improve kv CLI to remove data or custom metadata using kv patch (#18067)

* improve kv CLI to remove data or custom metadata using kv patch

* CL

* adding a comment

changelog/18067.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+cli/kv: improve kv CLI to remove data or custom metadata using kv patch
+```

command/kv_metadata_patch.go

@@ -20,12 +20,13 @@ var (
 type KVMetadataPatchCommand struct {
 	*BaseCommand
 
-	flagMaxVersions        int
-	flagCASRequired        BoolPtr
-	flagDeleteVersionAfter time.Duration
-	flagCustomMetadata     map[string]string
-	flagMount              string
-	testStdin              io.Reader // for tests
+	flagMaxVersions          int
+	flagCASRequired          BoolPtr
+	flagDeleteVersionAfter   time.Duration
+	flagCustomMetadata       map[string]string
+	flagRemoveCustomMetadata []string
+	flagMount                string
+	testStdin                io.Reader // for tests
 }
 
 func (c *KVMetadataPatchCommand) Synopsis() string {
@@ -65,6 +66,10 @@ Usage: vault kv metadata patch [options] KEY
 
       $ vault kv metadata patch -mount=secret -custom-metadata=foo=abc -custom-metadata=bar=123 foo
 
+  To remove custom meta data from the corresponding path in the key-value store, kv metadata patch can be used.
+
+      $ vault kv metadata patch -mount=secret -remove-custom-metadata=bar foo
+
   Additional flags and more advanced use cases are detailed below.
 
 ` + c.Flags().Help()
@@ -111,6 +116,13 @@ func (c *KVMetadataPatchCommand) Flags() *FlagSets {
 		This can be specified multiple times to add multiple pieces of metadata.`,
 	})
 
+	f.StringSliceVar(&StringSliceVar{
+		Name:    "remove-custom-metadata",
+		Target:  &c.flagRemoveCustomMetadata,
+		Default: []string{},
+		Usage:   "Key to remove from custom metadata. To specify multiple values, specify this flag multiple times.",
+	})
+
 	f.StringVar(&StringVar{
 		Name:    "mount",
 		Target:  &c.flagMount,
@@ -198,7 +210,7 @@ func (c *KVMetadataPatchCommand) Run(args []string) int {
 
 	fullPath := addPrefixToKVPath(partialPath, mountPath, "metadata")
 
-	data := map[string]interface{}{}
+	data := make(map[string]interface{}, 0)
 
 	if c.flagMaxVersions >= 0 {
 		data["max_versions"] = c.flagMaxVersions
@@ -212,10 +224,19 @@ func (c *KVMetadataPatchCommand) Run(args []string) int {
 		data["delete_version_after"] = c.flagDeleteVersionAfter.String()
 	}
 
-	if len(c.flagCustomMetadata) > 0 {
-		data["custom_metadata"] = c.flagCustomMetadata
+	customMetadata := make(map[string]interface{})
+
+	for key, value := range c.flagCustomMetadata {
+		customMetadata[key] = value
 	}
 
+	for _, key := range c.flagRemoveCustomMetadata {
+		// A null in a JSON merge patch payload will remove the associated key
+		customMetadata[key] = nil
+	}
+
+	data["custom_metadata"] = customMetadata
+
 	secret, err := client.Logical().JSONMergePatch(context.Background(), fullPath, data)
 	if err != nil {
 		c.UI.Error(fmt.Sprintf("Error writing data to %s: %s", fullPath, err))

command/kv_metadata_patch_test.go

@@ -122,6 +122,29 @@ func TestKvMetadataPatchCommand_Flags(t *testing.T) {
 				},
 			},
 		},
+		{
+			"remove-custom_metadata",
+			[]string{"-custom-metadata=baz=ghi", "-remove-custom-metadata=foo"},
+			"Success!",
+			0,
+			map[string]interface{}{
+				"custom_metadata": map[string]interface{}{
+					"bar": "def",
+					"baz": "ghi",
+				},
+			},
+		},
+		{
+			"remove-custom_metadata-multiple",
+			[]string{"-custom-metadata=baz=ghi", "-remove-custom-metadata=foo", "-remove-custom-metadata=bar"},
+			"Success!",
+			0,
+			map[string]interface{}{
+				"custom_metadata": map[string]interface{}{
+					"baz": "ghi",
+				},
+			},
+		},
 		{
 			"delete_version_after_success",
 			[]string{"-delete-version-after=5s"},

command/kv_patch.go

@@ -21,10 +21,11 @@ var (
 type KVPatchCommand struct {
 	*BaseCommand
 
-	flagCAS    int
-	flagMethod string
-	flagMount  string
-	testStdin  io.Reader // for tests
+	flagCAS        int
+	flagMethod     string
+	flagMount      string
+	testStdin      io.Reader // for tests
+	flagRemoveData []string
 }
 
 func (c *KVPatchCommand) Synopsis() string {
@@ -76,6 +77,10 @@ Usage: vault kv patch [options] KEY [DATA]
 
       $ vault kv patch -mount=secret -method=rw foo bar=baz
 
+  To remove data from the corresponding path in the key-value store, kv patch can be used.
+
+      $ vault kv patch -mount=secret -remove-data=bar foo
+
   Additional flags and more advanced use cases are detailed below.
 
 ` + c.Flags().Help()
@@ -117,6 +122,13 @@ func (c *KVPatchCommand) Flags() *FlagSets {
 		v2 secrets.`,
 	})
 
+	f.StringSliceVar(&StringSliceVar{
+		Name:    "remove-data",
+		Target:  &c.flagRemoveData,
+		Default: []string{},
+		Usage:   "Key to remove from data. To specify multiple values, specify this flag multiple times.",
+	})
+
 	return set
 }
 
@@ -147,7 +159,7 @@ func (c *KVPatchCommand) Run(args []string) int {
 	case len(args) < 1:
 		c.UI.Error(fmt.Sprintf("Not enough arguments (expected >1, got %d)", len(args)))
 		return 1
-	case len(args) == 1:
+	case len(c.flagRemoveData) == 0 && len(args) == 1:
 		c.UI.Error("Must supply data")
 		return 1
 	}
@@ -211,6 +223,16 @@ func (c *KVPatchCommand) Run(args []string) int {
 		return 2
 	}
 
+	// collecting data to be removed
+	if newData == nil {
+		newData = make(map[string]interface{})
+	}
+
+	for _, key := range c.flagRemoveData {
+		// A null in a JSON merge patch payload will remove the associated key
+		newData[key] = nil
+	}
+
 	// Check the method and behave accordingly
 	var secret *api.Secret
 	var code int

vault/external_tests/kv/kv_patch_test.go

@@ -249,6 +249,7 @@ func TestKV_Patch_RootToken(t *testing.T) {
 		data := map[string]interface{}{
 			"data": map[string]interface{}{
 				"bar": "baz",
+				"foo": "qux",
 			},
 		}
 
@@ -263,6 +264,7 @@ func TestKV_Patch_RootToken(t *testing.T) {
 		data := map[string]interface{}{
 			"data": map[string]interface{}{
 				"bar": "quux",
+				"foo": nil,
 			},
 		}
 		return client.Logical().JSONMergePatch(context.Background(), "kv/data/foo", data)
@@ -288,4 +290,8 @@ func TestKV_Patch_RootToken(t *testing.T) {
 	if bar != "quux" {
 		t.Fatalf("expected bar to be quux but it was %q", bar)
 	}
+
+	if _, ok := secret.Data["data"].(map[string]interface{})["foo"]; ok {
+		t.Fatalf("expected data not to include foo")
+	}
 }