NAME¶
DateTime::Format::Mail - Convert between DateTime and RFC2822/822 formats
SYNOPSIS¶
use DateTime::Format::Mail;
# From RFC2822 via class method:
my $datetime = DateTime::Format::Mail->parse_datetime(
"Sat, 29 Mar 2003 22:11:18 -0800"
);
print $datetime->ymd('.'); # "2003.03.29"
# or via an object
my $pf = DateTime::Format::Mail->new();
print $pf->parse_datetime(
"Fri, 23 Nov 2001 21:57:24 -0600"
)->ymd; # "2001-11-23"
# Back to RFC2822 date
use DateTime;
my $dt = DateTime->new(
year => 1979, month => 7, day => 16,
hour => 16, minute => 45, second => 20,
time_zone => "Australia/Sydney"
);
my $str = DateTime::Format::Mail->format_datetime( $dt );
print $str; # "Mon, 16 Jul 1979 16:45:20 +1000"
# or via an object
$str = $pf->format_datetime( $dt );
print $str; # "Mon, 16 Jul 1979 16:45:20 +1000"
DESCRIPTION¶
RFCs 2822 and 822 specify date formats to be used by email. This module parses
and emits such dates.
RFC2822 (April 2001) introduces a slightly different format of date than that
used by RFC822 (August 1982). The main correction is that the preferred format
is more limited, and thus easier to parse programmatically.
Despite the ease of generating and parsing perfectly valid RFC822 and RFC2822
people still get it wrong. So this module provides four things for those
handling mail dates:
- 1.
- A strict parser that will only accept RFC2822 dates, so you can see where
you're right.
- 2.
- A strict formatter, so you can generate the right stuff to begin
with.
- 3.
- A loose parser, so you can take the misbegotten output from other
programs and turn it into something useful. This includes various minor
errors as well as some somewhat more bizarre mistakes. The file
t/sample_dates in this module's distribution should give you an
idea of what's valid, while t/invalid.t should do the same for
what's not. Those regarded as invalid are just a bit too strange to
allow.
- 4.
- Interoperation with the rest of the DateTime suite. These are a collection
of modules to handle dates in a modern and accurate fashion. In
particular, they make it trivial to parse, manipulate and then format
dates. Shifting timezones is a doddle, and converting between formats is a
cinch.
As a future direction, I'm contemplating an even stricter parser that will only
accept dates with no obsolete elements.
CONSTRUCTORS¶
new¶
Creates a new "DateTime::Format::Mail" instance. This is generally not
required for simple operations. If you wish to use a different parsing style
from the default, strict, parser then you'll need to create an object.
my $parser = DateTime::Format::Mail->new()
my $copy = $parser->new();
If called on an existing object then it clones the object.
It has two optional named parameters.
- •
- "loose" should be a true value if you want a loose parser, else
either don't specify it or give it a false value.
- •
- "year_cutoff" should be an integer greater than or equal to zero
specifying the cutoff year. See "set_year_cutoff" for
details.
my $loose = DateTime::Format::Mail->new( loose => 1 );
my $post_2049 = DateTime::Format::Mail->new(
year_cutoff => 60
);
clone¶
For those who prefer to explicitly clone via a method called
"clone()". If called as a class method it will die.
my $clone = $original->clone();
PARSING METHODS¶
These methods work on either our objects or as class methods.
loose, strict¶
These methods set the parsing strictness.
my $parser = DateTime::Format::Mail->new;
$parser->loose;
$parser->strict; # (the default)
my $p = DateTime::Format::Mail->new->loose;
parse_datetime¶
Given an RFC2822 or 822 datetime string, return a "DateTime" object
representing that date and time. Unparseable strings will cause the method to
die.
See the synopsis for examples.
set_year_cutoff¶
Two digit years are treated as valid in the loose translation and are translated
up to a 19xx or 20xx figure. By default, following the specification of
RFC2822, if the year is greater than '49', it's treated as being in the 20th
century (19xx). If lower, or equal, then the 21st (20xx). That is, 50 becomes
1950 while 49 is 2049.
"set_year_cutoff()" allows you to modify this behaviour by specifying
a different cutoff.
The return value is the object itself.
$parser->set_year_cutoff( 60 );
year_cutoff¶
Returns the current cutoff. Can be used as either a class or object method.
my $cutoff = $parser->set_year_cutoff;
default_cutoff¶
Returns the default cutoff. A useful method to override for subclasses.
my $default = $parser->default_cutoff;
fix_year¶
Takes a year and returns it normalized.
my $fixed = $parser->fix_year( 3 );
Given a "DateTime" object, return it as an RFC2822 compliant string.
use DateTime;
use DateTime::Format::Mail;
my $dt = DateTime->new(
year => 1979, month => 7, day => 16, time_zone => 'UTC'
);
my $mail = DateTime::Format::Mail->format_datetime( $dt );
print $mail, "\n";
# or via an object
my $formatter = DateTime::Format::Mail->new();
my $rfcdate = $formatter->format_datetime( $dt );
print $rfcdate, "\n";
THANKS FROM SPOON¶
Dave Rolsky (DROLSKY) for kickstarting the DateTime project.
Roderick A. Anderson for noting where the documentation was incomplete in
places.
Joshua Hoblitt (JHOBLITT) for inspiring me to check what the standard said about
interpreting two digit years.
SUPPORT¶
Support for this module is provided via the datetime@perl.org email list. See
<
http://datetime.perl.org/mailing_list.html> for more details.
Alternatively, log them via the CPAN RT system via the web or email:
http://rt.cpan.org/NoAuth/ReportBug.html?Queue=DateTime-Format-Mail
bug-datetime-format-mail@rt.cpan.org
This makes it much easier for me to track things and thus means your problem is
less likely to be neglected.
LICENCE AND COPYRIGHT¶
Copyright X Iain Truskett, 2003. All rights reserved.
This library is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.
The full text of the licences can be found in the
LICENSE file included
with this module, or in perlartistic and perlgpl in Perl 5.8.1 or later.
AUTHORS¶
Originally written by Iain Truskett <spoon@cpan.org>, who died on December
29, 2003.
Maintained by Dave Rolsky <autarch@urth.org> from 2003 to 2013.
Maintained by Philippe Bruhat (BooK) <book@cpan.org> since 2014.
SEE ALSO¶
"datetime@perl.org" mailing list.
<
http://datetime.perl.org/>
perl, DateTime
RFCs 2822 and 822.