feat: Add support for serialization of anonymous fields in HTTP client(httpc) (#4676)

Co-authored-by: 李安琳 <anlynn@gmail.com>

core/mapping/marshaler.go

@@ -13,6 +13,15 @@ const (
 
 // Marshal marshals the given val and returns the map that contains the fields.
 // optional=another is not implemented, and it's hard to implement and not commonly used.
+// support anonymous field, e.g.:
+//
+//	type Foo struct {
+//		Token string `header:"token"`
+//	}
+//	type FooB struct {
+//		Foo
+//		Bar string  `json:"bar"`
+//	}
 func Marshal(val any) (map[string]map[string]any, error) {
 	ret := make(map[string]map[string]any)
 	tp := reflect.TypeOf(val)
@@ -69,15 +78,35 @@ func processMember(field reflect.StructField, value reflect.Value,
 		val = fmt.Sprint(val)
 	}
 
-	m, ok := collector[tag]
-	if ok {
-		m[key] = val
-	} else {
-		m = map[string]any{
-			key: val,
+	if field.Anonymous {
+		anonCollector, err := Marshal(val)
+		if err != nil {
+			return err
 		}
+		for anonTag, anonMap := range anonCollector {
+			for anonKey, anonVal := range anonMap {
+				m, ok := collector[anonTag]
+				if ok {
+					m[anonKey] = anonVal
+				} else {
+					m = map[string]any{
+						anonKey: anonVal,
+					}
+				}
+				collector[anonTag] = m
+			}
+		}
+	} else {
+		m, ok := collector[tag]
+		if ok {
+			m[key] = val
+		} else {
+			m = map[string]any{
+				key: val,
+			}
+		}
+		collector[tag] = m
 	}
-	collector[tag] = m
 
 	return nil
 }

core/mapping/marshaler_test.go

@@ -27,6 +27,99 @@ func TestMarshal(t *testing.T) {
 	assert.True(t, m[emptyTag]["Anonymous"].(bool))
 }
 
+func TestMarshal_Anonymous(t *testing.T) {
+	type BaseHeader struct {
+		Token string `header:"token"`
+	}
+	v := struct {
+		Name    string `json:"name"`
+		Address string `json:"address,options=[beijing,shanghai]"`
+		Age     int    `json:"age"`
+		BaseHeader
+	}{
+		Name:    "kevin",
+		Address: "shanghai",
+		Age:     20,
+		BaseHeader: BaseHeader{
+			Token: "token_xxx",
+		},
+	}
+	m, err := Marshal(v)
+	assert.Nil(t, err)
+	assert.Equal(t, "kevin", m["json"]["name"])
+	assert.Equal(t, "shanghai", m["json"]["address"])
+	assert.Equal(t, 20, m["json"]["age"].(int))
+	assert.Equal(t, "token_xxx", m["header"]["token"])
+
+	v1 := struct {
+		Name    string `json:"name"`
+		Address string `json:"address,options=[beijing,shanghai]"`
+		Age     int    `json:"age"`
+		BaseHeader
+	}{
+		Name:    "kevin",
+		Address: "shanghai",
+		Age:     20,
+	}
+	m1, err1 := Marshal(v1)
+	assert.Nil(t, err1)
+	assert.Equal(t, "kevin", m1["json"]["name"])
+	assert.Equal(t, "shanghai", m1["json"]["address"])
+	assert.Equal(t, 20, m1["json"]["age"].(int))
+
+	type AnotherHeader struct {
+		Version string `header:"version"`
+	}
+	v2 := struct {
+		Name    string `json:"name"`
+		Address string `json:"address,options=[beijing,shanghai]"`
+		Age     int    `json:"age"`
+		BaseHeader
+		AnotherHeader
+	}{
+		Name:    "kevin",
+		Address: "shanghai",
+		Age:     20,
+		BaseHeader: BaseHeader{
+			Token: "token_xxx",
+		},
+		AnotherHeader: AnotherHeader{
+			Version: "v1.0",
+		},
+	}
+	m2, err2 := Marshal(v2)
+	assert.Nil(t, err2)
+	assert.Equal(t, "kevin", m2["json"]["name"])
+	assert.Equal(t, "shanghai", m2["json"]["address"])
+	assert.Equal(t, 20, m2["json"]["age"].(int))
+	assert.Equal(t, "token_xxx", m2["header"]["token"])
+	assert.Equal(t, "v1.0", m2["header"]["version"])
+
+	type PointerHeader struct {
+		Ref *string `header:"ref"`
+	}
+	ref := "reference"
+	v3 := struct {
+		Name    string `json:"name"`
+		Address string `json:"address,options=[beijing,shanghai]"`
+		Age     int    `json:"age"`
+		PointerHeader
+	}{
+		Name:    "kevin",
+		Address: "shanghai",
+		Age:     20,
+		PointerHeader: PointerHeader{
+			Ref: &ref,
+		},
+	}
+	m3, err3 := Marshal(v3)
+	assert.Nil(t, err3)
+	assert.Equal(t, "kevin", m3["json"]["name"])
+	assert.Equal(t, "shanghai", m3["json"]["address"])
+	assert.Equal(t, 20, m3["json"]["age"].(int))
+	assert.Equal(t, "reference", *m3["header"]["ref"].(*string))
+}
+
 func TestMarshal_Ptr(t *testing.T) {
 	v := &struct {
 		Name      string `path:"name"`