Refactor airshipctl root command

As part of config refactoring process, we have to prepare root
level command to future changes, optimize function signatures
and its logic.

Change-Id: I563a7556ce1cca795a74cf2c6a26380467a15a5d
Signed-off-by: Ruslan Aliev <raliev@mirantis.com>
Relates-To: #327

cmd/root.go

@@ -34,15 +34,14 @@ import (
 )
 
 // NewAirshipCTLCommand creates a root `airshipctl` command with the default commands attached
-func NewAirshipCTLCommand(out io.Writer) (*cobra.Command, *environment.AirshipCTLSettings, error) {
+func NewAirshipCTLCommand(out io.Writer) *cobra.Command {
-	rootCmd, settings, err := NewRootCommand(out)
+	rootCmd, settings := NewRootCommand(out)
-	return AddDefaultAirshipCTLCommands(rootCmd, settings), settings, err
+	return AddDefaultAirshipCTLCommands(rootCmd, settings)
 }
 
 // NewRootCommand creates the root `airshipctl` command. All other commands are
 // subcommands branching from this one
-func NewRootCommand(out io.Writer) (*cobra.Command, *environment.AirshipCTLSettings, error) {
+func NewRootCommand(out io.Writer) (*cobra.Command, *environment.AirshipCTLSettings) {
-	settings := &environment.AirshipCTLSettings{}
 	rootCmd := &cobra.Command{
 		Use:           "airshipctl",
 		Short:         "A unified entrypoint to various airship components",
@@ -50,11 +49,8 @@ func NewRootCommand(out io.Writer) (*cobra.Command, *environment.AirshipCTLSetti
 		SilenceUsage:  true,
 	}
 	rootCmd.SetOut(out)
-	rootCmd.AddCommand(NewVersionCommand())
 
-	settings.InitFlags(rootCmd)
+	return rootCmd, makeRootSettings(rootCmd)
-
-	return rootCmd, settings, nil
 }
 
 // AddDefaultAirshipCTLCommands is a convenience function for adding all of the
@@ -68,6 +64,14 @@ func AddDefaultAirshipCTLCommands(cmd *cobra.Command, settings *environment.Airs
 	cmd.AddCommand(image.NewImageCommand(settings))
 	cmd.AddCommand(secret.NewSecretCommand())
 	cmd.AddCommand(phase.NewPhaseCommand(settings))
+	cmd.AddCommand(NewVersionCommand())
 
 	return cmd
 }
+
+// makeRootSettings holds all actions about environment.AirshipCTLSettings
+func makeRootSettings(cmd *cobra.Command) *environment.AirshipCTLSettings {
+	settings := &environment.AirshipCTLSettings{}
+	settings.InitFlags(cmd)
+	return settings
+}

cmd/root_test.go

@@ -75,11 +75,10 @@ func TestFlagLoading(t *testing.T) {
 		t.Run(tt.name, func(subTest *testing.T) {
 			// We don't care about the output of this test, so toss
 			// it into a throwaway &bytes.buffer{}
-			rootCmd, settings, err := cmd.NewRootCommand(&bytes.Buffer{})
+			rootCmd, settings := cmd.NewRootCommand(&bytes.Buffer{})
-			require.NoError(t, err)
 			rootCmd.SetArgs(tt.args)
 
-			err = rootCmd.Execute()
+			err := rootCmd.Execute()
 			require.NoError(t, err)
 
 			assert.Equal(t, settings.AirshipConfigPath, tt.expected)
@@ -89,15 +88,13 @@ func TestFlagLoading(t *testing.T) {
 
 func getVanillaRootCommand(t *testing.T) *cobra.Command {
 	t.Helper()
-	rootCmd, _, err := cmd.NewRootCommand(nil)
+	rootCmd, _ := cmd.NewRootCommand(nil)
-	require.NoError(t, err, "Could not create root commands")
 	return rootCmd
 }
 
 func getDefaultRootCommand(t *testing.T) *cobra.Command {
 	t.Helper()
-	rootCmd, _, err := cmd.NewAirshipCTLCommand(nil)
+	rootCmd := cmd.NewAirshipCTLCommand(nil)
-	require.NoError(t, err, "Could not create root commands")
 	return rootCmd
 }
 

cmd/testdata/TestRootGoldenOutput/rootCmd-with-no-subcommands.golden

@@ -1,16 +1,2 @@
 A unified entrypoint to various airship components
 
-Usage:
-  airshipctl [command]
-
-Available Commands:
-  help        Help about any command
-  version     Show the version number of airshipctl
-
-Flags:
-      --airshipconf string   Path to file for airshipctl configuration. (default "$HOME/.airship/config")
-      --debug                enable verbose output
-  -h, --help                 help for airshipctl
-      --kubeconfig string    Path to kubeconfig associated with airshipctl configuration. (default "$HOME/.airship/kubeconfig")
-
-Use "airshipctl [command] --help" for more information about a command.

cmd/testdata/TestRootGoldenOutput/specialized-rootCmd-with-bootstrap.golden

@@ -6,7 +6,6 @@ Usage:
 Available Commands:
   baremetal   Perform actions on baremetal hosts
   help        Help about any command
-  version     Show the version number of airshipctl
 
 Flags:
       --airshipconf string   Path to file for airshipctl configuration. (default "$HOME/.airship/config")

docs/tools/generate_cli_docs.go

@@ -24,11 +24,7 @@ import (
 )
 
 func main() {
-	rootCmd, _, err := cmd.NewAirshipCTLCommand(os.Stdout)
+	rootCmd := cmd.NewAirshipCTLCommand(os.Stdout)
-	if err != nil {
-		fmt.Fprintln(os.Stdout, err)
-		os.Exit(1)
-	}
 
 	// Remote auto-generated notice
 	rootCmd.DisableAutoGenTag = true

main.go

@@ -22,13 +22,7 @@ import (
 )
 
 func main() {
-	rootCmd, _, err := cmd.NewAirshipCTLCommand(os.Stdout)
+	if err := cmd.NewAirshipCTLCommand(os.Stdout).Execute(); err != nil {
-	if err != nil {
-		fmt.Fprintln(os.Stdout, err)
-		os.Exit(1)
-	}
-
-	if err := rootCmd.Execute(); err != nil {
 		fmt.Fprintln(os.Stderr, err)
 		os.Exit(1)
 	}