gf/util/gconv/gconv_structs.go

134 lines
4.2 KiB
Go

// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.
package gconv
import (
"reflect"
"github.com/gogf/gf/v2/errors/gcode"
"github.com/gogf/gf/v2/errors/gerror"
)
// Structs converts any slice to given struct slice.
// Also see Scan, Struct.
func Structs(params interface{}, pointer interface{}, paramKeyToAttrMap ...map[string]string) (err error) {
return Scan(params, pointer, paramKeyToAttrMap...)
}
// SliceStruct is alias of Structs.
func SliceStruct(params interface{}, pointer interface{}, mapping ...map[string]string) (err error) {
return Structs(params, pointer, mapping...)
}
// StructsTag acts as Structs but also with support for priority tag feature, which retrieves the
// specified tags for `params` key-value items to struct attribute names mapping.
// The parameter `priorityTag` supports multiple tags that can be joined with char ','.
func StructsTag(params interface{}, pointer interface{}, priorityTag string) (err error) {
return doStructs(params, pointer, nil, priorityTag)
}
// doStructs converts any slice to given struct slice.
//
// It automatically checks and converts json string to []map if `params` is string/[]byte.
//
// The parameter `pointer` should be type of pointer to slice of struct.
// Note that if `pointer` is a pointer to another pointer of type of slice of struct,
// it will create the struct/pointer internally.
func doStructs(
params interface{}, pointer interface{}, paramKeyToAttrMap map[string]string, priorityTag string,
) (err error) {
defer func() {
// Catch the panic, especially the reflection operation panics.
if exception := recover(); exception != nil {
if v, ok := exception.(error); ok && gerror.HasStack(v) {
err = v
} else {
err = gerror.NewCodeSkipf(gcode.CodeInternalPanic, 1, "%+v", exception)
}
}
}()
// Pointer type check.
pointerRv, ok := pointer.(reflect.Value)
if !ok {
pointerRv = reflect.ValueOf(pointer)
if kind := pointerRv.Kind(); kind != reflect.Ptr {
return gerror.NewCodef(
gcode.CodeInvalidParameter,
"pointer should be type of pointer, but got: %v", kind,
)
}
}
// Converting `params` to map slice.
var (
paramsList []interface{}
paramsRv = reflect.ValueOf(params)
paramsKind = paramsRv.Kind()
)
for paramsKind == reflect.Ptr {
paramsRv = paramsRv.Elem()
paramsKind = paramsRv.Kind()
}
switch paramsKind {
case reflect.Slice, reflect.Array:
paramsList = make([]interface{}, paramsRv.Len())
for i := 0; i < paramsRv.Len(); i++ {
paramsList[i] = paramsRv.Index(i).Interface()
}
default:
var paramsMaps = Maps(params)
paramsList = make([]interface{}, len(paramsMaps))
for i := 0; i < len(paramsMaps); i++ {
paramsList[i] = paramsMaps[i]
}
}
// If `params` is an empty slice, no conversion.
if len(paramsList) == 0 {
return nil
}
var (
reflectElemArray = reflect.MakeSlice(pointerRv.Type().Elem(), len(paramsList), len(paramsList))
itemType = reflectElemArray.Index(0).Type()
itemTypeKind = itemType.Kind()
pointerRvElem = pointerRv.Elem()
pointerRvLength = pointerRvElem.Len()
)
if itemTypeKind == reflect.Ptr {
// Pointer element.
for i := 0; i < len(paramsList); i++ {
var tempReflectValue reflect.Value
if i < pointerRvLength {
// Might be nil.
tempReflectValue = pointerRvElem.Index(i).Elem()
}
if !tempReflectValue.IsValid() {
tempReflectValue = reflect.New(itemType.Elem()).Elem()
}
if err = doStruct(paramsList[i], tempReflectValue, paramKeyToAttrMap, priorityTag); err != nil {
return err
}
reflectElemArray.Index(i).Set(tempReflectValue.Addr())
}
} else {
// Struct element.
for i := 0; i < len(paramsList); i++ {
var tempReflectValue reflect.Value
if i < pointerRvLength {
tempReflectValue = pointerRvElem.Index(i)
} else {
tempReflectValue = reflect.New(itemType).Elem()
}
if err = doStruct(paramsList[i], tempReflectValue, paramKeyToAttrMap, priorityTag); err != nil {
return err
}
reflectElemArray.Index(i).Set(tempReflectValue)
}
}
pointerRv.Elem().Set(reflectElemArray)
return nil
}