improve cluster handling via struct and add --all flag to commands

config.go

@@ -12,6 +12,12 @@ import (
 	"github.com/olekukonko/tablewriter"
 )
 
+type cluster struct {
+	name   string
+	image  string
+	status string
+}
+
 // createDirIfNotExists checks for the existence of a directory and creates it along with all required parents if not.
 // It returns an error if the directory (or parents) couldn't be created and nil if it worked fine or if the path already exists.
 func createDirIfNotExists(path string) error {
@@ -50,30 +56,30 @@ func getClusterDir(name string) (string, error) {
 
 // printClusters prints the names of existing clusters
 func printClusters(all bool) {
-	clusters, err := getClusters()
+	clusterNames, err := getClusterNames()
 	if err != nil {
 		log.Fatalf("ERROR: Couldn't list clusters -> %+v", err)
 	}
-	docker, err := dockerClient.NewEnvClient()
-	if err != nil {
-		log.Printf("WARNING: couldn't get docker info -> %+v", err)
+	if len(clusterNames) == 0 {
+		log.Printf("No clusters found!")
+		return
 	}
 
 	table := tablewriter.NewWriter(os.Stdout)
 	table.SetHeader([]string{"NAME", "IMAGE", "STATUS"})
 
-	for _, cluster := range clusters {
-		containerInfo, _ := docker.ContainerInspect(context.Background(), cluster)
-		clusterData := []string{cluster, containerInfo.Config.Image, containerInfo.ContainerJSONBase.State.Status}
-		if containerInfo.ContainerJSONBase.State.Status == "running" || all {
+	for _, clusterName := range clusterNames {
+		cluster, _ := getCluster(clusterName)
+		clusterData := []string{cluster.name, cluster.image, cluster.status}
+		if cluster.status == "running" || all {
 			table.Append(clusterData)
 		}
 	}
 	table.Render()
 }
 
-// getClusters returns a list of cluster names which are folder names in the config directory
-func getClusters() ([]string, error) {
+// getClusterNames returns a list of cluster names which are folder names in the config directory
+func getClusterNames() ([]string, error) {
 	homeDir, err := homedir.Dir()
 	if err != nil {
 		log.Printf("ERROR: Couldn't get user's home directory")
@@ -93,3 +99,26 @@ func getClusters() ([]string, error) {
 	}
 	return clusters, nil
 }
+
+// getCluster creates a cluster struct with populated information fields
+func getCluster(name string) (cluster, error) {
+	cluster := cluster{
+		name:   name,
+		image:  "UNKNOWN",
+		status: "UNKNOWN",
+	}
+
+	docker, err := dockerClient.NewEnvClient()
+	if err != nil {
+		log.Printf("ERROR: couldn't create docker client -> %+v", err)
+		return cluster, err
+	}
+	containerInfo, err := docker.ContainerInspect(context.Background(), cluster.name)
+	if err != nil {
+		log.Printf("WARNING: couldn't get docker info for [%s] -> %+v", cluster.name, err)
+	} else {
+		cluster.image = containerInfo.Config.Image
+		cluster.status = containerInfo.ContainerJSONBase.State.Status
+	}
+	return cluster, nil
+}

main.go

@@ -52,44 +52,104 @@ kubectl cluster-info`, os.Args[0], c.String("name"))
 // deleteCluster removes the cluster container and its cluster directory
 func deleteCluster(c *cli.Context) error {
 	cmd := "docker"
-	args := []string{"rm", c.String("name")}
-	log.Printf("Deleting cluster [%s]", c.String("name"))
-	if err := run(true, cmd, args...); err != nil {
-		log.Printf("WARNING: couldn't delete cluster [%s], trying a force remove now.", c.String("name"))
-		args = append(args, "-f")
+	args := []string{"rm"}
+	clusters := []string{}
+
+	// operate on one or all clusters
+	if !c.Bool("all") {
+		clusters = append(clusters, c.String("name"))
+	} else {
+		clusterList, err := getClusterNames()
+		if err != nil {
+			log.Fatalf("ERROR: `--all` specified, but no clusters were found.")
+		}
+		clusters = append(clusters, clusterList...)
+	}
+
+	// remove clusters one by one instead of appending all names to the docker command
+	// this allows for more granular error handling and logging
+	for _, cluster := range clusters {
+		log.Printf("Removing cluster [%s]", cluster)
+		args = append(args, cluster)
 		if err := run(true, cmd, args...); err != nil {
-			log.Fatalf("FAILURE: couldn't delete cluster [%s] -> %+v", c.String("name"), err)
-			return err
+			log.Printf("WARNING: couldn't delete cluster [%s], trying a force remove now.", cluster)
+			args = args[:len(args)-1] // pop last element from list (name of cluster)
+			args = append(args, "-f", cluster)
+			if err := run(true, cmd, args...); err != nil {
+				log.Printf("FAILURE: couldn't delete cluster [%s] -> %+v", cluster, err)
+			}
+			args = args[:len(args)-1] // pop last element from list (-f flag)
 		}
+		deleteClusterDir(cluster)
+		log.Printf("SUCCESS: removed cluster [%s]", cluster)
+		args = args[:len(args)-1] // pop last element from list (name of last cluster)
 	}
-	deleteClusterDir(c.String("name"))
-	log.Printf("SUCCESS: deleted cluster [%s]", c.String("name"))
+
 	return nil
+
 }
 
 // stopCluster stops a running cluster container (restartable)
 func stopCluster(c *cli.Context) error {
 	cmd := "docker"
-	args := []string{"stop", c.String("name")}
-	log.Printf("Stopping cluster [%s]", c.String("name"))
-	if err := run(true, cmd, args...); err != nil {
-		log.Fatalf("FAILURE: couldn't stop cluster [%s] -> %+v", c.String("name"), err)
-		return err
+	args := []string{"stop"}
+	clusters := []string{}
+
+	// operate on one or all clusters
+	if !c.Bool("all") {
+		clusters = append(clusters, c.String("name"))
+	} else {
+		clusterList, err := getClusterNames()
+		if err != nil {
+			log.Fatalf("ERROR: `--all` specified, but no clusters were found.")
+		}
+		clusters = append(clusters, clusterList...)
 	}
-	log.Printf("SUCCESS: stopped cluster [%s]", c.String("name"))
+
+	// stop clusters one by one instead of appending all names to the docker command
+	// this allows for more granular error handling and logging
+	for _, cluster := range clusters {
+		log.Printf("Starting cluster [%s]", cluster)
+		args = append(args, cluster)
+		if err := run(true, cmd, args...); err != nil {
+			log.Printf("FAILURE: couldn't stop cluster [%s] -> %+v", cluster, err)
+		}
+		log.Printf("SUCCESS: stopped cluster [%s]", cluster)
+		args = args[:len(args)-1] // pop last element from list (name of last cluster)
+	}
+
 	return nil
 }
 
 // startCluster starts a stopped cluster container
 func startCluster(c *cli.Context) error {
 	cmd := "docker"
-	args := []string{"start", c.String("name")}
-	log.Printf("Starting cluster [%s]", c.String("name"))
-	if err := run(true, cmd, args...); err != nil {
-		log.Fatalf("FAILURE: couldn't start cluster [%s] -> %+v", c.String("name"), err)
-		return err
+	args := []string{"start"}
+	clusters := []string{}
+
+	// operate on one or all clusters
+	if !c.Bool("all") {
+		clusters = append(clusters, c.String("name"))
+	} else {
+		clusterList, err := getClusterNames()
+		if err != nil {
+			log.Fatalf("ERROR: `--all` specified, but no clusters were found.")
+		}
+		clusters = append(clusters, clusterList...)
+	}
+
+	// start clusters one by one instead of appending all names to the docker command
+	// this allows for more granular error handling and logging
+	for _, cluster := range clusters {
+		log.Printf("Starting cluster [%s]", cluster)
+		args = append(args, cluster)
+		if err := run(true, cmd, args...); err != nil {
+			log.Printf("FAILURE: couldn't start cluster [%s] -> %+v", cluster, err)
+		}
+		log.Printf("SUCCESS: started cluster [%s]", cluster)
+		args = args[:len(args)-1] // pop last element from list (name of last cluster)
 	}
-	log.Printf("SUCCESS: started cluster [%s]", c.String("name"))
+
 	return nil
 }