enhancement: Provide new "run" and "version" commands to the CLI (#14)

* enhancement: Provide new "run" and "version" commands to the CLI

* Also update new usage in the docs

* Also update manifests

5 files changed, 64 insertions, 28 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 208d812..ccd63c5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,12 +8,17 @@ handling on your side.
 
 ### Upgrade notes (no really, you MUST read this)
 
+* Syntax change for running: `argocd-image-updater run [flags]` instead of `argocd-image-updater [flags]` has now to be used
+
 ### Bug fixes
 
 ### New features
 
 ### Other changes
 
+* refactor: Change run behaviour by providing `run` and `version` commands
+* enhancement: Provide a `version` command to print out version information
+
 ## 2020-08-06 - Release v0.2.0
 
 ### Upgrade notes (no really, you MUST read this)
diff --git a/cmd/main.go b/cmd/main.go
index dd25813..45ddf42 100644
--- a/cmd/main.go
+++ b/cmd/main.go
@@ -252,14 +252,41 @@ func getPrintableHealthPort(port int) string {
 	}
 }
 
-func newCommand() error {
+// newRootCommand implements the root command of argocd-image-updater
+func newRootCommand() error {
+	var rootCmd = &cobra.Command{
+		Use:   "argocd-image-updater",
+		Short: "Automatically update container images with ArgoCD",
+	}
+	rootCmd.AddCommand(newRunCommand())
+	rootCmd.AddCommand(newVersionCommand())
+	err := rootCmd.Execute()
+	return err
+}
+
+// newVersionCommand implements "version" command
+func newVersionCommand() *cobra.Command {
+	var versionCmd = &cobra.Command{
+		Use:   "version",
+		Short: "Display version information",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			fmt.Printf("%s\n", version.Useragent())
+			return nil
+		},
+	}
+
+	return versionCmd
+}
+
+// newRunCommand implements "run" command
+func newRunCommand() *cobra.Command {
 	var cfg *ImageUpdaterConfig = &ImageUpdaterConfig{}
 	var once bool
 	var kubeConfig string
 	var disableKubernetes bool
-	var rootCmd = &cobra.Command{
-		Use:   "argocd-image-updater",
-		Short: "Automatically update container images with ArgoCD",
+	var runCmd = &cobra.Command{
+		Use:   "run",
+		Short: "Runs the argocd-image-updater with a set of options",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			if err := log.SetLogLevel(cfg.LogLevel); err != nil {
 				return err
@@ -391,29 +418,27 @@ func newCommand() error {
 		},
 	}
 
-	rootCmd.Flags().StringVar(&cfg.ClientOpts.ServerAddr, "argocd-server-addr", getServerAddrFromEnv(), "address of ArgoCD API server")
-	rootCmd.Flags().BoolVar(&cfg.ClientOpts.GRPCWeb, "argocd-grpc-web", getBoolValFromEnv("ARGOCD_GRPC_WEB", false), "use grpc-web for connection to ArgoCD")
-	rootCmd.Flags().BoolVar(&cfg.ClientOpts.Insecure, "argocd-insecure", getBoolValFromEnv("ARGOCD_INSECURE", false), "(INSECURE) ignore invalid TLS certs for ArgoCD server")
-	rootCmd.Flags().BoolVar(&cfg.ClientOpts.Plaintext, "argocd-plaintext", getBoolValFromEnv("ARGOCD_PLAINTEXT", false), "(INSECURE) connect without TLS to ArgoCD server")
-	rootCmd.Flags().StringVar(&cfg.ClientOpts.AuthToken, "argocd-auth-token", "", "use token for authenticating to ArgoCD (unsafe - consider setting ARGOCD_TOKEN env var instead)")
-	rootCmd.Flags().BoolVar(&cfg.DryRun, "dry-run", false, "run in dry-run mode. If set to true, do not perform any changes")
-	rootCmd.Flags().DurationVar(&cfg.CheckInterval, "interval", 2*time.Minute, "interval for how often to check for updates")
-	rootCmd.Flags().StringVar(&cfg.LogLevel, "loglevel", "info", "set the loglevel to one of trace|debug|info|warn|error")
-	rootCmd.Flags().StringVar(&kubeConfig, "kubeconfig", "", "full path to kubernetes client configuration, i.e. ~/.kube/config")
-	rootCmd.Flags().IntVar(&cfg.HealthPort, "health-port", 8080, "port to start the health server on, 0 to disable")
-	rootCmd.Flags().BoolVar(&once, "once", false, "run only once, same as specifying --interval=0 and --healt-port=0")
-	rootCmd.Flags().StringVar(&cfg.RegistriesConf, "registries-conf-path", "", "path to registries configuration file")
-	rootCmd.Flags().BoolVar(&disableKubernetes, "disable-kubernetes", false, "do not create and use a Kubernetes client")
-
-	rootCmd.Flags().IntVar(&cfg.MaxConcurrency, "max-concurrency", 10, "maximum number of update threads to run concurrently")
-	rootCmd.Flags().StringVar(&cfg.ArgocdNamespace, "argocd-namespace", "argocd", "namespace where ArgoCD runs in")
-
-	err := rootCmd.Execute()
-	return err
+	runCmd.Flags().StringVar(&cfg.ClientOpts.ServerAddr, "argocd-server-addr", getServerAddrFromEnv(), "address of ArgoCD API server")
+	runCmd.Flags().BoolVar(&cfg.ClientOpts.GRPCWeb, "argocd-grpc-web", getBoolValFromEnv("ARGOCD_GRPC_WEB", false), "use grpc-web for connection to ArgoCD")
+	runCmd.Flags().BoolVar(&cfg.ClientOpts.Insecure, "argocd-insecure", getBoolValFromEnv("ARGOCD_INSECURE", false), "(INSECURE) ignore invalid TLS certs for ArgoCD server")
+	runCmd.Flags().BoolVar(&cfg.ClientOpts.Plaintext, "argocd-plaintext", getBoolValFromEnv("ARGOCD_PLAINTEXT", false), "(INSECURE) connect without TLS to ArgoCD server")
+	runCmd.Flags().StringVar(&cfg.ClientOpts.AuthToken, "argocd-auth-token", "", "use token for authenticating to ArgoCD (unsafe - consider setting ARGOCD_TOKEN env var instead)")
+	runCmd.Flags().BoolVar(&cfg.DryRun, "dry-run", false, "run in dry-run mode. If set to true, do not perform any changes")
+	runCmd.Flags().DurationVar(&cfg.CheckInterval, "interval", 2*time.Minute, "interval for how often to check for updates")
+	runCmd.Flags().StringVar(&cfg.LogLevel, "loglevel", "info", "set the loglevel to one of trace|debug|info|warn|error")
+	runCmd.Flags().StringVar(&kubeConfig, "kubeconfig", "", "full path to kubernetes client configuration, i.e. ~/.kube/config")
+	runCmd.Flags().IntVar(&cfg.HealthPort, "health-port", 8080, "port to start the health server on, 0 to disable")
+	runCmd.Flags().BoolVar(&once, "once", false, "run only once, same as specifying --interval=0 and --healt-port=0")
+	runCmd.Flags().StringVar(&cfg.RegistriesConf, "registries-conf-path", "", "path to registries configuration file")
+	runCmd.Flags().BoolVar(&disableKubernetes, "disable-kubernetes", false, "do not create and use a Kubernetes client")
+	runCmd.Flags().IntVar(&cfg.MaxConcurrency, "max-concurrency", 10, "maximum number of update threads to run concurrently")
+	runCmd.Flags().StringVar(&cfg.ArgocdNamespace, "argocd-namespace", "argocd", "namespace where ArgoCD runs in")
+
+	return runCmd
 }
 
 func main() {
-	err := newCommand()
+	err := newRootCommand()
 	if err != nil {
 		os.Exit(1)
 	}
diff --git a/docs/install/start.md b/docs/install/start.md
index 3033183..5fccbce 100644
--- a/docs/install/start.md
+++ b/docs/install/start.md
@@ -160,7 +160,7 @@ Grab the binary (it does not have any external dependencies) and run:
 
 ```bash
 export ARGOCD_TOKEN=<yourtoken>
-./argocd-image-updater \
+./argocd-image-updater run \
   --kubeconfig ~/.kube/config
   --argocd-server-addr argo-cd.example.com
   --once
diff --git a/manifests/base/deployment/argocd-image-updater-deployment.yaml b/manifests/base/deployment/argocd-image-updater-deployment.yaml
index 9d81dd9..92e1063 100644
--- a/manifests/base/deployment/argocd-image-updater-deployment.yaml
+++ b/manifests/base/deployment/argocd-image-updater-deployment.yaml
@@ -16,7 +16,10 @@ spec:
         app.kubernetes.io/name: argocd-image-updater
     spec:
       containers:
-      - image: argoproj-labs/argocd-image-updater:latest
+      - command:
+        - /usr/local/bin/argocd-image-updater
+        - run
+        image: argoproj-labs/argocd-image-updater:latest
         imagePullPolicy: Always
         env:
         - name: ARGOCD_GRPC_WEB
@@ -74,4 +77,4 @@ spec:
           name: argocd-image-updater-config
           items:
           - key: registries.conf
-            path: registries.conf
\ No newline at end of file
+            path: registries.conf
diff --git a/manifests/install.yaml b/manifests/install.yaml
index 8fdbeb2..772b438 100644
--- a/manifests/install.yaml
+++ b/manifests/install.yaml
@@ -41,7 +41,10 @@ spec:
         app.kubernetes.io/name: argocd-image-updater
     spec:
       containers:
-      - env:
+      - command:
+        - /usr/local/bin/argocd-image-updater
+        - run
+        env:
         - name: ARGOCD_GRPC_WEB
           valueFrom:
             configMapKeyRef: