feat: add more default type for binding (#1056)

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feat
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#### (Optional) Translate the PR title into Chinese.
为参数绑定提供更多的默认类型支持

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en: 为参数绑定提供更多的默认类型支持
zh(optional): add more default type for binding

- 增加了 map、struct、slice 等类型的默认值处理
- 降低 default value 的优先级，避免在做完 json.unmarshal() 后，default value 将其值覆盖

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_typos.toml

@@ -18,4 +18,8 @@ HeaderReferer = "HeaderReferer"
 expectedReferer = "expectedReferer"
 Referer = "Referer"
 O_WRONLY = "O_WRONLY"
-WRONLY = "WRONLY"
+WRONLY = "WRONLY"
+ome = "ome"
+ifModifiedSice = "ifModifiedSice"
+hd = "hd"
+pn = "pn"

pkg/app/server/binding/binder_test.go

@@ -417,10 +417,11 @@ func TestBind_ZeroValueBind(t *testing.T) {
 
 func TestBind_DefaultValueBind(t *testing.T) {
 	var s struct {
-		A int      `default:"15"`
-		B float64  `query:"b" default:"17"`
-		C []int    `default:"15"`
-		D []string `default:"qwe"`
+		A int       `default:"15"`
+		B float64   `query:"b" default:"17"`
+		C []int     `default:"[15]"`
+		D []string  `default:"['qwe','asd']"`
+		F [2]string `default:"['qwe','asd','zxc']"`
 	}
 	req := newMockRequest().
 		SetRequestURI("http://foobar.com")
@@ -432,7 +433,23 @@ func TestBind_DefaultValueBind(t *testing.T) {
 	assert.DeepEqual(t, 15, s.A)
 	assert.DeepEqual(t, float64(17), s.B)
 	assert.DeepEqual(t, 15, s.C[0])
+	assert.DeepEqual(t, 2, len(s.D))
 	assert.DeepEqual(t, "qwe", s.D[0])
+	assert.DeepEqual(t, "asd", s.D[1])
+	assert.DeepEqual(t, 2, len(s.F))
+	assert.DeepEqual(t, "qwe", s.F[0])
+	assert.DeepEqual(t, "asd", s.F[1])
+
+	var s2 struct {
+		F [2]string `default:"['qwe']"`
+	}
+	err = DefaultBinder().Bind(req.Req, &s2, nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	assert.DeepEqual(t, 2, len(s2.F))
+	assert.DeepEqual(t, "qwe", s2.F[0])
+	assert.DeepEqual(t, "", s2.F[1])
 
 	var d struct {
 		D [2]string `default:"qwe"`
@@ -1549,6 +1566,32 @@ func TestBind_Issue1015(t *testing.T) {
 	assert.DeepEqual(t, "asd", result.A)
 }
 
+func TestBind_JSONWithDefault(t *testing.T) {
+	type Req struct {
+		J1 string `json:"j1" default:"j1default"`
+	}
+
+	req := newMockRequest().
+		SetJSONContentType().
+		SetBody([]byte(`{"j1":"j1"}`))
+	var result Req
+	err := DefaultBinder().Bind(req.Req, &result, nil)
+	if err != nil {
+		t.Error(err)
+	}
+	assert.DeepEqual(t, "j1", result.J1)
+
+	result = Req{}
+	req = newMockRequest().
+		SetJSONContentType().
+		SetBody([]byte(`{"j2":"j2"}`))
+	err = DefaultBinder().Bind(req.Req, &result, nil)
+	if err != nil {
+		t.Error(err)
+	}
+	assert.DeepEqual(t, "j1default", result.J1)
+}
+
 func TestBind_WithoutPreBindForTag(t *testing.T) {
 	type BaseQuery struct {
 		Action  string `query:"Action" binding:"required"`

pkg/app/server/binding/internal/decoder/base_type_decoder.go

@@ -69,14 +69,17 @@ func (d *baseTypeFieldTextDecoder) Decode(req *protocol.Request, params param.Pa
 	var defaultValue string
 	for _, tagInfo := range d.tagInfos {
 		if tagInfo.Skip || tagInfo.Key == jsonTag || tagInfo.Key == fileNameTag {
-			defaultValue = tagInfo.Default
 			if tagInfo.Key == jsonTag {
+				defaultValue = tagInfo.Default
 				found := checkRequireJSON(req, tagInfo)
 				if found {
 					err = nil
 				} else {
 					err = fmt.Errorf("'%s' field is a 'required' parameter, but the request body does not have this parameter '%s'", d.fieldName, tagInfo.JSONName)
 				}
+				if len(tagInfo.Default) != 0 && keyExist(req, tagInfo) {
+					defaultValue = ""
+				}
 			}
 			continue
 		}
@@ -94,7 +97,7 @@ func (d *baseTypeFieldTextDecoder) Decode(req *protocol.Request, params param.Pa
 		return err
 	}
 	if len(text) == 0 && len(defaultValue) != 0 {
-		text = defaultValue
+		text = toDefaultValue(d.fieldType, defaultValue)
 	}
 	if !exist && len(text) == 0 {
 		return nil

pkg/app/server/binding/internal/decoder/customized_type_decoder.go

@@ -60,7 +60,12 @@ func (d *customizedFieldTextDecoder) Decode(req *protocol.Request, params param.
 	var defaultValue string
 	for _, tagInfo := range d.tagInfos {
 		if tagInfo.Skip || tagInfo.Key == jsonTag || tagInfo.Key == fileNameTag {
-			defaultValue = tagInfo.Default
+			if tagInfo.Key == jsonTag {
+				defaultValue = tagInfo.Default
+				if len(tagInfo.Default) != 0 && keyExist(req, tagInfo) {
+					defaultValue = ""
+				}
+			}
 			continue
 		}
 		text, exist = tagInfo.Getter(req, params, tagInfo.Value)
@@ -73,7 +78,7 @@ func (d *customizedFieldTextDecoder) Decode(req *protocol.Request, params param.
 		return nil
 	}
 	if len(text) == 0 && len(defaultValue) != 0 {
-		text = defaultValue
+		text = toDefaultValue(d.fieldType, defaultValue)
 	}
 
 	v, err := d.decodeFunc(req, params, text)

pkg/app/server/binding/internal/decoder/decoder.go

@@ -124,7 +124,7 @@ func getFieldDecoder(pInfo parentInfos, field reflect.StructField, index int, by
 	// JSONName is like 'a.b.c' for 'required validate'
 	fieldTagInfos, newParentJSONName, needValidate := lookupFieldTags(field, pInfo.JSONName, config)
 	if len(fieldTagInfos) == 0 && !config.DisableDefaultTag {
-		fieldTagInfos = getDefaultFieldTags(field)
+		fieldTagInfos, newParentJSONName = getDefaultFieldTags(field, pInfo.JSONName)
 	}
 	if len(byTag) != 0 {
 		fieldTagInfos = getFieldTagInfoByTag(field, byTag)

pkg/app/server/binding/internal/decoder/gjson_required.go

@@ -47,3 +47,12 @@ func checkRequireJSON(req *protocol.Request, tagInfo TagInfo) bool {
 	}
 	return true
 }
+
+func keyExist(req *protocol.Request, tagInfo TagInfo) bool {
+	ct := bytesconv.B2s(req.Header.ContentType())
+	if utils.FilterContentType(ct) != consts.MIMEApplicationJSON {
+		return false
+	}
+	result := gjson.GetBytes(req.Body(), tagInfo.JSONName)
+	return result.Exists()
+}

pkg/app/server/binding/internal/decoder/map_type_decoder.go

@@ -61,14 +61,17 @@ func (d *mapTypeFieldTextDecoder) Decode(req *protocol.Request, params param.Par
 	var defaultValue string
 	for _, tagInfo := range d.tagInfos {
 		if tagInfo.Skip || tagInfo.Key == jsonTag || tagInfo.Key == fileNameTag {
-			defaultValue = tagInfo.Default
 			if tagInfo.Key == jsonTag {
+				defaultValue = tagInfo.Default
 				found := checkRequireJSON(req, tagInfo)
 				if found {
 					err = nil
 				} else {
 					err = fmt.Errorf("'%s' field is a 'required' parameter, but the request does not have this parameter", d.fieldName)
 				}
+				if len(tagInfo.Default) != 0 && keyExist(req, tagInfo) {
+					defaultValue = ""
+				}
 			}
 			continue
 		}
@@ -86,7 +89,7 @@ func (d *mapTypeFieldTextDecoder) Decode(req *protocol.Request, params param.Par
 		return err
 	}
 	if len(text) == 0 && len(defaultValue) != 0 {
-		text = defaultValue
+		text = toDefaultValue(d.fieldType, defaultValue)
 	}
 	if !exist && len(text) == 0 {
 		return nil

pkg/app/server/binding/internal/decoder/slice_type_decoder.go

@@ -61,16 +61,20 @@ func (d *sliceTypeFieldTextDecoder) Decode(req *protocol.Request, params param.P
 	var texts []string
 	var defaultValue string
 	var bindRawBody bool
+	var isDefault bool
 	for _, tagInfo := range d.tagInfos {
 		if tagInfo.Skip || tagInfo.Key == jsonTag || tagInfo.Key == fileNameTag {
-			defaultValue = tagInfo.Default
 			if tagInfo.Key == jsonTag {
+				defaultValue = tagInfo.Default
 				found := checkRequireJSON(req, tagInfo)
 				if found {
 					err = nil
 				} else {
 					err = fmt.Errorf("'%s' field is a 'required' parameter, but the request does not have this parameter", d.fieldName)
 				}
+				if len(tagInfo.Default) != 0 && keyExist(req, tagInfo) { //
+					defaultValue = ""
+				}
 			}
 			continue
 		}
@@ -91,7 +95,9 @@ func (d *sliceTypeFieldTextDecoder) Decode(req *protocol.Request, params param.P
 		return err
 	}
 	if len(texts) == 0 && len(defaultValue) != 0 {
+		defaultValue = toDefaultValue(d.fieldType, defaultValue)
 		texts = append(texts, defaultValue)
+		isDefault = true
 	}
 	if len(texts) == 0 {
 		return nil
@@ -113,7 +119,7 @@ func (d *sliceTypeFieldTextDecoder) Decode(req *protocol.Request, params param.P
 	}
 
 	if d.isArray {
-		if len(texts) != field.Len() {
+		if len(texts) != field.Len() && !isDefault {
 			return fmt.Errorf("%q is not valid value for %s", texts, field.Type().String())
 		}
 	} else {
@@ -135,6 +141,13 @@ func (d *sliceTypeFieldTextDecoder) Decode(req *protocol.Request, params param.P
 		elemKind = t.Kind()
 		ptrDepth++
 	}
+	if isDefault {
+		err = hJson.Unmarshal(bytesconv.S2b(texts[0]), reqValue.Field(d.index).Addr().Interface())
+		if err != nil {
+			return fmt.Errorf("using '%s' to unmarshal field '%s: %s' failed, %v", texts[0], d.fieldName, d.fieldType.String(), err)
+		}
+		return nil
+	}
 
 	for idx, text := range texts {
 		var vv reflect.Value
@@ -218,33 +231,3 @@ func getSliceFieldDecoder(field reflect.StructField, index int, tagInfos []TagIn
 		isArray: isArray,
 	}}, nil
 }
-
-func stringToValue(elemType reflect.Type, text string, req *protocol.Request, params param.Params, config *DecodeConfig) (v reflect.Value, err error) {
-	v = reflect.New(elemType).Elem()
-	if customizedFunc, exist := config.TypeUnmarshalFuncs[elemType]; exist {
-		val, err := customizedFunc(req, params, text)
-		if err != nil {
-			return reflect.Value{}, err
-		}
-		return val, nil
-	}
-	switch elemType.Kind() {
-	case reflect.Struct:
-		err = hJson.Unmarshal(bytesconv.S2b(text), v.Addr().Interface())
-	case reflect.Map:
-		err = hJson.Unmarshal(bytesconv.S2b(text), v.Addr().Interface())
-	case reflect.Array, reflect.Slice:
-		// do nothing
-	default:
-		decoder, err := SelectTextDecoder(elemType)
-		if err != nil {
-			return reflect.Value{}, fmt.Errorf("unsupported type %s for slice/array", elemType.String())
-		}
-		err = decoder.UnmarshalString(text, v, config.LooseZeroMode)
-		if err != nil {
-			return reflect.Value{}, fmt.Errorf("unable to decode '%s' as %s: %w", text, elemType.String(), err)
-		}
-	}
-
-	return v, err
-}

pkg/app/server/binding/internal/decoder/sonic_required.go

@@ -60,3 +60,12 @@ func stringSliceForInterface(s string) (ret []interface{}) {
 	}
 	return
 }
+
+func keyExist(req *protocol.Request, tagInfo TagInfo) bool {
+	ct := bytesconv.B2s(req.Header.ContentType())
+	if utils.FilterContentType(ct) != consts.MIMEApplicationJSON {
+		return false
+	}
+	node, _ := sonic.Get(req.Body(), stringSliceForInterface(tagInfo.JSONName)...)
+	return node.Exists()
+}

pkg/app/server/binding/internal/decoder/struct_type_decoder.go

@@ -38,14 +38,17 @@ func (d *structTypeFieldTextDecoder) Decode(req *protocol.Request, params param.
 	var defaultValue string
 	for _, tagInfo := range d.tagInfos {
 		if tagInfo.Skip || tagInfo.Key == jsonTag || tagInfo.Key == fileNameTag {
-			defaultValue = tagInfo.Default
 			if tagInfo.Key == jsonTag {
+				defaultValue = tagInfo.Default
 				found := checkRequireJSON(req, tagInfo)
 				if found {
 					err = nil
 				} else {
 					err = fmt.Errorf("'%s' field is a 'required' parameter, but the request does not have this parameter", d.fieldName)
 				}
+				if len(tagInfo.Default) != 0 && keyExist(req, tagInfo) {
+					defaultValue = ""
+				}
 			}
 			continue
 		}
@@ -63,7 +66,7 @@ func (d *structTypeFieldTextDecoder) Decode(req *protocol.Request, params param.
 		return err
 	}
 	if len(text) == 0 && len(defaultValue) != 0 {
-		text = defaultValue
+		text = toDefaultValue(d.fieldType, defaultValue)
 	}
 	if !exist && len(text) == 0 {
 		return nil

pkg/app/server/binding/internal/decoder/tag.go

@@ -87,7 +87,7 @@ func lookupFieldTags(field reflect.StructField, parentJSONName string, config *D
 			tagValue = field.Name
 		}
 		skip := false
-		jsonName := ""
+		jsonName := parentJSONName + "." + field.Name
 		if tag == jsonTag {
 			jsonName = parentJSONName + "." + tagValue
 		}
@@ -120,16 +120,18 @@ func lookupFieldTags(field reflect.StructField, parentJSONName string, config *D
 	return tagInfos, newParentJSONName, needValidate
 }
 
-func getDefaultFieldTags(field reflect.StructField) (tagInfos []TagInfo) {
+func getDefaultFieldTags(field reflect.StructField, parentJSONName string) (tagInfos []TagInfo, newParentJSONName string) {
 	defaultVal := ""
 	if val, ok := field.Tag.Lookup(defaultTag); ok {
 		defaultVal = val
 	}
 
 	tags := []string{pathTag, formTag, queryTag, cookieTag, headerTag, jsonTag, fileNameTag}
 	for _, tag := range tags {
-		tagInfos = append(tagInfos, TagInfo{Key: tag, Value: field.Name, Default: defaultVal})
+		jsonName := strings.TrimPrefix(parentJSONName+"."+field.Name, ".")
+		tagInfos = append(tagInfos, TagInfo{Key: tag, Value: field.Name, Default: defaultVal, JSONName: jsonName})
 	}
+	newParentJSONName = strings.TrimPrefix(parentJSONName+"."+field.Name, ".")
 
 	return
 }