niki/vendor/github.com/go-ozzo/ozzo-validation/v4/string.go

65 lines
1.9 KiB
Go

// Copyright 2016 Qiang Xue. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package validation
type stringValidator func(string) bool
// StringRule is a rule that checks a string variable using a specified stringValidator.
type StringRule struct {
validate stringValidator
err Error
}
// NewStringRule creates a new validation rule using a function that takes a string value and returns a bool.
// The rule returned will use the function to check if a given string or byte slice is valid or not.
// An empty value is considered to be valid. Please use the Required rule to make sure a value is not empty.
func NewStringRule(validator stringValidator, message string) StringRule {
return StringRule{
validate: validator,
err: NewError("", message),
}
}
// NewStringRuleWithError creates a new validation rule using a function that takes a string value and returns a bool.
// The rule returned will use the function to check if a given string or byte slice is valid or not.
// An empty value is considered to be valid. Please use the Required rule to make sure a value is not empty.
func NewStringRuleWithError(validator stringValidator, err Error) StringRule {
return StringRule{
validate: validator,
err: err,
}
}
// Error sets the error message for the rule.
func (r StringRule) Error(message string) StringRule {
r.err = r.err.SetMessage(message)
return r
}
// ErrorObject sets the error struct for the rule.
func (r StringRule) ErrorObject(err Error) StringRule {
r.err = err
return r
}
// Validate checks if the given value is valid or not.
func (r StringRule) Validate(value interface{}) error {
value, isNil := Indirect(value)
if isNil || IsEmpty(value) {
return nil
}
str, err := EnsureString(value)
if err != nil {
return err
}
if r.validate(str) {
return nil
}
return r.err
}