File Coverage

blib/lib/Plack/Middleware/NeverExpire.pm

Criterion	Covered	Total	%
statement	23	23	100.0
branch	2	4	50.0
condition			n/a
subroutine	8	8	100.0
pod	3	3	100.0
total	36	38	94.7

use 5.008001; use strict; use warnings;

package Plack::Middleware::NeverExpire;

our $VERSION = '1.201';

BEGIN { require Plack::Middleware; our @ISA = 'Plack::Middleware' }

use Plack::Util ();

sub ONE_YEAR () { 31_556_930 } # 365.24225 days

# RFC 9110 Section 5.6.7
my @DAY = qw( Sun Mon Tue Wed Thu Fri Sat );
my @MON = qw( Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec );
sub FMT () { '%s, %02d %s %04d %02d:%02d:%02d GMT' }
sub imf_fixdate {
	my @f = gmtime $_[0];
	sprintf FMT, $DAY[$f[6]], $f[3], $MON[$f[4]], 1900+$f[5], @f[2,1,0];
}

my $cached_stamp = imf_fixdate my $cached_time = time;
sub inject_headers {
	$_[0][0] == 200 or return;
	my $h = $_[0][1];
	push @$h, 'Cache-Control', 'max-age=' . ONE_YEAR . ', public';
	my $now = time;
	$cached_time == $now or $cached_stamp = imf_fixdate ONE_YEAR + ( $cached_time = $now );
	Plack::Util::header_set( $h, Expires => $cached_stamp );
}

sub call { Plack::Util::response_cb( &{ shift->app }, \&inject_headers ) }

1;

__END__