add variadic

options/options.go

@@ -151,15 +151,29 @@ func ContentType(ct string) Option {
 }
 
 // Metadata pass additional metadata
-func Metadata(md any) Option {
+func Metadata(md ...any) Option {
 	result := metadata.Metadata{}
-	switch vt := md.(type) {
+
+	if len(md) > 1 {
+		var tmp []string
+		for _, val := range md {
+			switch vt := val.(type) {
+			case string:
+				tmp = append(tmp, vt)
+			default:
+				return func(src interface{}) error {
+					return Set(src, result, ".Metadata")
+				}
+			}
+		}
+		result.Set(tmp...)
+	} else if len(md) == 1 {
+		switch vt := md[0].(type) {
 		case metadata.Metadata:
 			result = metadata.Copy(vt)
 		case map[string]string:
 			result = metadata.Copy(vt)
-	case []string:
-		result.Set(vt...)
+		}
 	}
 
 	return func(src interface{}) error {

options/options_test.go

@@ -100,7 +100,7 @@ func TestMetadataAny(t *testing.T) {
 	}{
 		{
 			"strings_even",
-			[]string{"key1", "val1", "key2", "val2"},
+			[]any{"key1", "val1", "key2", "val2"},
 			metadata.Metadata{
 				"Key1": "val1",
 				"Key2": "val2",
@@ -108,18 +108,18 @@ func TestMetadataAny(t *testing.T) {
 		},
 		{
 			"strings_odd",
-			[]string{"key1", "val1", "key2"},
+			[]any{"key1", "val1", "key2"},
 			metadata.Metadata{
 				"Key1": "val1",
 			},
 		},
 		{
-			"map",
-			map[string]string{
+			Name: "map",
+			Data: map[string]string{
 				"key1": "val1",
 				"key2": "val2",
 			},
-			metadata.Metadata{
+			Expected: metadata.Metadata{
 				"Key1": "val1",
 				"Key2": "val2",
 			},
@@ -141,7 +141,13 @@ func TestMetadataAny(t *testing.T) {
 		t.Run(tt.Name, func(t *testing.T) {
 			src := &s{}
 			var opts []options.Option
-			opts = append(opts, options.Metadata(tt.Data))
+			switch valData := tt.Data.(type) {
+			case []any:
+				opts = append(opts, options.Metadata(valData...))
+			case map[string]string, metadata.Metadata:
+				opts = append(opts, options.Metadata(valData))
+			}
+
 			for _, o := range opts {
 				if err := o(src); err != nil {
 					t.Fatal(err)