README.md
1# NAME
2
3HTTP::Date - HTTP::Date - date conversion routines
4
5# VERSION
6
7version 6.05
8
9# SYNOPSIS
10
11 use HTTP::Date;
12
13 $string = time2str($time); # Format as GMT ASCII time
14 $time = str2time($string); # convert ASCII date to machine time
15
16# DESCRIPTION
17
18This module provides functions that deal the date formats used by the
19HTTP protocol (and then some more). Only the first two functions,
20time2str() and str2time(), are exported by default.
21
22- time2str( \[$time\] )
23
24 The time2str() function converts a machine time (seconds since epoch)
25 to a string. If the function is called without an argument or with an
26 undefined argument, it will use the current time.
27
28 The string returned is in the format preferred for the HTTP protocol.
29 This is a fixed length subset of the format defined by RFC 1123,
30 represented in Universal Time (GMT). An example of a time stamp
31 in this format is:
32
33 Sun, 06 Nov 1994 08:49:37 GMT
34
35- str2time( $str \[, $zone\] )
36
37 The str2time() function converts a string to machine time. It returns
38 `undef` if the format of $str is unrecognized, otherwise whatever the
39 `Time::Local` functions can make out of the parsed time. Dates
40 before the system's epoch may not work on all operating systems. The
41 time formats recognized are the same as for parse\_date().
42
43 The function also takes an optional second argument that specifies the
44 default time zone to use when converting the date. This parameter is
45 ignored if the zone is found in the date string itself. If this
46 parameter is missing, and the date string format does not contain any
47 zone specification, then the local time zone is assumed.
48
49 If the zone is not "`GMT`" or numerical (like "`-0800`" or
50 "`+0100`"), then the `Time::Zone` module must be installed in order
51 to get the date recognized.
52
53- parse\_date( $str )
54
55 This function will try to parse a date string, and then return it as a
56 list of numerical values followed by a (possible undefined) time zone
57 specifier; ($year, $month, $day, $hour, $min, $sec, $tz). The $year
58 will be the full 4-digit year, and $month numbers start with 1 (for January).
59
60 In scalar context the numbers are interpolated in a string of the
61 "YYYY-MM-DD hh:mm:ss TZ"-format and returned.
62
63 If the date is unrecognized, then the empty list is returned (`undef` in
64 scalar context).
65
66 The function is able to parse the following formats:
67
68 "Wed, 09 Feb 1994 22:23:32 GMT" -- HTTP format
69 "Thu Feb 3 17:03:55 GMT 1994" -- ctime(3) format
70 "Thu Feb 3 00:00:00 1994", -- ANSI C asctime() format
71 "Tuesday, 08-Feb-94 14:15:29 GMT" -- old rfc850 HTTP format
72 "Tuesday, 08-Feb-1994 14:15:29 GMT" -- broken rfc850 HTTP format
73
74 "03/Feb/1994:17:03:55 -0700" -- common logfile format
75 "09 Feb 1994 22:23:32 GMT" -- HTTP format (no weekday)
76 "08-Feb-94 14:15:29 GMT" -- rfc850 format (no weekday)
77 "08-Feb-1994 14:15:29 GMT" -- broken rfc850 format (no weekday)
78
79 "1994-02-03 14:15:29 -0100" -- ISO 8601 format
80 "1994-02-03 14:15:29" -- zone is optional
81 "1994-02-03" -- only date
82 "1994-02-03T14:15:29" -- Use T as separator
83 "19940203T141529Z" -- ISO 8601 compact format
84 "19940203" -- only date
85
86 "08-Feb-94" -- old rfc850 HTTP format (no weekday, no time)
87 "08-Feb-1994" -- broken rfc850 HTTP format (no weekday, no time)
88 "09 Feb 1994" -- proposed new HTTP format (no weekday, no time)
89 "03/Feb/1994" -- common logfile format (no time, no offset)
90
91 "Feb 3 1994" -- Unix 'ls -l' format
92 "Feb 3 17:03" -- Unix 'ls -l' format
93
94 "11-15-96 03:52PM" -- Windows 'dir' format
95
96 The parser ignores leading and trailing whitespace. It also allow the
97 seconds to be missing and the month to be numerical in most formats.
98
99 If the year is missing, then we assume that the date is the first
100 matching date _before_ current month. If the year is given with only
101 2 digits, then parse\_date() will select the century that makes the
102 year closest to the current date.
103
104- time2iso( \[$time\] )
105
106 Same as time2str(), but returns a "YYYY-MM-DD hh:mm:ss"-formatted
107 string representing time in the local time zone.
108
109- time2isoz( \[$time\] )
110
111 Same as time2str(), but returns a "YYYY-MM-DD hh:mm:ssZ"-formatted
112 string representing Universal Time.
113
114# SEE ALSO
115
116["time" in perlfunc](https://metacpan.org/pod/perlfunc#time), [Time::Zone](https://metacpan.org/pod/Time::Zone)
117
118# AUTHOR
119
120Gisle Aas <gisle@activestate.com>
121
122# COPYRIGHT AND LICENSE
123
124This software is copyright (c) 1995-2019 by Gisle Aas.
125
126This is free software; you can redistribute it and/or modify it under
127the same terms as the Perl 5 programming language system itself.
128