1 // Copyright 2016 Qiang Xue. All rights reserved.
2 // Use of this source code is governed by a MIT-style
3 // license that can be found in the LICENSE file.
4 5 package validation
6 7 import (
8 "time"
9 )
10 11 var (
12 // ErrDateInvalid is the error that returns in case of an invalid date.
13 ErrDateInvalid = NewError("validation_date_invalid", "must be a valid date")
14 // ErrDateOutOfRange is the error that returns in case of an invalid date.
15 ErrDateOutOfRange = NewError("validation_date_out_of_range", "the date is out of range")
16 )
17 18 // DateRule is a validation rule that validates date/time string values.
19 type DateRule struct {
20 layout string
21 min, max time.Time
22 err, rangeErr Error
23 }
24 25 // Date returns a validation rule that checks if a string value is in a format that can be parsed into a date.
26 // The format of the date should be specified as the layout parameter which accepts the same value as that for time.Parse.
27 // For example,
28 // validation.Date(time.ANSIC)
29 // validation.Date("02 Jan 06 15:04 MST")
30 // validation.Date("2006-01-02")
31 //
32 // By calling Min() and/or Max(), you can let the Date rule to check if a parsed date value is within
33 // the specified date range.
34 //
35 // An empty value is considered valid. Use the Required rule to make sure a value is not empty.
36 func Date(layout string) DateRule {
37 return DateRule{
38 layout: layout,
39 err: ErrDateInvalid,
40 rangeErr: ErrDateOutOfRange,
41 }
42 }
43 44 // Error sets the error message that is used when the value being validated is not a valid date.
45 func (r DateRule) Error(message string) DateRule {
46 r.err = r.err.SetMessage(message)
47 return r
48 }
49 50 // ErrorObject sets the error struct that is used when the value being validated is not a valid date..
51 func (r DateRule) ErrorObject(err Error) DateRule {
52 r.err = err
53 return r
54 }
55 56 // RangeError sets the error message that is used when the value being validated is out of the specified Min/Max date range.
57 func (r DateRule) RangeError(message string) DateRule {
58 r.rangeErr = r.rangeErr.SetMessage(message)
59 return r
60 }
61 62 // RangeErrorObject sets the error struct that is used when the value being validated is out of the specified Min/Max date range.
63 func (r DateRule) RangeErrorObject(err Error) DateRule {
64 r.rangeErr = err
65 return r
66 }
67 68 // Min sets the minimum date range. A zero value means skipping the minimum range validation.
69 func (r DateRule) Min(min time.Time) DateRule {
70 r.min = min
71 return r
72 }
73 74 // Max sets the maximum date range. A zero value means skipping the maximum range validation.
75 func (r DateRule) Max(max time.Time) DateRule {
76 r.max = max
77 return r
78 }
79 80 // Validate checks if the given value is a valid date.
81 func (r DateRule) Validate(value interface{}) error {
82 value, isNil := Indirect(value)
83 if isNil || IsEmpty(value) {
84 return nil
85 }
86 87 str, err := EnsureString(value)
88 if err != nil {
89 return err
90 }
91 92 date, err := time.Parse(r.layout, str)
93 if err != nil {
94 return r.err
95 }
96 97 if !r.min.IsZero() && r.min.After(date) || !r.max.IsZero() && date.After(r.max) {
98 return r.rangeErr
99 }
100 101 return nil
102 }
103