimestamp
 		uptimeBrackets["7d_total"] += totalCountForTimestamp
 		if now.Sub(timestamp) <= 24*time.Hour {

core/uptime_test.go

@@ -51,10 +51,9 @@ func TestServiceStatus_AddResultUptimeIsCleaningUpAfterItself(t *testing.T) {
 	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 {
+		if len(serviceStatus.Uptime.SuccessfulExecutionsPerHour) > numberOfHoursInTenDays {
-			t.Errorf("At no point in time should there be more than %d entries in serviceStatus.SuccessCountPerHour", numberOfHoursInTenDays)
+			t.Errorf("At no point in time should there be more than %d entries in serviceStatus.SuccessfulExecutionsPerHour, but there are %d", numberOfHoursInTenDays, len(serviceStatus.Uptime.SuccessfulExecutionsPerHour))
 		}
-		//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)
 		}

jsonpath/jsonpath_test.go

@@ -20,6 +20,15 @@ func TestEval(t *testing.T) {
 	}
 }
 
+func TestEvalWithInvalidPath(t *testing.T) {
+	path := "errors"
+	data := `{}`
+	_, _, err := Eval(path, []byte(data))
+	if err == nil {
+		t.Error("Expected error, but got", err)
+	}
+}
+
 func TestEvalWithLongSimpleWalk(t *testing.T) {
 	path := "long.simple.walk"
 	data := `{"long": {"simple": {"walk": "value"}}}`

storage/store/memory/memory.go

@@ -58,7 +58,7 @@ func (s *Store) GetServiceStatusByKey(key string) *core.ServiceStatus {
 	if serviceStatus == nil {
 		return nil
 	}
-	return serviceStatus.(*core.ServiceStatus).ShallowCopy()
+	return serviceStatus.(*core.ServiceStatus)
 }
 
 // Insert adds the observed result for the specified service into the store

storage/store/memory/memory_test.go

@@ -33,7 +33,6 @@ var (
 		Hostname:              "example.org",
 		IP:                    "127.0.0.1",
 		HTTPStatus:            200,
-		Body:                  []byte("body"),
 		Errors:                nil,
 		Connected:             true,
 		Success:               true,
@@ -59,7 +58,6 @@ var (
 		Hostname:              "example.org",
 		IP:                    "127.0.0.1",
 		HTTPStatus:            200,
-		Body:                  []byte("body"),
 		Errors:                []string{"error-1", "error-2"},
 		Connected:             true,
 		Success:               false,
@@ -107,9 +105,6 @@ func TestStore_Insert(t *testing.T) {
 		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)
 		}

storage/store/store_bench_test.go

@@ -32,7 +32,6 @@ var (
 		Hostname:              "example.org",
 		IP:                    "127.0.0.1",
 		HTTPStatus:            200,
-		Body:                  []byte("body"),
 		Errors:                nil,
 		Connected:             true,
 		Success:               true,
@@ -58,7 +57,6 @@ var (
 		Hostname:              "example.org",
 		IP:                    "127.0.0.1",
 		HTTPStatus:            200,
-		Body:                  []byte("body"),
 		Errors:                []string{"error-1", "error-2"},
 		Connected:             true,
 		Success:               false,
@@ -127,8 +125,11 @@ func BenchmarkStore_Insert(b *testing.B) {
 	for _, scenario := range scenarios {
 		b.Run(scenario.Name, func(b *testing.B) {
 			for n := 0; n < b.N; n++ {
-				scenario.Store.Insert(&testService, &testSuccessfulResult)
+				if n%100 == 0 {
-				scenario.Store.Insert(&testService, &testUnsuccessfulResult)
+					scenario.Store.Insert(&testService, &testSuccessfulResult)
+				} else {
+					scenario.Store.Insert(&testService, &testUnsuccessfulResult)
+				}
 			}
 			b.ReportAllocs()
 		})

watchdog/watchdog.go

@@ -1,7 +1,6 @@
 package watchdog
 
 import (
-	"fmt"
 	"log"
 	"sync"
 	"time"
@@ -37,26 +36,22 @@ func monitor(service *core.Service) {
 			monitoringMutex.Lock()
 		}
 		if cfg.Debug {
-			log.Printf("[watchdog][monitor] Monitoring serviceName=%s", service.Name)
+			log.Printf("[watchdog][monitor] Monitoring group=%s; service=%s", service.Group, service.Name)
 		}
 		result := service.EvaluateHealth()
 		metric.PublishMetricsForService(service, result)
 		UpdateServiceStatuses(service, result)
-		var extra string
-		if !result.Success {
-			extra = fmt.Sprintf("responseBody=%s", result.Body)
-		}
 		log.Printf(
-			"[watchdog][monitor] Monitored serviceName=%s; success=%v; errors=%d; requestDuration=%s; %s",
+			"[watchdog][monitor] Monitored group=%s; service=%s; success=%v; errors=%d; duration=%s",
+			service.Group,
 			service.Name,
 			result.Success,
 			len(result.Errors),
 			result.Duration.Round(time.Millisecond),
-			extra,
 		)
 		HandleAlerting(service, result)
 		if cfg.Debug {
-			log.Printf("[watchdog][monitor] Waiting for interval=%s before monitoring serviceName=%s again", service.Interval, service.Name)
+			log.Printf("[watchdog][monitor] Waiting for interval=%s before monitoring group=%s service=%s again", service.Interval, service.Group, service.Name)
 		}
 		if !cfg.DisableMonitoringLock {
 			monitoringMutex.Unlock()