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use Moose;
extends 'Catalyst::Engine';
has _header_buf => (is => 'rw', clearer => '_clear_header_buf', predicate => '_has_header_buf');
=head1 NAME
Catalyst::Engine::CGI - The CGI Engine
=head1 SYNOPSIS
A script using the Catalyst::Engine::CGI module might look like:
#!/usr/bin/perl -w
use strict;
use lib '/path/to/MyApp/lib';
use MyApp;
MyApp->run;
The application module (C<MyApp>) would use C<Catalyst>, which loads the
appropriate engine module.
=head1 DESCRIPTION
This is the Catalyst engine specialized for the CGI environment.
=head1 OVERLOADED METHODS
This class overloads some methods from C<Catalyst::Engine>.
=head2 $self->finalize_headers($c)
=cut
sub finalize_headers {
my ( $self, $c ) = @_;
$c->response->header( Status => $c->response->status );
$self->_header_buf($c->response->headers->as_string("\015\012") . "\015\012");
}
=head2 $self->prepare_connection($c)
=cut
sub prepare_connection {
my ( $self, $c ) = @_;
local (*ENV) = $self->env || \%ENV;
my $request = $c->request;
$request->address( $ENV{REMOTE_ADDR} );
PROXY_CHECK:
{
unless ( ref($c)->config->{using_frontend_proxy} ) {
last PROXY_CHECK if $ENV{REMOTE_ADDR} ne '127.0.0.1';
last PROXY_CHECK if ref($c)->config->{ignore_frontend_proxy};
}
last PROXY_CHECK unless $ENV{HTTP_X_FORWARDED_FOR};
# If we are running as a backend server, the user will always appear
# as 127.0.0.1. Select the most recent upstream IP (last in the list)
my ($ip) = $ENV{HTTP_X_FORWARDED_FOR} =~ /([^,\s]+)$/;
$request->address($ip);
if ( defined $ENV{HTTP_X_FORWARDED_PORT} ) {
$ENV{SERVER_PORT} = $ENV{HTTP_X_FORWARDED_PORT};
}
}
$request->hostname( $ENV{REMOTE_HOST} ) if exists $ENV{REMOTE_HOST};
$request->protocol( $ENV{SERVER_PROTOCOL} );
$request->user( $ENV{REMOTE_USER} ); # XXX: Deprecated. See Catalyst::Request for removal information
$request->remote_user( $ENV{REMOTE_USER} );
$request->method( $ENV{REQUEST_METHOD} );
if ( $ENV{HTTPS} && uc( $ENV{HTTPS} ) eq 'ON' ) {
$request->secure(1);
}
if ( $ENV{SERVER_PORT} == 443 ) {
$request->secure(1);
}
binmode(STDOUT); # Ensure we are sending bytes.
}
=head2 $self->prepare_headers($c)
=cut
sub prepare_headers {
my ( $self, $c ) = @_;
local (*ENV) = $self->env || \%ENV;
my $headers = $c->request->headers;
# Read headers from %ENV
foreach my $header ( keys %ENV ) {
next unless $header =~ /^(?:HTTP|CONTENT|COOKIE)/i;
( my $field = $header ) =~ s/^HTTPS?_//;
$headers->header( $field => $ENV{$header} );
}
}
=head2 $self->prepare_path($c)
=cut
# Please don't touch this method without adding tests in
# t/aggregate/unit_core_engine_cgi-prepare_path.t
sub prepare_path {
my ( $self, $c ) = @_;
local (*ENV) = $self->env || \%ENV;
my $scheme = $c->request->secure ? 'https' : 'http';
my $host = $ENV{HTTP_HOST} || $ENV{SERVER_NAME};
my $port = $ENV{SERVER_PORT} || 80;
my $script_name = $ENV{SCRIPT_NAME};
$script_name =~ s/([^$URI::uric])/$URI::Escape::escapes{$1}/go if $script_name;
my $base_path;
if ( exists $ENV{REDIRECT_URL} ) {
$base_path = $ENV{REDIRECT_URL};
$base_path =~ s/$ENV{PATH_INFO}$//;
}
else {
$base_path = $script_name || '/';
}
# If we are running as a backend proxy, get the true hostname
PROXY_CHECK:
{
unless ( ref($c)->config->{using_frontend_proxy} ) {
last PROXY_CHECK if $host !~ /localhost|127.0.0.1/;
last PROXY_CHECK if ref($c)->config->{ignore_frontend_proxy};
}
last PROXY_CHECK unless $ENV{HTTP_X_FORWARDED_HOST};
$host = $ENV{HTTP_X_FORWARDED_HOST};
# backend could be on any port, so
# assume frontend is on the default port
$port = $c->request->secure ? 443 : 80;
if ( $ENV{HTTP_X_FORWARDED_PORT} ) {
$port = $ENV{HTTP_X_FORWARDED_PORT};
}
}
# RFC 3875: "Unlike a URI path, the PATH_INFO is not URL-encoded,
# and cannot contain path-segment parameters." This means PATH_INFO
# is always decoded, and the script can't distinguish / vs %2F.
# Here we try to resurrect the original encoded URI from REQUEST_URI.
my $path_info = $ENV{PATH_INFO};
if (my $req_uri = $ENV{REQUEST_URI}) {
$req_uri =~ s/^\Q$base_path\E//;
$req_uri =~ s/\?.*$//;
if ($req_uri) {
# Note that if REQUEST_URI doesn't start with a /, then the user
# is probably using mod_rewrite or something to rewrite requests
# into a sub-path of their application..
# This means that REQUEST_URI needs information from PATH_INFO
# prepending to it to be useful, otherwise the sub path which is
# being redirected to becomes the app base address which is
# incorrect.
if (substr($req_uri, 0, 1) ne '/') {
my ($match) = $req_uri =~ m|^([^/]+)|;
my ($path_info_part) = $path_info =~ m|^(.*?\Q$match\E)|;
substr($req_uri, 0, length($match), $path_info_part)
if $path_info_part;
}
$path_info = $req_uri;
}
}
# set the request URI
my $path = $base_path . ( $path_info || '' );
$path =~ s{^/+}{};
# Using URI directly is way too slow, so we construct the URLs manually
my $uri_class = "URI::$scheme";
# HTTP_HOST will include the port even if it's 80/443
$host =~ s/:(?:80|443)$//;
if ( $port !~ /^(?:80|443)$/ && $host !~ /:/ ) {
$host .= ":$port";
}
# Escape the path
$path =~ s/([^$URI::uric])/$URI::Escape::escapes{$1}/go;
$path =~ s/\?/%3F/g; # STUPID STUPID SPECIAL CASE
my $query = $ENV{QUERY_STRING} ? '?' . $ENV{QUERY_STRING} : '';
my $uri = $scheme . '://' . $host . '/' . $path . $query;
$c->request->uri( bless(\$uri, $uri_class)->canonical );
# set the base URI
# base must end in a slash
$base_path .= '/' unless $base_path =~ m{/$};
my $base_uri = $scheme . '://' . $host . $base_path;
$c->request->base( bless \$base_uri, $uri_class );
}
=head2 $self->prepare_query_parameters($c)
=cut
around prepare_query_parameters => sub {
my $orig = shift;
my ( $self, $c ) = @_;
local (*ENV) = $self->env || \%ENV;
if ( $ENV{QUERY_STRING} ) {
$self->$orig( $c, $ENV{QUERY_STRING} );
}
};
=head2 $self->prepare_request($c, (env => \%env))
=cut
sub prepare_request {
my ( $self, $c, %args ) = @_;
if ( $args{env} ) {
$self->env( $args{env} );
}
}
=head2 $self->prepare_write($c)
Enable autoflush on the output handle for CGI-based engines.
=cut
around prepare_write => sub {
*STDOUT->autoflush(1);
return shift->(@_);
};
=head2 $self->write($c, $buffer)
Writes the buffer to the client.
=cut
around write => sub {
my $orig = shift;
my ( $self, $c, $buffer ) = @_;
# Prepend the headers if they have not yet been sent
if ( $self->_has_header_buf ) {
$buffer = $self->_clear_header_buf . $buffer;
}
return $self->$orig( $c, $buffer );
};
=head2 $self->read_chunk($c, $buffer, $length)
=cut
sub read_chunk { shift; shift; *STDIN->sysread(@_); }
=head2 $self->run
=cut
sub run { shift; shift->handle_request( env => \%ENV ) }
=head1 SEE ALSO
L<Catalyst>, L<Catalyst::Engine>
=head1 AUTHORS
Catalyst Contributors, see Catalyst.pm
=head1 COPYRIGHT
This library is free software. You can redistribute it and/or modify it under
the same terms as Perl itself.
=cut
no Moose;
1;