DateTime::Format::Mail - Convert between DateTime and RFC2822/822 formats
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"
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:
As a future direction, I'm contemplating an even stricter parser that will only accept dates with no obsolete elements.
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.
looseshould be a true value if you want a loose parser, else either don't specify it or give it a false value.
year_cutoffshould 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 );
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();
These methods work on either our objects or as class methods.
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;
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.
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 );
Returns the current cutoff. Can be used as either a class or object method.
my $cutoff = $parser->set_year_cutoff;
Returns the default cutoff. A useful method to override for subclasses.
my $default = $parser->default_cutoff;
Takes a year and returns it normalized.
my $fixed = $parser->fix_year( 3 );
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";
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 for this module is provided via the email@example.com 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:
This makes it much easier for me to track things and thus means your problem is less likely to be neglected.
Copyright © 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.
Iain Truskett <firstname.lastname@example.org>
email@example.com mailing list.
RFCs 2822 and 822.