Catalyst::Engine::PSGI(3) PSGI engine for Catalyst


# app.psgi
use strict;
use MyApp;
my $app = sub { MyApp->run(@_) };


Catalyst::Engine::PSGI is a Catalyst Engine that adapts Catalyst into the PSGI gateway protocol.


  • Currently this engine works with Catalyst 5.8 (Catamoose) or newer.
  • Your application is supposed to work with any PSGI servers without any code modifications, but if your application uses "$c->res->write" to do streaming write, this engine will buffer the output until your app finishes.

    To do real streaming with this engine, you should implement an IO::Handle-like object that responds to "getline" method that returns chunk or undef when done, and set that object to "$c->res->body".

    Alternatively, it is possible to set the body to a code reference, which will be used to stream content as documented in the PSGI spec.

  • When your application runs behind the frontend proxy like nginx or lighttpd, this Catalyst engine doesn't automatically recognize the incoming headers like "X-Forwarded-For", because respecting these headers by default causes a potential security issue.

    You have to enable Plack::Middleware::ReverseProxy or Plack::Middleware::ForwardedHeaders to automatically promote those forwarded headers into "REMOTE_ADDR" hence IP address of the request.

    ReverseProxy middleware is pretty simple and has no configuration while ForwardedHeaders allows you to configure which upstream host to trust, etc.


Tatsuhiko Miyagawa <[email protected]>

Most of the code is taken and modified from Catalyst::Engine::CGI.


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