feat: Context bind handling default values

pkg/builder/context.go

@@ -17,6 +17,7 @@ import (
 	"github.com/gorilla/sessions"
 	"github.com/labstack/echo/v4"
 	"github.com/mitchellh/mapstructure"
+	"github.com/quarkcloudio/quark-go/v2/pkg/utils/tag"
 )
 
 // Context is the most important part of gin. It allows us to pass variables between middleware,
@@ -157,7 +158,26 @@ func (p *Context) Set(key string, val interface{}) {
 // Bind binds the request body into provided type `i`. The default binder
 // does it based on Content-Type header.
 func (p *Context) Bind(i interface{}) error {
-	return p.EchoContext.Bind(i)
+
+	if err := p.EchoContext.Bind(i); err != nil {
+		return err
+	}
+
+	// Set tag defaults
+	// type Example struct {
+	// 	Page      int                    `default:"1"`
+	// 	Size      int                    `default:"10"`
+	// 	IsBool    bool                   `default:"true"`
+	// 	Keyword   string                 `default:"hello world"`
+	// 	Number    float64                `default:"1.23"`
+	// 	Status    [3]int                 `default:"1,2"`
+	// 	TimeRange []string               `default:"12:30,13:30"`
+	// 	Data      map[string]interface{} `default:"age:18,name:zero"`
+	// }
+	// {Page:1 Size:10 Keyword:hello world Number:1.23 Status:[1 2 0] TimeRange:[12:30 13:30] Data:map[age:18 name:zero]}
+	tag.SetDefaults(reflect.ValueOf(i).Elem())
+
+	return nil
 }
 
 // Validate validates provided `i`. It is usually called after `Context#Bind()`.
@@ -350,7 +370,26 @@ func (p *Context) ClientIP() string {
 // application/json, application/xml, application/x-www-form-urlencoded, multipart/form-data
 // If none of the content types above are matched, it will return a ErrUnprocessableEntity error
 func (p *Context) BodyParser(i interface{}) error {
-	return p.EchoContext.Bind(i)
+
+	if err := p.EchoContext.Bind(i); err != nil {
+		return err
+	}
+
+	// Set tag defaults
+	// type Example struct {
+	// 	Page      int                    `default:"1"`
+	// 	Size      int                    `default:"10"`
+	// 	IsBool    bool                   `default:"true"`
+	// 	Keyword   string                 `default:"hello world"`
+	// 	Number    float64                `default:"1.23"`
+	// 	Status    [3]int                 `default:"1,2"`
+	// 	TimeRange []string               `default:"12:30,13:30"`
+	// 	Data      map[string]interface{} `default:"age:18,name:zero"`
+	// }
+	// {Page:1 Size:10 Keyword:hello world Number:1.23 Status:[1 2 0] TimeRange:[12:30 13:30] Data:map[age:18 name:zero]}
+	tag.SetDefaults(reflect.ValueOf(i).Elem())
+
+	return nil
 }
 
 // 获取请求头数据

pkg/builder/engine.go

@@ -22,7 +22,7 @@ const (
 	AppName = "QuarkGo"
 
 	// 版本号
-	Version = "2.4.0"
+	Version = "2.4.1"
 
 	// 包名
 	PkgName = "github.com/quarkcloudio/quark-go/v2"

pkg/utils/tag/default.go

@@ -0,0 +1,110 @@
+package tag
+
+import (
+	"reflect"
+	"strconv"
+	"strings"
+)
+
+// 设置默认值
+func SetDefaults(value reflect.Value) {
+
+	// 解引用指针类型
+	if value.Kind() == reflect.Ptr {
+		if value.IsNil() {
+			value.Set(reflect.New(value.Type().Elem()))
+		}
+		value = value.Elem()
+	}
+	
+	typ := value.Type()
+
+	for i := 0; i < value.NumField(); i++ {
+		field := value.Field(i)
+		// 嵌套结构体递归处理
+		if field.Kind() == reflect.Struct {
+			SetDefaults(field)
+		}
+		// 检查字段标签中存在default标签并且当前值是该字段类型的零值
+		defaultValue := typ.Field(i).Tag.Get("default")
+		if defaultValue != "" && reflect.DeepEqual(field.Interface(), reflect.Zero(field.Type()).Interface()) {
+			setValue(field, defaultValue)
+		}
+	}
+}
+
+func setSliceFieldValue(field reflect.Value, defaultValue string) {
+
+	values := strings.Split(defaultValue, ",")
+	slice := reflect.MakeSlice(field.Type(), len(values), len(values))
+
+	for key, value := range values {
+		setValue(slice.Index(key), value)
+	}
+	field.Set(slice)
+}
+
+func setArrayFieldValue(field reflect.Value, defaultValue string) {
+
+	for key, value := range strings.Split(defaultValue, ",") {
+		if key >= field.Len() {
+			continue
+		}
+		setValue(field.Index(key), value)
+	}
+}
+
+func setMapFieldValue(field reflect.Value, defaultValue string) {
+
+	mapType := field.Type()
+	mapInstance := reflect.MakeMap(mapType)
+
+	for _, pair := range strings.Split(defaultValue, ",") {
+		kv := strings.Split(pair, ":")
+		if len(kv) != 2 {
+			continue
+		}
+		key := reflect.New(mapType.Key()).Elem()
+		value := reflect.New(mapType.Elem()).Elem()
+
+		setValue(key, kv[0])
+		setValue(value, kv[1])
+
+		mapInstance.SetMapIndex(key, value)
+	}
+
+	field.Set(mapInstance)
+}
+
+// 设置字段值
+func setValue(field reflect.Value, defaultValue string) {
+
+	switch field.Kind() {
+	case reflect.String:
+		field.SetString(defaultValue)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		if intValue, err := strconv.ParseInt(defaultValue, 10, 64); err == nil {
+			field.SetInt(intValue)
+		}
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		if uintValue, err := strconv.ParseUint(defaultValue, 10, 64); err == nil {
+			field.SetUint(uintValue)
+		}
+	case reflect.Float32, reflect.Float64:
+		if floatValue, err := strconv.ParseFloat(defaultValue, 64); err == nil {
+			field.SetFloat(floatValue)
+		}
+	case reflect.Bool:
+		if boolValue, err := strconv.ParseBool(defaultValue); err == nil {
+			field.SetBool(boolValue)
+		}
+	case reflect.Array:
+		setArrayFieldValue(field, defaultValue)
+	case reflect.Slice:
+		setSliceFieldValue(field, defaultValue)
+	case reflect.Map:
+		setMapFieldValue(field, defaultValue)
+	default:
+		field.Set(reflect.ValueOf(defaultValue))
+	}
+}