File Coverage

blib/lib/Dancer2/Plugin/Deferred.pm

Criterion	Covered	Total	%
statement	56	59	94.9
branch	8	12	66.6
condition	8	10	80.0
subroutine	15	15	100.0
pod	3	4	75.0
total	90	100	90.0

use 5.008001;
use strict;
use warnings;

package Dancer2::Plugin::Deferred;
our $AUTHORITY = 'cpan:YANICK';
$Dancer2::Plugin::Deferred::VERSION = '0.007017';
# ABSTRACT: Defer messages or data across redirections
# VERSION

use Dancer2::Core::Types qw/Str/;
use URI;
use URI::QueryParam;

use Dancer2::Plugin 0.200000;

has var_key => (
    is => 'ro',
    isa => Str,
    from_config => sub { 'dpdid' },
);

has var_keep_key => (
    is => 'ro',
    isa => Str,
    from_config => sub { 'dpd_keep' },
);

has params_key => (
    is => 'ro',
    isa => Str,
    from_config => sub { 'dpdid' },
);

has session_key_prefix => (
    is => 'ro',
    isa => Str,
    from_config => sub { 'dpd_' },
);

has template_key => (
    is => 'ro',
    isa => Str,
    from_config => sub { 'deferred' },
);

plugin_keywords 'deferred', 'all_deferred', 'deferred_param';

sub deferred {
    my ( $plugin, $key, $value ) = @_;
    my $app = $plugin->app;

    my $id = $plugin->_get_id;

    # message data is flat "dpd_$id" to avoid race condition with
    # another session
    my $data = $app->session->read(  $plugin->session_key_prefix . $id ) || {};

    # set value or destructively retrieve it
    if ( defined $value ) {
        $data->{$key} = $value;
    }
    else {
        $value =
            $app->request->var( $plugin->var_keep_key )
          ? $data->{$key}
          : delete $data->{$key};
    }

    # store remaining data or clear it if no deferred messages are left
    if ( keys %$data ) {
        $app->session->write( $plugin->session_key_prefix . $id => $data );
        $app->request->var( $plugin->var_key => $id );
    }
    else {
        $app->session->delete( $plugin->session_key_prefix . $id );
        $app->request->var( $plugin->var_key => undef );
    }
    return $value;
};

sub all_deferred {
    my $plugin = shift;
    my $app = $plugin->app;

    my $id = $plugin->_get_id;
    my $data = $plugin->app->session->read( $plugin->session_key_prefix . $id ) || {};

    unless ( $app->request->var( $plugin->var_keep_key ) ) {
        $app->session->delete( $plugin->session_key_prefix . $id );
        $app->request->var( $plugin->var_key, undef );
    }
    return $data;
}

sub deferred_param {
    my $plugin = shift;

    $plugin->app->request->var( $plugin->var_keep_key => 1 );

    return ( $plugin->params_key => $plugin->app->request->var( $plugin->var_key ) );
}

# not crypto strong, but will be stored in session, which should be
sub _get_id {
    my $plugin = shift;

    return $plugin->app->request->var( $plugin->var_key )
      || sprintf( "%08d", int( rand(100_000_000) ) );
}

sub BUILD {
    my $plugin = shift;

    $plugin->app->add_hook(
        Dancer2::Core::Hook->new(
            name => 'before_template',
            code => sub {
                my $data = shift;
                $data->{$plugin->template_key} = $plugin->all_deferred;
            }
        )
    );

    $plugin->app->add_hook(
        Dancer2::Core::Hook->new(
            name => 'before',
            code => sub {
                my $id = $plugin->app->request->params->{ $plugin->params_key };
                $plugin->app->request->var( $plugin->var_key => $id )
                  if $id;
            }
        )
    );

    $plugin->app->add_hook(
        Dancer2::Core::Hook->new(
            name => 'after',
            code => sub {
                my $response = shift;
                if (   $plugin->app->request->var( $plugin->var_key )
                    && $response->status =~ /^3/ )
                {
                    my $u = URI->new( $response->header("Location") );
                    $u->query_param( $plugin->deferred_param );
                    $response->header( "Location" => $u );
                }
            }
        )
    );
};

1;


# vim: ts=4 sts=4 sw=4 et:

__END__