File Coverage

blib/lib/Plack/Middleware/HTTPExceptions.pm

Criterion	Covered	Total	%
statement	53	58	91.3
branch	14	20	70.0
condition	9	14	64.2
subroutine	13	13	100.0
pod	2	3	66.6
total	91	108	84.2

package Plack::Middleware::HTTPExceptions;
use strict;
use parent qw(Plack::Middleware);
use Plack::Util::Accessor qw(rethrow);

use Carp ();
use Try::Tiny;
use Scalar::Util 'blessed';
use HTTP::Status ();

sub prepare_app {
    my $self = shift;
    $self->rethrow(1) if ($ENV{PLACK_ENV} || '') eq 'development';
}

sub call {
    my($self, $env) = @_;

    my $res = try {
        $self->app->($env);
    } catch {
        $self->transform_error($_, $env);
    };

    return $res if ref $res eq 'ARRAY';

    return sub {
        my $respond = shift;

        my $writer;
        try {
            $res->(sub { return $writer = $respond->(@_) });
        } catch {
            if ($writer) {
                Carp::cluck $_;
                $writer->close;
            } else {
                my $res = $self->transform_error($_, $env);
                $respond->($res);
            }
        };
    };
}

sub transform_error {
    my($self, $e, $env) = @_;

    my($code, $message);
    if (blessed $e && $e->can('as_psgi')) {
        return $e->as_psgi;
    }
    if (blessed $e && $e->can('code')) {
        $code = $e->code;
        $message =
            $e->can('as_string')       ? $e->as_string :
            overload::Method($e, '""') ? "$e"          : undef;
    } else {
        if ($self->rethrow) {
            die $e;
        }
        else {
            $code = 500;
            $env->{'psgi.errors'}->print($e);
        }
    }

    if ($code !~ /^[3-5]\d\d$/) {
        die $e; # rethrow
    }

    $message ||= HTTP::Status::status_message($code);

    my @headers = (
         'Content-Type'   => 'text/plain',
         'Content-Length' => length($message),
    );

    if ($code =~ /^3/ && (my $loc = eval { $e->location })) {
        push(@headers, Location => $loc);
    }

    return [ $code, \@headers, [ $message ] ];
}

1;

__END__