feat: add string to map in httpx parse method (#2459)

* chore: add string to map in httpx parse method

* feat: add httpx parse stringToMap method test

core/mapping/unmarshaler.go

@@ -207,6 +207,8 @@ func (u *Unmarshaler) processFieldNotFromString(field reflect.StructField, value
 		return u.fillMap(field, value, mapValue)
 	case valueKind == reflect.String && typeKind == reflect.Slice:
 		return u.fillSliceFromString(fieldType, value, mapValue)
+	case valueKind == reflect.String && typeKind == reflect.Map:
+		return u.fillMapFromString(value, mapValue)
 	case valueKind == reflect.String && derefedFieldType == durationType:
 		return fillDurationValue(fieldType.Kind(), value, mapValue.(string))
 	default:
@@ -530,6 +532,23 @@ func (u *Unmarshaler) fillSliceFromString(fieldType reflect.Type, value reflect.
 	return nil
 }
 
+func (u *Unmarshaler) fillMapFromString(value reflect.Value, mapValue interface{}) error {
+	switch v := mapValue.(type) {
+	case fmt.Stringer:
+		if err := jsonx.UnmarshalFromString(v.String(), value.Addr().Interface()); err != nil {
+			return err
+		}
+	case string:
+		if err := jsonx.UnmarshalFromString(v, value.Addr().Interface()); err != nil {
+			return err
+		}
+	default:
+		return errUnsupportedType
+	}
+
+	return nil
+}
+
 func (u *Unmarshaler) fillSliceValue(slice reflect.Value, index int,
 	baseKind reflect.Kind, value interface{}) error {
 	ithVal := slice.Index(index)

core/mapping/unmarshaler_test.go

@@ -467,6 +467,39 @@ func TestUnmarshalIntSliceFromString(t *testing.T) {
 	ast.Equal(2, v.Values[1])
 }
 
+func TestUnmarshalStringMapFromString(t *testing.T) {
+	var v struct {
+		Sort map[string]string `key:"sort"`
+	}
+	m := map[string]interface{}{
+		"sort": `{"value":"ascend","emptyStr":""}`,
+	}
+
+	ast := assert.New(t)
+	ast.Nil(UnmarshalKey(m, &v))
+	ast.Equal(2, len(v.Sort))
+	ast.Equal("ascend", v.Sort["value"])
+	ast.Equal("", v.Sort["emptyStr"])
+}
+
+func TestUnmarshalStringSliceMapFromString(t *testing.T) {
+	var v struct {
+		Filter map[string][]string `key:"filter"`
+	}
+	m := map[string]interface{}{
+		"filter": `{"assignType":null,"status":["process","comment"],"rate":[]}`,
+	}
+
+	ast := assert.New(t)
+	ast.Nil(UnmarshalKey(m, &v))
+	ast.Equal(3, len(v.Filter))
+	ast.Equal([]string(nil), v.Filter["assignType"])
+	ast.Equal(2, len(v.Filter["status"]))
+	ast.Equal("process", v.Filter["status"][0])
+	ast.Equal("comment", v.Filter["status"][1])
+	ast.Equal(0, len(v.Filter["rate"]))
+}
+
 func TestUnmarshalStruct(t *testing.T) {
 	type address struct {
 		City          string `key:"city"`