gin/binding/default_validator.go

96 lines
2.3 KiB
Go

// Copyright 2017 Manu Martinez-Almeida. All rights reserved.
// Use of this source code is governed by a MIT style
// license that can be found in the LICENSE file.
package binding
import (
"reflect"
"strconv"
"strings"
"sync"
"github.com/go-playground/validator/v10"
)
type defaultValidator struct {
once sync.Once
validate *validator.Validate
}
type SliceValidationError []error
// Error concatenates all error elements in SliceValidationError into a single string separated by \n.
func (err SliceValidationError) Error() string {
if len(err) == 0 {
return ""
}
var b strings.Builder
for i := 0; i < len(err); i++ {
if err[i] != nil {
if b.Len() > 0 {
b.WriteString("\n")
}
b.WriteString("[" + strconv.Itoa(i) + "]: " + err[i].Error())
}
}
return b.String()
}
var _ StructValidator = (*defaultValidator)(nil)
// ValidateStruct receives any kind of type, but only performed struct or pointer to struct type.
func (v *defaultValidator) ValidateStruct(obj any) error {
if obj == nil {
return nil
}
value := reflect.ValueOf(obj)
switch value.Kind() {
case reflect.Ptr:
if value.Elem().Kind() != reflect.Struct {
return v.ValidateStruct(value.Elem().Interface())
}
return v.validateStruct(obj)
case reflect.Struct:
return v.validateStruct(obj)
case reflect.Slice, reflect.Array:
count := value.Len()
validateRet := make(SliceValidationError, 0)
for i := 0; i < count; i++ {
if err := v.ValidateStruct(value.Index(i).Interface()); err != nil {
validateRet = append(validateRet, err)
}
}
if len(validateRet) == 0 {
return nil
}
return validateRet
default:
return nil
}
}
// validateStruct receives struct type
func (v *defaultValidator) validateStruct(obj any) error {
v.lazyinit()
return v.validate.Struct(obj)
}
// Engine returns the underlying validator engine which powers the default
// Validator instance. This is useful if you want to register custom validations
// or struct level validations. See validator GoDoc for more info -
// https://pkg.go.dev/github.com/go-playground/validator/v10
func (v *defaultValidator) Engine() any {
v.lazyinit()
return v.validate
}
func (v *defaultValidator) lazyinit() {
v.once.Do(func() {
v.validate = validator.New()
v.validate.SetTagName("binding")
})
}