feat: add struct binding

pkg/app/server/binding_v2/base_type_decoder.go

@@ -5,15 +5,17 @@ import (
 	"reflect"
 
 	"github.com/cloudwego/hertz/pkg/app/server/binding_v2/text_decoder"
+	"github.com/cloudwego/hertz/pkg/common/utils"
 	"github.com/cloudwego/hertz/pkg/protocol"
 )
 
 type baseTypeFieldTextDecoder struct {
-	index     int
-	fieldName string
-	tagInfos  []TagInfo // query,param,header,respHeader ...
-	fieldType reflect.Type
-	decoder   text_decoder.TextDecoder
+	index       int
+	parentIndex []int
+	fieldName   string
+	tagInfos    []TagInfo // query,param,header,respHeader ...
+	fieldType   reflect.Type
+	decoder     text_decoder.TextDecoder
 }
 
 func (d *baseTypeFieldTextDecoder) Decode(req *protocol.Request, params PathParams, reqValue reflect.Value) error {
@@ -24,6 +26,11 @@ func (d *baseTypeFieldTextDecoder) Decode(req *protocol.Request, params PathPara
 		if tagInfo.Key == jsonTag {
 			continue
 		}
+		if tagInfo.Key == headerTag {
+			tmp := []byte(tagInfo.Value)
+			utils.NormalizeHeaderKey(tmp, req.Header.IsDisableNormalizing())
+			tagInfo.Value = string(tmp)
+		}
 		ret := tagInfo.Getter(req, params, tagInfo.Value)
 		defaultValue = tagInfo.Default
 		if len(ret) != 0 {
@@ -40,18 +47,43 @@ func (d *baseTypeFieldTextDecoder) Decode(req *protocol.Request, params PathPara
 	}
 
 	var err error
+	// 找到该 field 的父 struct 的 reflect.Value
+	for _, idx := range d.parentIndex {
+		if reqValue.Kind() == reflect.Ptr && reqValue.IsNil() {
+			nonNilVal, ptrDepth := GetNonNilReferenceValue(reqValue)
+			reqValue.Set(ReferenceValue(nonNilVal, ptrDepth))
+		}
+		for reqValue.Kind() == reflect.Ptr {
+			reqValue = reqValue.Elem()
+		}
+		reqValue = reqValue.Field(idx)
+	}
+
+	// 父 struct 有可能也是一个指针，所以需要再处理一次才能得到最终的父Value(非nil的reflect.Value)
+	for reqValue.Kind() == reflect.Ptr {
+		if reqValue.IsNil() {
+			nonNilVal, ptrDepth := GetNonNilReferenceValue(reqValue)
+			reqValue.Set(ReferenceValue(nonNilVal, ptrDepth))
+		}
+		reqValue = reqValue.Elem()
+	}
 
-	// Pointer support for struct elems
+	// 根据最终的 Struct，获取对应 field 的 reflect.Value
 	field := reqValue.Field(d.index)
 	if field.Kind() == reflect.Ptr {
-		elem := reflect.New(d.fieldType)
-		err = d.decoder.UnmarshalString(text, elem.Elem())
+		// 如果是指针则新建一个reflect.Value，然后赋值给指针
+		t := field.Type()
+		var ptrDepth int
+		for t.Kind() == reflect.Ptr {
+			t = t.Elem()
+			ptrDepth++
+		}
+		var vv reflect.Value
+		vv, err := stringToValue(t, text)
 		if err != nil {
-			return fmt.Errorf("unable to decode '%s' as %s: %w", text, d.fieldType.Name(), err)
+			return err
 		}
-
-		field.Set(elem)
-
+		field.Set(ReferenceValue(vv, ptrDepth))
 		return nil
 	}
 
@@ -64,7 +96,7 @@ func (d *baseTypeFieldTextDecoder) Decode(req *protocol.Request, params PathPara
 	return nil
 }
 
-func getBaseTypeTextDecoder(field reflect.StructField, index int, tagInfos []TagInfo) ([]decoder, error) {
+func getBaseTypeTextDecoder(field reflect.StructField, index int, tagInfos []TagInfo, parentIdx []int) ([]decoder, error) {
 	for idx, tagInfo := range tagInfos {
 		switch tagInfo.Key {
 		case pathTag:
@@ -86,7 +118,7 @@ func getBaseTypeTextDecoder(field reflect.StructField, index int, tagInfos []Tag
 	}
 
 	fieldType := field.Type
-	if field.Type.Kind() == reflect.Ptr {
+	for field.Type.Kind() == reflect.Ptr {
 		fieldType = field.Type.Elem()
 	}
 
@@ -96,11 +128,12 @@ func getBaseTypeTextDecoder(field reflect.StructField, index int, tagInfos []Tag
 	}
 
 	fieldDecoder := &baseTypeFieldTextDecoder{
-		index:     index,
-		fieldName: field.Name,
-		tagInfos:  tagInfos,
-		decoder:   textDecoder,
-		fieldType: fieldType,
+		index:       index,
+		parentIndex: parentIdx,
+		fieldName:   field.Name,
+		tagInfos:    tagInfos,
+		decoder:     textDecoder,
+		fieldType:   fieldType,
 	}
 
 	return []decoder{fieldDecoder}, nil

pkg/app/server/binding_v2/binder.go

@@ -38,6 +38,9 @@ func (b *Bind) Bind(req *protocol.Request, params PathParams, v interface{}) err
 	if rv.Kind() != reflect.Pointer || rv.IsNil() {
 		return fmt.Errorf("receiver must be a non-nil pointer")
 	}
+	if rv.Kind() == reflect.Map {
+		return nil
+	}
 	cached, ok := b.decoderCache.Load(typeID)
 	if ok {
 		// cached decoder, fast path