refactor: Make --context cli flag a global option (#174)

* Make `--context` flag a global option and remove duplication

* Remove unused dns showOptions struct

* First pass of refactoring "active context" determination and validation

* Undo some refactoring in cli.go to keep diff more focused

cmd/uncloud/service/exec.go

@@ -15,7 +15,6 @@ type execCliOptions struct {
 	detach      bool
 	interactive bool
 	noTty       bool
-	context     string
 	containerId string
 }
 
@@ -69,9 +68,6 @@ If the service has multiple replicas and no container ID is specified, the comma
 	execCmd.Flags().BoolP("tty", "t", false, "Allocate a pseudo-TTY")
 	execCmd.Flags().MarkHidden("tty")
 
-	execCmd.Flags().StringVarP(&opts.context, "context", "c", "",
-		"Name of the cluster context. (default is the current context)")
-
 	// Common flags
 	execCmd.Flags().StringVar(&opts.containerId, "container", "",
 		"ID of the container to exec into. Accepts full ID or a unique prefix "+
@@ -95,7 +91,7 @@ func runExec(ctx context.Context, uncli *cli.CLI, serviceName string, command []
 		}
 	}
 
-	client, err := uncli.ConnectClusterWithOptions(ctx, opts.context, cli.ConnectOptions{
+	client, err := uncli.ConnectClusterWithOptions(ctx, cli.ConnectOptions{
 		ShowProgress: false,
 	})
 	if err != nil {

cmd/uncloud/service/inspect.go

@@ -15,7 +15,6 @@ import (
 
 type inspectOptions struct {
 	service string
-	context string
 }
 
 func NewInspectCommand() *cobra.Command {
@@ -30,15 +29,11 @@ func NewInspectCommand() *cobra.Command {
 			return inspect(cmd.Context(), uncli, opts)
 		},
 	}
-	cmd.Flags().StringVarP(
-		&opts.context, "context", "c", "",
-		"Name of the cluster context. (default is the current context)",
-	)
 	return cmd
 }
 
 func inspect(ctx context.Context, uncli *cli.CLI, opts inspectOptions) error {
-	client, err := uncli.ConnectCluster(ctx, opts.context)
+	client, err := uncli.ConnectCluster(ctx)
 	if err != nil {
 		return fmt.Errorf("connect to cluster: %w", err)
 	}

cmd/uncloud/service/ls.go

@@ -12,25 +12,20 @@ import (
 )
 
 func NewListCommand() *cobra.Command {
-	var contextName string
 	cmd := &cobra.Command{
 		Use:     "ls",
 		Aliases: []string{"list"},
 		Short:   "List services.",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			uncli := cmd.Context().Value("cli").(*cli.CLI)
-			return list(cmd.Context(), uncli, contextName)
+			return list(cmd.Context(), uncli)
 		},
 	}
-	cmd.Flags().StringVarP(
-		&contextName, "context", "c", "",
-		"Name of the cluster context. (default is the current context)",
-	)
 	return cmd
 }
 
-func list(ctx context.Context, uncli *cli.CLI, contextName string) error {
-	client, err := uncli.ConnectCluster(ctx, contextName)
+func list(ctx context.Context, uncli *cli.CLI) error {
+	client, err := uncli.ConnectCluster(ctx)
 	if err != nil {
 		return fmt.Errorf("connect to cluster: %w", err)
 	}

cmd/uncloud/service/rm.go

@@ -11,7 +11,6 @@ import (
 
 type rmOptions struct {
 	services []string
-	context  string
 }
 
 func NewRmCommand() *cobra.Command {
@@ -27,15 +26,11 @@ func NewRmCommand() *cobra.Command {
 			return rm(cmd.Context(), uncli, opts)
 		},
 	}
-	cmd.Flags().StringVarP(
-		&opts.context, "context", "c", "",
-		"Name of the cluster context. (default is the current context)",
-	)
 	return cmd
 }
 
 func rm(ctx context.Context, uncli *cli.CLI, opts rmOptions) error {
-	client, err := uncli.ConnectCluster(ctx, opts.context)
+	client, err := uncli.ConnectCluster(ctx)
 	if err != nil {
 		return fmt.Errorf("connect to cluster: %w", err)
 	}

cmd/uncloud/service/run.go

@@ -34,8 +34,6 @@ type runOptions struct {
 	replicas          uint
 	user              string
 	volumes           []string
-
-	context string
 }
 
 func NewRunCommand() *cobra.Command {
@@ -112,11 +110,6 @@ func NewRunCommand() *cobra.Command {
 			"  -v /data/uploads:/app/uploads         	 Bind mount /data/uploads host directory to /app/uploads in container\n"+
 			"  -v /host/path:/container/path:ro 		 Bind mount a host directory or file as read-only")
 
-	cmd.Flags().StringVarP(
-		&opts.context, "context", "c", "",
-		"Name of the cluster context to run the service in. (default is the current context)",
-	)
-
 	return cmd
 }
 
@@ -126,7 +119,7 @@ func run(ctx context.Context, uncli *cli.CLI, opts runOptions) error {
 		return err
 	}
 
-	clusterClient, err := uncli.ConnectCluster(ctx, opts.context)
+	clusterClient, err := uncli.ConnectCluster(ctx)
 	if err != nil {
 		return fmt.Errorf("connect to cluster: %w", err)
 	}

cmd/uncloud/service/scale.go

@@ -15,7 +15,6 @@ import (
 type scaleOptions struct {
 	service  string
 	replicas uint
-	context  string
 }
 
 func NewScaleCommand() *cobra.Command {
@@ -39,11 +38,6 @@ func NewScaleCommand() *cobra.Command {
 		},
 	}
 
-	cmd.Flags().StringVarP(
-		&opts.context, "context", "c", "",
-		"Name of the cluster context. (default is the current context)",
-	)
-
 	return cmd
 }
 
@@ -57,7 +51,7 @@ func scale(ctx context.Context, uncli *cli.CLI, opts scaleOptions) error {
 		)
 	}
 
-	clusterClient, err := uncli.ConnectCluster(ctx, opts.context)
+	clusterClient, err := uncli.ConnectCluster(ctx)
 	if err != nil {
 		return fmt.Errorf("connect to cluster: %w", err)
 	}