Issue #37: Added multi-cluster support

Modified implementations and updated botkube help. Removed CheckChannel value from config and helm charts.

config.yaml

@@ -125,5 +125,3 @@ settings:
   clustername: not-configured
   # Set false to disable kubectl commands execution
   allowkubectl: false
-  # Set true only respond to channel in config
-  checkchannel: false

design/multi-cluster.md

@@ -40,7 +40,7 @@ To get the list of all clusters configured in the slack, you can run the followi
 
 ##### Workflow
 
-![alt text](https://raw.githubusercontent.com/mugdha-adhav/botkube/infracloudio/add-cluster-name/design/workflow.png)
+![Multi_Cluster_Design](https://raw.githubusercontent.com/infracloudio/botkube/infracloudio/add-cluster-name/design/workflow.png)
 
 
 ### Drawbacks

helm/botkube/values.yaml

@@ -140,8 +140,6 @@ config:
     clustername: not-configured
     # Set false to disable kubectl commands execution
     allowkubectl: false
-    # Set true only respond to channel in config
-    checkchannel: false
 
 resources: {}
   # We usually recommend not to specify default resources and to leave this as a conscious

pkg/config/config.go

@@ -49,7 +49,6 @@ type Slack struct {
 type Settings struct {
 	ClusterName  string
 	AllowKubectl bool
-	CheckChannel bool
 }
 
 // New returns new Config

pkg/execute/executor.go

@@ -26,10 +26,14 @@ var validKubectlCommands = map[string]bool{
 	"auth":          true,
 }
 
-var validNotifierCommands = map[string]bool{
+var validNotifierCommand = map[string]bool{
 	"notifier": true,
-	"help":     true,
-	"ping":     true,
+}
+var validPingCommand = map[string]bool{
+	"ping": true,
+}
+var validHelpCommand = map[string]bool{
+	"help": true,
 }
 
 var kubectlBinary = "/usr/local/bin/kubectl"
@@ -48,17 +52,52 @@ type Executor interface {
 
 // DefaultExecutor is a default implementations of Executor
 type DefaultExecutor struct {
-	Message      string
-	AllowKubectl bool
-	ClusterName  string
+	Message       string
+	AllowKubectl  bool
+	ClusterName   string
+	ChannelName   string
+	IsAuthChannel bool
+}
+
+// NotifierAction creates custom type for notifier actions
+type NotifierAction string
+
+// Defines constants for notifier actions
+const (
+	Start      NotifierAction = "start"
+	Stop       NotifierAction = "stop"
+	Status     NotifierAction = "status"
+	ShowConfig NotifierAction = "showconfig"
+)
+
+func (action NotifierAction) String() string {
+	return string(action)
+}
+
+// CommandFlags creates custom type for flags in botkube
+type CommandFlags string
+
+// Defines botkube flags
+const (
+	ClusterFlag    CommandFlags = "--cluster-name"
+	FollowFlag     CommandFlags = "--follow"
+	AbbrFollowFlag CommandFlags = "-f"
+	WatchFlag      CommandFlags = "--watch"
+	AbbrWatchFlag  CommandFlags = "-w"
+)
+
+func (flag CommandFlags) String() string {
+	return string(flag)
 }
 
 // NewDefaultExecutor returns new Executor object
-func NewDefaultExecutor(msg string, allowkubectl bool, clustername string) Executor {
+func NewDefaultExecutor(msg string, allowkubectl bool, clusterName, channelName string, isAuthChannel bool) Executor {
 	return &DefaultExecutor{
-		Message:      msg,
-		AllowKubectl: allowkubectl,
-		ClusterName:  clustername,
+		Message:       msg,
+		AllowKubectl:  allowkubectl,
+		ClusterName:   clusterName,
+		ChannelName:   channelName,
+		IsAuthChannel: isAuthChannel,
 	}
 }
 
@@ -69,35 +108,44 @@ func (e *DefaultExecutor) Execute() string {
 		if !e.AllowKubectl {
 			return fmt.Sprintf(kubectlDisabledMsg, e.ClusterName)
 		}
-		return fmt.Sprintf("Cluster: %s\n%s", e.ClusterName, runKubectlCommand(args))
+		return runKubectlCommand(args, e.ClusterName, e.IsAuthChannel)
 	}
-	if validNotifierCommands[args[0]] {
-		return runNotifierCommand(args, e.ClusterName)
+	if validNotifierCommand[args[0]] {
+		return runNotifierCommand(args, e.ClusterName, e.IsAuthChannel)
+	}
+	if validPingCommand[args[0]] {
+		return runPingCommand(args, e.ClusterName)
+	}
+	if validHelpCommand[args[0]] {
+		return printHelp(e.ChannelName)
 	}
 	return unsupportedCmdMsg
 }
 
-func printHelp() string {
+func printHelp(channelName string) string {
 	allowedKubectl := ""
 	for k := range validKubectlCommands {
 		allowedKubectl = allowedKubectl + k + ", "
 	}
 	helpMsg := "BotKube executes kubectl commands on k8s cluster and returns output.\n" +
 		"Usages:\n" +
-		"    @BotKube <kubectl command without `kubectl` prefix>\n" +
+		"    @BotKube <kubectl command without `kubectl` prefix> [" + ClusterFlag.String() + " <cluster_name>]\n" +
 		"e.g:\n" +
 		"    @BotKube get pods\n" +
 		"    @BotKube logs podname -n namespace\n" +
+		"    @BotKube get deployment " + ClusterFlag.String() + " cluster_name\n" +
 		"Allowed kubectl commands:\n" +
 		"    " + allowedKubectl + "\n\n" +
-		"Commands to manage notifier:\n" +
-		"notifier stop          Stop sending k8s event notifications to Slack (started by default)\n" +
-		"notifier start         Start sending k8s event notifications to Slack\n" +
-		"notifier status        Show running status of event notifier\n" +
-		"notifier showconfig    Show BotKube configuration for event notifier\n\n" +
+		"Commands to manage notifier (Runs only on configured channel " + channelName + "):\n" +
+		"@BotKube notifier stop          Stop sending k8s event notifications to Slack (started by default)\n" +
+		"@BotKube notifier start         Start sending k8s event notifications to Slack\n" +
+		"@BotKube notifier status        Show running status of event notifier\n" +
+		"@BotKube notifier showconfig    Show BotKube configuration for event notifier\n\n" +
 		"Other Commands:\n" +
-		"help                   Show help\n" +
-		"ping                   Check connection health\n"
+		"@BotKube help                   Show help\n" +
+		"@BotKube ping                   Check connection health\n\n" +
+		"Options:\n" +
+		"" + ClusterFlag.String() + "         Get cluster specific response\n"
 	return helpMsg
 
 }
@@ -106,71 +154,100 @@ func printDefaultMsg() string {
 	return unsupportedCmdMsg
 }
 
-func runKubectlCommand(args []string) string {
+func runKubectlCommand(args []string, clusterName string, isAuthChannel bool) string {
 	// Use 'default' as a default namespace
 	args = append([]string{"-n", "default"}, args...)
 
 	// Remove unnecessary flags
 	finalArgs := []string{}
-	for _, a := range args {
-		if a == "-f" || strings.HasPrefix(a, "--follow") {
+	checkFlag := false
+	for _, arg := range args {
+		if checkFlag {
+			if arg != clusterName {
+				return ""
+			}
+			checkFlag = false
 			continue
 		}
-		if a == "-w" || strings.HasPrefix(a, "--watch") {
+		if arg == AbbrFollowFlag.String() || strings.HasPrefix(arg, FollowFlag.String()) {
 			continue
 		}
-		finalArgs = append(finalArgs, a)
+		if arg == AbbrWatchFlag.String() || strings.HasPrefix(arg, WatchFlag.String()) {
+			continue
+		}
+		if strings.HasPrefix(arg, ClusterFlag.String()) {
+			if arg == ClusterFlag.String() {
+				checkFlag = true
+			} else if strings.SplitAfterN(arg, ClusterFlag.String()+"=", 2)[1] != clusterName {
+				return ""
+			}
+			isAuthChannel = true
+			continue
+		}
+		finalArgs = append(finalArgs, arg)
+	}
+	if isAuthChannel == false {
+		return ""
 	}
-
 	cmd := exec.Command(kubectlBinary, finalArgs...)
 	out, err := cmd.CombinedOutput()
 	if err != nil {
 		log.Logger.Error("Error in executing kubectl command: ", err)
-		return string(out) + err.Error()
+		return fmt.Sprintf("Cluster: %s\n%s", clusterName, string(out)+err.Error())
 	}
-	return string(out)
+	return fmt.Sprintf("Cluster: %s\n%s", clusterName, string(out))
 }
 
 // TODO: Have a seperate cli which runs bot commands
-func runNotifierCommand(args []string, clustername string) string {
-	switch len(args) {
-	case 1:
-		if strings.ToLower(args[0]) == "help" {
-			return printHelp()
-		}
-		if strings.ToLower(args[0]) == "ping" {
-			return fmt.Sprintf("pong from cluster '%s'", clustername)
-		}
-	case 2:
-		if args[0] != "notifier" {
-			return printDefaultMsg()
-		}
-		if args[1] == "start" {
-			config.Notify = true
-			log.Logger.Info("Notifier enabled")
-			return fmt.Sprintf(notifierStartMsg, clustername)
+func runNotifierCommand(args []string, clusterName string, isAuthChannel bool) string {
+	if isAuthChannel == false {
+		return ""
+	}
+	switch args[1] {
+	case Start.String():
+		config.Notify = true
+		log.Logger.Info("Notifier enabled")
+		return fmt.Sprintf(notifierStartMsg, clusterName)
+	case Stop.String():
+		config.Notify = false
+		log.Logger.Info("Notifier disabled")
+		return fmt.Sprintf(notifierStopMsg, clusterName)
+	case Status.String():
+		if config.Notify == false {
+			return fmt.Sprintf("Notifications are off for cluster '%s'", clusterName)
 		}
-		if args[1] == "stop" {
-			config.Notify = false
-			log.Logger.Info("Notifier disabled")
-			return fmt.Sprintf(notifierStopMsg, clustername)
+		return fmt.Sprintf("Notifications are on for cluster '%s'", clusterName)
+	case ShowConfig.String():
+		out, err := showControllerConfig()
+		if err != nil {
+			log.Logger.Error("Error in executing showconfig command: ", err)
+			return "Error in getting configuration!"
 		}
-		if args[1] == "status" {
-			if config.Notify == false {
-				return fmt.Sprintf("Notifications are off for cluster '%s'", clustername)
+		return fmt.Sprintf("Showing config for cluster '%s'\n\n%s", clusterName, out)
+	}
+	return printDefaultMsg()
+}
+
+func runPingCommand(args []string, clusterName string) string {
+	checkFlag := false
+	for _, arg := range args {
+		if checkFlag {
+			if arg != clusterName {
+				return ""
 			}
-			return fmt.Sprintf("Notifications are on for cluster '%s'", clustername)
+			checkFlag = false
+			continue
 		}
-		if args[1] == "showconfig" {
-			out, err := showControllerConfig()
-			if err != nil {
-				log.Logger.Error("Error in executing showconfig command: ", err)
-				return "Error in getting configuration!"
+		if strings.HasPrefix(arg, ClusterFlag.String()) {
+			if arg == ClusterFlag.String() {
+				checkFlag = true
+			} else if strings.SplitAfterN(arg, ClusterFlag.String()+"=", 2)[1] != clusterName {
+				return ""
 			}
-			return fmt.Sprintf("Showing config for cluster '%s'\n\n%s", clustername, out)
+			continue
 		}
 	}
-	return printDefaultMsg()
+	return fmt.Sprintf("pong from cluster '%s'", clusterName)
 }
 
 func showControllerConfig() (string, error) {

pkg/slack/slack.go

@@ -22,6 +22,7 @@ type Bot struct {
 type slackMessage struct {
 	ChannelID    string
 	BotID        string
+	MessageType  string
 	InMessage    string
 	OutMessage   string
 	OutMsgLength int
@@ -55,6 +56,7 @@ func (b *Bot) Start() {
 	go rtm.ManageConnection()
 
 	for msg := range rtm.IncomingEvents {
+		isAuthChannel := false
 		switch ev := msg.Data.(type) {
 		case *slack.ConnectedEvent:
 			logging.Logger.Debug("Connection Info: ", ev.Info)
@@ -73,10 +75,9 @@ func (b *Bot) Start() {
 					if !strings.HasPrefix(ev.Text, "<@"+botID+"> ") {
 						continue
 					}
-					// if config.settings.checkChannel is true
 					// Serve only if current channel is in config
-					if b.CheckChannel && (b.ChannelName != info.Name) {
-						continue
+					if b.ChannelName == info.Name {
+						isAuthChannel = true
 					}
 				}
 			}
@@ -95,7 +96,7 @@ func (b *Bot) Start() {
 				InMessage: inMessage,
 				RTM:       rtm,
 			}
-			sm.HandleMessage(b.AllowKubectl, b.ClusterName)
+			sm.HandleMessage(b.AllowKubectl, b.ClusterName, b.ChannelName, isAuthChannel)
 
 		case *slack.RTMError:
 			logging.Logger.Errorf("Slack RMT error: %+v", ev.Error())
@@ -108,8 +109,8 @@ func (b *Bot) Start() {
 	}
 }
 
-func (sm *slackMessage) HandleMessage(allowkubectl bool, clustername string) {
-	e := execute.NewDefaultExecutor(sm.InMessage, allowkubectl, clustername)
+func (sm *slackMessage) HandleMessage(allowkubectl bool, clusterName, channelName string, isAuthChannel bool) {
+	e := execute.NewDefaultExecutor(sm.InMessage, allowkubectl, clusterName, channelName, isAuthChannel)
 	sm.OutMessage = e.Execute()
 	sm.OutMsgLength = len(sm.OutMessage)
 	sm.Send()
@@ -141,7 +142,11 @@ func (sm slackMessage) Send() {
 			logging.Logger.Error("Error in uploading file:", err)
 		}
 		return
+	} else if sm.OutMsgLength == 0 {
+		logging.Logger.Info("Invalid request. Dumping the response")
+		return
 	}
+
 	params := slack.PostMessageParameters{
 		AsUser: true,
 	}