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NAME

Catalyst::Response - stores output responding to the current client request

SYNOPSIS

    $res = $c->response;
    $res->body;
    $res->code;
    $res->content_encoding;
    $res->content_length;
    $res->content_type;
    $res->cookies;
    $res->header;
    $res->headers;
    $res->output;
    $res->redirect;
    $res->status;
    $res->write;

DESCRIPTION

This is the Catalyst Response class, which provides methods for responding to the current client request. The appropriate Catalyst::Engine for your environment will turn the Catalyst::Response into a HTTP Response and return it to the client.

METHODS

$res->body( $text | $fh | $iohandle_object )

    $c->response->body('Catalyst rocks!');

Sets or returns the output (text or binary data). If you are returning a large body, you might want to use a IO::Handle type of object (Something that implements the read method in the same fashion), or a filehandle GLOB. Catalyst will write it piece by piece into the response.

When using a IO::Handle type of object and no content length has been already set in the response headers Catalyst will make a reasonable attempt to determine the size of the Handle. Depending on the implementation of your handle object, setting the content length may fail. If it is at all possible for you to determine the content length of your handle object, it is recommended that you set the content length in the response headers yourself, which will be respected and sent by Catalyst in the response.

Please note that the object needs to implement getline, not just read.

Starting from version 5.90060, when using an IO::Handle object, you may want to use Plack::Middleware::XSendfile, to delegate the actual serving to the frontend server. To do so, you need to pass to body an IO object with a path method. This can be achieved in two ways.

Either using Plack::Util:

  my $fh = IO::File->new($file, 'r');
  Plack::Util::set_io_path($fh, $file);

Or using IO::File::WithPath

  my $fh = IO::File::WithPath->new($file, 'r');

And then passing the filehandle to body and setting headers, if needed.

  $c->response->body($fh);
  $c->response->headers->content_type('text/plain');
  $c->response->headers->content_length(-s $file);
  $c->response->headers->last_modified((stat($file))[9]);

Plack::Middleware::XSendfile can be loaded in the application so:

 __PACKAGE__->config(
     psgi_middleware => [
         'XSendfile',
         # other middlewares here...
        ],
 );

Beware that loading the middleware without configuring the webserver to set the request header X-Sendfile-Type to a supported type (X-Accel-Redirect for nginx, X-Sendfile for Apache and Lighttpd), could lead to the disclosure of private paths to malicious clients setting that header.

Nginx needs the additional X-Accel-Mapping header to be set in the webserver configuration, so the middleware will replace the absolute path of the IO object with the internal nginx path. This is also useful to prevent a buggy app to server random files from the filesystem, as it's an internal redirect.

An nginx configuration for FastCGI could look so:

 server {
     server_name example.com;
     root /my/app/root;
     location /private/repo/ {
         internal;
         alias /my/app/repo/;
     }
     location /private/staging/ {
         internal;
         alias /my/app/staging/;
     }
     location @proxy {
         include /etc/nginx/fastcgi_params;
         fastcgi_param SCRIPT_NAME '';
         fastcgi_param PATH_INFO   $fastcgi_script_name;
         fastcgi_param HTTP_X_SENDFILE_TYPE X-Accel-Redirect;
         fastcgi_param HTTP_X_ACCEL_MAPPING /my/app=/private;
         fastcgi_pass  unix:/my/app/run/app.sock;
    }
 }

In the example above, passing filehandles with a local path matching /my/app/staging or /my/app/repo will be served by nginx. Passing paths with other locations will lead to an internal server error.

Setting the body to a filehandle without the path method bypasses the middleware completely.

For Apache and Lighttpd, the mapping doesn't apply and setting the X-Sendfile-Type is enough.

$res->has_body

Predicate which returns true when a body has been set.

$res->code

Alias for $res->status.

$res->content_encoding

Shortcut for $res->headers->content_encoding.

$res->content_length

Shortcut for $res->headers->content_length.

$res->content_type

Shortcut for $res->headers->content_type.

This value is typically set by your view or plugin. For example, Catalyst::Plugin::Static::Simple will guess the mime type based on the file it found, while Catalyst::View::TT defaults to text/html.

$res->cookies

Returns a reference to a hash containing cookies to be set. The keys of the hash are the cookies' names, and their corresponding values are hash references used to construct a CGI::Simple::Cookie object.

    $c->response->cookies->{foo} = { value => '123' };

The keys of the hash reference on the right correspond to the CGI::Simple::Cookie parameters of the same name, except they are used without a leading dash. Possible parameters are:

value
expires
domain
path
secure
httponly

$res->header

Shortcut for $res->headers->header.

$res->headers

Returns an HTTP::Headers object, which can be used to set headers.

    $c->response->headers->header( 'X-Catalyst' => $Catalyst::VERSION );

$res->output

Alias for $res->body.

$res->redirect( $url, $status )

Causes the response to redirect to the specified URL. The default status is 302.

    $c->response->redirect( 'http://slashdot.org' );
    $c->response->redirect( 'http://slashdot.org', 307 );

This is a convenience method that sets the Location header to the redirect destination, and then sets the response status. You will want to return or $c->detach() to interrupt the normal processing flow if you want the redirect to occur straight away.

Note: do not give a relative URL as $url, i.e: one that is not fully qualified (= http://..., etc.) or that starts with a slash (= /path/here). While it may work, it is not guaranteed to do the right thing and is not a standard behaviour. You may opt to use uri_for() or uri_for_action() instead.

$res->location

Sets or returns the HTTP 'Location'.

$res->status

Sets or returns the HTTP status.

    $c->response->status(404);

$res->code is an alias for this, to match HTTP::Response->code.

$res->write( $data )

Writes $data to the output stream.

$res->write_fh

Returns a PSGI $writer object that has two methods, write and close. You can close over this object for asynchronous and nonblocking applications. For example (assuming you are using a supporting server, like Twiggy

    package AsyncExample::Controller::Root;

    use Moose;

    BEGIN { extends 'Catalyst::Controller' }

    sub prepare_cb {
      my $write_fh = pop;
      return sub {
        my $message = shift;
        $write_fh->write("Finishing: $message\n");
        $write_fh->close;
      };
    }

    sub anyevent :Local :Args(0) {
      my ($self, $c) = @_;
      my $cb = $self->prepare_cb($c->res->write_fh);

      my $watcher;
      $watcher = AnyEvent->timer(
        after => 5,
        cb => sub {
          $cb->(scalar localtime);
          undef $watcher; # cancel circular-ref
        });
    }

$res->print( @data )

Prints @data to the output stream, separated by $,. This lets you pass the response object to functions that want to write to an IO::Handle.

$self->finalize_headers($c)

Writes headers to response if not already written

from_psgi_response

Given a PSGI response (either three element ARRAY reference OR coderef expecting a $responder) set the response from it.

Properly supports streaming and delayed response and / or async IO if running under an expected event loop.

Example:

    package MyApp::Web::Controller::Test;

    use base 'Catalyst::Controller';
    use Plack::App::Directory;


    my $app = Plack::App::Directory->new({ root => "/path/to/htdocs" })
      ->to_app;

    sub myaction :Local Args {
      my ($self, $c) = @_;
      $c->res->from_psgi_response($app->($c->req->env));
    }

Please note this does not attempt to map or nest your PSGI application under the Controller and Action namespace or path.

DEMOLISH

Ensures that the response is flushed and closed at the end of the request.

meta

Provided by Moose

AUTHORS

Catalyst Contributors, see Catalyst.pm

COPYRIGHT

This library is free software. You can redistribute it and/or modify it under the same terms as Perl itself.