Merge M3 into MCS (#187)

* Merge M3 into MCS

* Fix Linting

* Add missing cluster folder

cluster/config.go

@@ -0,0 +1,168 @@
+// This file is part of MinIO Kubernetes Cloud
+// Copyright (c) 2019 MinIO, Inc.
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package cluster
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"net"
+	"net/http"
+	"regexp"
+	"strings"
+	"time"
+
+	"github.com/minio/minio/pkg/env"
+)
+
+var (
+	errCantDetermineMinIOImage = errors.New("can't determine MinIO Image")
+	errCantDetermineMCImage    = errors.New("can't determine MC Image")
+)
+
+func getK8sAPIServer() string {
+	// if m3 is running inside a k8s pod KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT will contain the k8s api server apiServerAddress
+	// if m3 is not running inside k8s by default will look for the k8s api server on localhost:8001 (kubectl proxy)
+	// NOTE: using kubectl proxy is for local development only, since every request send to localhost:8001 will bypass service account authentication
+	// more info here: https://kubernetes.io/docs/tasks/access-application-cluster/access-cluster/#directly-accessing-the-rest-api
+	// you can override this using M3_K8S_API_SERVER, ie use the k8s cluster from `kubectl config view`
+	host, port := env.Get("KUBERNETES_SERVICE_HOST", ""), env.Get("KUBERNETES_SERVICE_PORT", "")
+	apiServerAddress := "http://localhost:8001"
+	if host != "" && port != "" {
+		apiServerAddress = "https://" + net.JoinHostPort(host, port)
+	}
+	return env.Get(M3K8sAPIServer, apiServerAddress)
+}
+
+// getK8sAPIServerInsecure allow to tell the k8s client to skip TLS certificate verification, ie: when connecting to a k8s cluster
+// that uses certificate not trusted by your machine
+func getK8sAPIServerInsecure() bool {
+	return strings.ToLower(env.Get(m3k8SAPIServerInsecure, "off")) == "on"
+}
+
+// GetNsFromFile assumes mkube is running inside a k8s pod and extract the current namespace from the
+// /var/run/secrets/kubernetes.io/serviceaccount/namespace file
+func GetNsFromFile() string {
+	dat, err := ioutil.ReadFile("/var/run/secrets/kubernetes.io/serviceaccount/namespace")
+	if err != nil {
+		return "default"
+	}
+	return string(dat)
+}
+
+// This operation will run only once at mkube startup
+var namespace = GetNsFromFile()
+
+// Returns the namespace in which the controller is installed
+func GetNs() string {
+	return env.Get(M3Namespace, namespace)
+}
+
+// getLatestMinIOImage returns the latest docker image for MinIO if found on the internet
+func getLatestMinIOImage(client HTTPClientI) (*string, error) {
+	resp, err := client.Get("https://dl.min.io/server/minio/release/linux-amd64/")
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+	var re = regexp.MustCompile(`(?m)\.\/minio\.(RELEASE.*?Z)"`)
+	// look for a single match
+	matches := re.FindAllStringSubmatch(string(body), 1)
+	for i := range matches {
+		release := matches[i][1]
+		dockerImage := fmt.Sprintf("minio/minio:%s", release)
+		return &dockerImage, nil
+	}
+	return nil, errCantDetermineMinIOImage
+}
+
+var latestMinIOImage, errLatestMinIOImage = getLatestMinIOImage(
+	&HTTPClient{
+		Client: &http.Client{
+			Timeout: 4 * time.Second,
+		},
+	})
+
+// GetMinioImage returns the image URL to be used when deploying a MinIO instance, if there is
+// a preferred image to be used (configured via ENVIRONMENT VARIABLES) GetMinioImage will return that
+// if not, GetMinioImage will try to obtain the image URL for the latest version of MinIO and return that
+func GetMinioImage() (*string, error) {
+	image := strings.TrimSpace(env.Get(M3MinioImage, ""))
+	// if there is a preferred image configured by the user we'll always return that
+	if image != "" {
+		return &image, nil
+	}
+	if errLatestMinIOImage != nil {
+		return nil, errLatestMinIOImage
+	}
+	return latestMinIOImage, nil
+}
+
+// GetLatestMinioImage returns the latest image URL on minio repository
+func GetLatestMinioImage(client HTTPClientI) (*string, error) {
+	latestMinIOImage, err := getLatestMinIOImage(client)
+	if err != nil {
+		return nil, err
+	}
+	return latestMinIOImage, nil
+}
+
+// getLatestMCImage returns the latest docker image for MC if found on the internet
+func getLatestMCImage() (*string, error) {
+	// Create an http client with a 4 second timeout
+	client := http.Client{
+		Timeout: 4 * time.Second,
+	}
+	resp, err := client.Get("https://dl.min.io/client/mc/release/linux-amd64/")
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	body, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+	var re = regexp.MustCompile(`(?m)\.\/mc\.(RELEASE.*?Z)"`)
+	// look for a single match
+	matches := re.FindAllStringSubmatch(string(body), 1)
+	for i := range matches {
+		release := matches[i][1]
+		dockerImage := fmt.Sprintf("minio/mc:%s", release)
+		return &dockerImage, nil
+	}
+	return nil, errCantDetermineMCImage
+}
+
+var latestMCImage, errLatestMCImage = getLatestMCImage()
+
+func GetMCImage() (*string, error) {
+	image := strings.TrimSpace(env.Get(M3MCImage, ""))
+	// if there is a preferred image configured by the user we'll always return that
+	if image != "" {
+		return &image, nil
+	}
+	if errLatestMCImage != nil {
+		return nil, errLatestMCImage
+	}
+	return latestMCImage, nil
+}