42 lines
1.2 KiB
Go
42 lines
1.2 KiB
Go
// Copyright (c) 2023-2024 Onur Cinar.
|
|
// Use of this source code is governed by a MIT-style
|
|
// license that can be found in the LICENSE file.
|
|
// https://github.com/cinar/checker
|
|
|
|
package checker
|
|
|
|
import (
|
|
"fmt"
|
|
"reflect"
|
|
"strconv"
|
|
)
|
|
|
|
// tagMaxLength is the tag of the checker.
|
|
const tagMaxLength = "max-length"
|
|
|
|
// IsMaxLength checks if the length of the given value is less than the given maximum length.
|
|
func IsMaxLength(value interface{}, maxLength int) error {
|
|
return checkMaxLength(reflect.Indirect(reflect.ValueOf(value)), reflect.ValueOf(nil), maxLength)
|
|
}
|
|
|
|
// makeMaxLength makes a checker function for the max length checker.
|
|
func makeMaxLength(config string) CheckFunc {
|
|
maxLength, err := strconv.Atoi(config)
|
|
if err != nil {
|
|
panic("unable to parse max length value")
|
|
}
|
|
|
|
return func(value, parent reflect.Value) error {
|
|
return checkMaxLength(value, parent, maxLength)
|
|
}
|
|
}
|
|
|
|
// checkMaxLength checks if the length of the given value is less than the given maximum length.
|
|
// The function uses the reflect.Value.Len() function to determaxe the length of the value.
|
|
func checkMaxLength(value, _ reflect.Value, maxLength int) error {
|
|
if value.Len() > maxLength {
|
|
return fmt.Errorf("please enter %d characters or less", maxLength-1)
|
|
}
|
|
|
|
return nil
|
|
}
|