refactor: move typemap.go to maputil package and add document for it

maputil/typemap.go

@@ -0,0 +1,180 @@
+package maputil
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+)
+
+var mapHandlers = map[reflect.Kind]func(reflect.Value, reflect.Value) error{
+	reflect.String:     convertNormal,
+	reflect.Int:        convertNormal,
+	reflect.Int16:      convertNormal,
+	reflect.Int32:      convertNormal,
+	reflect.Int64:      convertNormal,
+	reflect.Uint:       convertNormal,
+	reflect.Uint16:     convertNormal,
+	reflect.Uint32:     convertNormal,
+	reflect.Uint64:     convertNormal,
+	reflect.Float32:    convertNormal,
+	reflect.Float64:    convertNormal,
+	reflect.Uint8:      convertNormal,
+	reflect.Int8:       convertNormal,
+	reflect.Struct:     convertNormal,
+	reflect.Complex64:  convertNormal,
+	reflect.Complex128: convertNormal,
+}
+
+var _ = func() struct{} {
+	mapHandlers[reflect.Map] = convertMap
+	mapHandlers[reflect.Array] = convertSlice
+	mapHandlers[reflect.Slice] = convertSlice
+	return struct{}{}
+}()
+
+// MapTo try to map any interface to struct or base type
+/*
+	Eg:
+		v := map[string]interface{}{
+			"service":map[string]interface{}{
+				"ip":"127.0.0.1",
+				"port":1234,
+			},
+			version:"v1.0.01"
+		}
+
+		type Target struct {
+			Service struct {
+				Ip string `json:"ip"`
+				Port int `json:"port"`
+			} `json:"service"`
+			Ver string `json:"version"`
+		}
+
+		var dist Target
+		if err := typemap.MapTo(v,&dist); err != nil {
+			log.Println(err)
+			return
+		}
+
+		log.Println(dist)
+
+*/
+func MapTo(src any, dst any) error {
+
+	dstRef := reflect.ValueOf(dst)
+	if dstRef.Kind() != reflect.Ptr {
+		return fmt.Errorf("dst is not ptr")
+	}
+
+	dstRef = reflect.Indirect(dstRef)
+
+	srcRef := reflect.ValueOf(src)
+	if srcRef.Kind() == reflect.Ptr || srcRef.Kind() == reflect.Interface {
+		srcRef = srcRef.Elem()
+	}
+	if f, ok := mapHandlers[srcRef.Kind()]; ok {
+		return f(srcRef, dstRef)
+	}
+
+	return fmt.Errorf("no implemented:%s", srcRef.Type())
+}
+
+func convertNormal(src reflect.Value, dst reflect.Value) error {
+	if dst.CanSet() {
+		if src.Type() == dst.Type() {
+			dst.Set(src)
+		} else if src.CanConvert(dst.Type()) {
+			dst.Set(src.Convert(dst.Type()))
+		} else {
+			return fmt.Errorf("can not convert:%s:%s", src.Type().String(), dst.Type().String())
+		}
+	}
+	return nil
+}
+
+func convertSlice(src reflect.Value, dst reflect.Value) error {
+	if dst.Kind() != reflect.Array && dst.Kind() != reflect.Slice {
+		return fmt.Errorf("error type:%s", dst.Type().String())
+	}
+	l := src.Len()
+	target := reflect.MakeSlice(dst.Type(), l, l)
+	if dst.CanSet() {
+		dst.Set(target)
+	}
+	for i := 0; i < l; i++ {
+		srcValue := src.Index(i)
+		if srcValue.Kind() == reflect.Ptr || srcValue.Kind() == reflect.Interface {
+			srcValue = srcValue.Elem()
+		}
+		if f, ok := mapHandlers[srcValue.Kind()]; ok {
+			err := f(srcValue, dst.Index(i))
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+func convertMap(src reflect.Value, dst reflect.Value) error {
+	if src.Kind() != reflect.Map || dst.Kind() != reflect.Struct {
+		if src.Kind() == reflect.Interface {
+			return convertMap(src.Elem(), dst)
+		} else {
+			return fmt.Errorf("src or dst type error,%s,%s", src.Type().String(), dst.Type().String())
+		}
+	}
+	dstType := dst.Type()
+	num := dstType.NumField()
+	exist := map[string]int{}
+	for i := 0; i < num; i++ {
+		k := dstType.Field(i).Tag.Get("json")
+		if k == "" {
+			k = dstType.Field(i).Name
+		}
+		if strings.Contains(k, ",") {
+			taglist := strings.Split(k, ",")
+			if taglist[0] == "" {
+
+				k = dstType.Field(i).Name
+			} else {
+				k = taglist[0]
+
+			}
+
+		}
+		exist[k] = i
+	}
+
+	keys := src.MapKeys()
+	for _, key := range keys {
+		if index, ok := exist[key.String()]; ok {
+			v := dst.Field(index)
+			if v.Kind() == reflect.Struct {
+				err := convertMap(src.MapIndex(key), v)
+				if err != nil {
+					return err
+				}
+			} else {
+				if v.CanSet() {
+					if v.Type() == src.MapIndex(key).Elem().Type() {
+						v.Set(src.MapIndex(key).Elem())
+					} else if src.MapIndex(key).Elem().CanConvert(v.Type()) {
+						v.Set(src.MapIndex(key).Elem().Convert(v.Type()))
+					} else if f, ok := mapHandlers[src.MapIndex(key).Elem().Kind()]; ok && f != nil {
+						err := f(src.MapIndex(key).Elem(), v)
+						if err != nil {
+							return err
+						}
+					} else {
+						return fmt.Errorf("error type:d(%s)s(%s)", v.Type(), src.Type())
+					}
+				}
+			}
+		}
+	}
+
+	return nil
+}

maputil/typemap_test.go

@@ -0,0 +1,111 @@
+package maputil
+
+import (
+	"testing"
+
+	"github.com/duke-git/lancet/v2/internal"
+)
+
+type (
+	Person struct {
+		Name  string  `json:"name"`
+		Age   int     `json:"age"`
+		Phone string  `json:"phone"`
+		Addr  Address `json:"address"`
+	}
+
+	Address struct {
+		Street string `json:"street"`
+		Number int    `json:"number"`
+	}
+)
+
+func TestStructType(t *testing.T) {
+	assert := internal.NewAssert(t, "TestStructType")
+
+	src := map[string]interface{}{
+		"name":  "Nothin",
+		"age":   28,
+		"phone": "123456789",
+		"address": map[string]interface{}{
+			"street": "test",
+			"number": 1,
+		},
+	}
+
+	var p Person
+	err := MapTo(src, &p)
+	assert.IsNil(err)
+	assert.Equal(src["name"], p.Name)
+	assert.Equal(src["age"], p.Age)
+	assert.Equal(src["phone"], p.Phone)
+	assert.Equal("test", p.Addr.Street)
+	assert.Equal(1, p.Addr.Number)
+}
+
+func TestBaseType(t *testing.T) {
+	assert := internal.NewAssert(t, "TestBaseType")
+
+	tc := map[string]interface{}{
+		"i32":     -32,
+		"i8":      -8,
+		"i16":     -16,
+		"i64":     -64,
+		"i":       -1,
+		"u32":     32,
+		"u8":      8,
+		"u16":     16,
+		"u64":     64,
+		"u":       1,
+		"tf":      true,
+		"f32":     1.32,
+		"f64":     1.64,
+		"str":     "hello mapto",
+		"complex": 1 + 3i,
+	}
+
+	type BaseType struct {
+		I    int        `json:"i"`
+		I8   int8       `json:"i8"`
+		I16  int16      `json:"i16"`
+		I32  int32      `json:"i32"`
+		I64  int64      `json:"i64"`
+		U    uint       `json:"u"`
+		U8   uint8      `json:"u8"`
+		U16  uint16     `json:"u16"`
+		U32  uint32     `json:"u32"`
+		U64  uint64     `json:"u64"`
+		F32  float32    `json:"f32"`
+		F64  float64    `json:"f64"`
+		Tf   bool       `json:"tf"`
+		Str  string     `json:"str"`
+		Comp complex128 `json:"complex"`
+	}
+
+	var dist BaseType
+	err := MapTo(tc, &dist)
+	assert.IsNil(err)
+
+	var number float64
+
+	MapTo(tc["i"], &number)
+	assert.EqualValues(-1, number)
+	MapTo(tc["i8"], &number)
+	assert.EqualValues(-8, number)
+	MapTo(tc["i16"], &number)
+	assert.EqualValues(-16, number)
+	MapTo(tc["i32"], &number)
+	assert.EqualValues(-32, number)
+	MapTo(tc["i64"], &number)
+	assert.EqualValues(-64, number)
+	MapTo(tc["u"], &number)
+	assert.EqualValues(1, number)
+	MapTo(tc["u8"], &number)
+	assert.EqualValues(8, number)
+	MapTo(tc["u16"], &number)
+	assert.EqualValues(16, number)
+	MapTo(tc["u32"], &number)
+	assert.EqualValues(32, number)
+	MapTo(tc["u64"], &number)
+	assert.EqualValues(64, number)
+}