chore: delete command namespace (#1372)

* chore: delete command namespace

- Fixes bug where deleting by name fails if current path has no
  initialized function.
- Adds namespace test to delete command
- Moves namespace flag into delete command for
  - Better help text
  - Easier testing
- Sets static default namespace for flag to "default"

* fix comments/docs

* delete tests with nonexistent kubeconfig

* fix help text

cmd/delete.go

@@ -33,7 +33,7 @@ No local files are deleted.
 `,
 		SuggestFor:        []string{"remove", "rm", "del"},
 		ValidArgsFunction: CompleteFunctionList,
-		PreRunE:           bindEnv("path", "confirm", "all"),
+		PreRunE:           bindEnv("path", "confirm", "all", "namespace"),
 		SilenceUsage:      true, // no usage dump on error
 	}
 
@@ -45,7 +45,7 @@ No local files are deleted.
 
 	// Flags
 	cmd.Flags().BoolP("confirm", "c", cfg.Confirm, "Prompt to confirm all configuration options (Env: $FUNC_CONFIRM)")
-	cmd.Flags().StringP("namespace", "n", "", "The namespace in which to delete. (Env: $FUNC_NAMESPACE)")
+	cmd.Flags().StringP("namespace", "n", cfg.Namespace, "The namespace in which to delete. (Env: $FUNC_NAMESPACE)")
 	cmd.Flags().StringP("all", "a", "true", "Delete all resources created for a function, eg. Pipelines, Secrets, etc. (Env: $FUNC_ALL) (allowed values: \"true\", \"false\")")
 	setPathFlag(cmd)
 
@@ -59,7 +59,7 @@ No local files are deleted.
 }
 
 func runDelete(cmd *cobra.Command, args []string, newClient ClientFactory) (err error) {
-	config, err := newDeleteConfig(args).Prompt()
+	cfg, err := newDeleteConfig(args).Prompt()
 	if err != nil {
 		if err == terminal.InterruptErr {
 			return nil
@@ -79,28 +79,29 @@ func runDelete(cmd *cobra.Command, args []string, newClient ClientFactory) (err
 			Name: args[0],
 		}
 	} else {
-		function, err = fn.NewFunction(config.Path)
+		function, err = fn.NewFunction(cfg.Path)
 		if err != nil {
 			return
 		}
 
 		// Check if the function has been initialized
 		if !function.Initialized() {
-			return fmt.Errorf("the given path '%v' does not contain an initialized function", config.Path)
+			return fmt.Errorf("the given path '%v' does not contain an initialized function", cfg.Path)
+		}
+
+		// If not provided, use the function's extant namespace
+		if !cmd.Flags().Changed("namespace") {
+			cfg.Namespace = function.Deploy.Namespace
 		}
-	}
 
-	// If not provided, use the function's extant namespace
-	if config.Namespace == "" {
-		config.Namespace = function.Deploy.Namespace
 	}
 
 	// Create a client instance from the now-final config
-	client, done := newClient(ClientConfig{Namespace: config.Namespace, Verbose: config.Verbose})
+	client, done := newClient(ClientConfig{Namespace: cfg.Namespace, Verbose: cfg.Verbose})
 	defer done()
 
 	// Invoke remove using the concrete client impl
-	return client.Remove(cmd.Context(), function, config.DeleteAll)
+	return client.Remove(cmd.Context(), function, cfg.DeleteAll)
 }
 
 type deleteConfig struct {

cmd/delete_test.go

@@ -2,12 +2,69 @@ package cmd
 
 import (
 	"os"
+	"path/filepath"
 	"testing"
 
 	fn "knative.dev/func"
 	"knative.dev/func/mock"
 )
 
+// TestDelete_Namespace ensures that the namespace provided to the client
+// for use when deleting a function is set
+// 1. The flag /env variable if provided
+// 2. The namespace of the function at path if provided
+// 3. The user's current active namespace
+func TestDelete_Namespace(t *testing.T) {
+	root := fromTempDirectory(t)
+
+	// Ensure that the default is "default" when no context can be identified
+	t.Setenv("KUBECONFIG", filepath.Join(cwd(), "nonexistent"))
+	cmd := NewDeleteCmd(func(cc ClientConfig, options ...fn.Option) (*fn.Client, func()) {
+		if cc.Namespace != "default" {
+			t.Fatalf("expected 'default', got '%v'", cc.Namespace)
+		}
+		return fn.New(), func() {}
+	})
+	cmd.SetArgs([]string{"somefunc"}) // delete by name such that no f need be created
+	if err := cmd.Execute(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Ensure the extant function's namespace is used
+	f := fn.Function{
+		Root:    root,
+		Runtime: "go",
+		Deploy: fn.DeploySpec{
+			Namespace: "deployed",
+		},
+	}
+	if err := fn.New().Create(f); err != nil {
+		t.Fatal(err)
+	}
+	cmd = NewDeleteCmd(func(cc ClientConfig, options ...fn.Option) (*fn.Client, func()) {
+		if cc.Namespace != "deployed" {
+			t.Fatalf("expected 'deployed', got '%v'", cc.Namespace)
+		}
+		return fn.New(), func() {}
+	})
+	if err := cmd.Execute(); err != nil {
+		t.Fatal(err)
+	}
+
+	// Ensure an explicit namespace is plumbed through
+	cmd = NewDeleteCmd(func(cc ClientConfig, options ...fn.Option) (*fn.Client, func()) {
+		if cc.Namespace != "ns" {
+			t.Fatalf("expected 'ns', got '%v'", cc.Namespace)
+		}
+		return fn.New(), func() {}
+	})
+	cmd.SetArgs([]string{"--namespace", "ns"})
+	if err := cmd.Execute(); err != nil {
+		t.Fatal(err)
+	}
+
+}
+
 // TestDelete_ByName ensures that running delete specifying the name of the
 // function explicitly as an argument invokes the remover appropriately.
 func TestDelete_ByName(t *testing.T) {

docs/reference/func_delete.md

@@ -35,7 +35,7 @@ func delete -n apps myfunc
   -a, --all string         Delete all resources created for a function, eg. Pipelines, Secrets, etc. (Env: $FUNC_ALL) (allowed values: "true", "false") (default "true")
   -c, --confirm            Prompt to confirm all configuration options (Env: $FUNC_CONFIRM)
   -h, --help               help for delete
-  -n, --namespace string   The namespace in which to delete. (Env: $FUNC_NAMESPACE)
+  -n, --namespace string   The namespace in which to delete. (Env: $FUNC_NAMESPACE) (default "default")
   -p, --path string        Path to the project directory (Env: $FUNC_PATH) (default ".")
 ```