github.com/gogf/gf/v2@v2.7.4/util/gvalid/internal/builtin/builtin_required.go (about)

     1  // Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
     2  //
     3  // This Source Code Form is subject to the terms of the MIT License.
     4  // If a copy of the MIT was not distributed with this file,
     5  // You can obtain one at https://github.com/gogf/gf.
     6  
     7  package builtin
     8  
     9  import (
    10  	"errors"
    11  	"reflect"
    12  
    13  	"github.com/gogf/gf/v2/util/gconv"
    14  )
    15  
    16  // RuleRequired implements `required` rule.
    17  // Format: required
    18  type RuleRequired struct{}
    19  
    20  func init() {
    21  	Register(RuleRequired{})
    22  }
    23  
    24  func (r RuleRequired) Name() string {
    25  	return "required"
    26  }
    27  
    28  func (r RuleRequired) Message() string {
    29  	return "The {field} field is required"
    30  }
    31  
    32  func (r RuleRequired) Run(in RunInput) error {
    33  	if isRequiredEmpty(in.Value.Val()) {
    34  		return errors.New(in.Message)
    35  	}
    36  	return nil
    37  }
    38  
    39  // isRequiredEmpty checks and returns whether given value is empty string.
    40  // Note that if given value is a zero integer, it will be considered as not empty.
    41  func isRequiredEmpty(value interface{}) bool {
    42  	reflectValue := reflect.ValueOf(value)
    43  	for reflectValue.Kind() == reflect.Ptr {
    44  		reflectValue = reflectValue.Elem()
    45  	}
    46  	switch reflectValue.Kind() {
    47  	case reflect.String, reflect.Map, reflect.Array, reflect.Slice:
    48  		return reflectValue.Len() == 0
    49  	}
    50  	return gconv.String(value) == ""
    51  }