NAME

       Plack - Perl Superglue for Web frameworks and Web Servers (PSGI toolkit)

DESCRIPTION

       Plack is a set of tools for using the PSGI stack. It contains middleware components, a
       reference server and utilities for Web application frameworks. Plack is like Ruby's Rack
       or Python's Paste for WSGI.

       See PSGI for the PSGI specification and PSGI::FAQ to know what PSGI and Plack are and why
       we need them.

MODULES AND UTILITIES

   Plack::Handler
       Plack::Handler and its subclasses contains adapters for web servers. We have adapters for
       the built-in standalone web server HTTP::Server::PSGI, CGI, FCGI, Apache1, Apache2 and
       HTTP::Server::Simple included in the core Plack distribution.

       There are also many HTTP server implementations on CPAN that have Plack handlers.

       See Plack::Handler when writing your own adapters.

   Plack::Loader
       Plack::Loader is a loader to load one Plack::Handler adapter and run a PSGI application
       code reference with it.

   Plack::Util
       Plack::Util contains a lot of utility functions for server implementors as well as
       middleware authors.

   .psgi files
       A PSGI application is a code reference but it's not easy to pass code reference via the
       command line or configuration files, so Plack uses a convention that you need a file named
       "app.psgi" or similar, which would be loaded (via perl's core function "do") to return the
       PSGI application code reference.

         # Hello.psgi
         my $app = sub {
             my $env = shift;
             # ...
             return [ $status, $headers, $body ];
         };

       If you use a web framework, chances are that they provide a helper utility to
       automatically generate these ".psgi" files for you, such as:

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

       It's important that the return value of ".psgi" file is the code reference. See
       "eg/dot-psgi" directory for more examples of ".psgi" files.

   plackup, Plack::Runner
       plackup is a command line launcher to run PSGI applications from command line using
       Plack::Loader to load PSGI backends. It can be used to run standalone servers and FastCGI
       daemon processes. Other server backends like Apache2 needs a separate configuration but
       ".psgi" application file can still be the same.

       If you want to write your own frontend that replaces, or adds functionalities to plackup,
       take a look at the Plack::Runner module.

   Plack::Middleware
       PSGI middleware is a PSGI application that wraps an existing PSGI application and plays
       both side of application and servers. From the servers the wrapped code reference still
       looks like and behaves exactly the same as PSGI applications.

       Plack::Middleware gives you an easy way to wrap PSGI applications with a clean API, and
       compatibility with Plack::Builder DSL.

   Plack::Builder
       Plack::Builder gives you a DSL that you can enable Middleware in ".psgi" files to wrap
       existent PSGI applications.

   Plack::Request, Plack::Response
       Plack::Request gives you a nice wrapper API around PSGI $env hash to get headers, cookies
       and query parameters much like Apache::Request in mod_perl.

       Plack::Response does the same to construct the response array reference.

   Plack::Test
       Plack::Test is a unified interface to test your PSGI application using standard
       HTTP::Request and HTTP::Response pair with simple callbacks.

   Plack::Test::Suite
       Plack::Test::Suite is a test suite to test a new PSGI server backend.

CONTRIBUTING

   Patches and Bug Fixes
       Small patches and bug fixes can be either submitted via nopaste on IRC
       <irc://irc.perl.org/#plack> or the github issue tracker
       <http://github.com/plack/Plack/issues>.  Forking on github <http://github.com/plack/Plack>
       is another good way if you intend to make larger fixes.

       See also <http://contributing.appspot.com/plack> when you think this document is terribly
       outdated.

   Module Namespaces
       Modules added to the Plack:: sub-namespaces should be reasonably generic components which
       are useful as building blocks and not just simply using Plack.

       Middleware authors are free to use the Plack::Middleware:: namespace for their middleware
       components. Middleware must be written in the pipeline style such that they can chained
       together with other middleware components.  The Plack::Middleware:: modules in the core
       distribution are good examples of such modules. It is recommended that you inherit from
       Plack::Middleware for these types of modules.

       Not all middleware components are wrappers, but instead are more like endpoints in a
       middleware chain. These types of components should use the Plack::App:: namespace. Again,
       look in the core modules to see excellent examples of these (Plack::App::File,
       Plack::App::Directory, etc.).  It is recommended that you inherit from Plack::Component
       for these types of modules.

       DO NOT USE Plack:: namespace to build a new web application or a framework. It's like
       naming your application under CGI:: namespace if it's supposed to run on CGI and that is a
       really bad choice and would confuse people badly.

AUTHOR

       Tatsuhiko Miyagawa

COPYRIGHT

       The following copyright notice applies to all the files provided in this distribution,
       including binary files, unless explicitly noted otherwise.

       Copyright 2009-2013 Tatsuhiko Miyagawa

CORE DEVELOPERS

       Tatsuhiko Miyagawa (miyagawa)

       Tokuhiro Matsuno (tokuhirom)

       Jesse Luehrs (doy)

       Tomas Doran (bobtfish)

       Graham Knop (haarg)

CONTRIBUTORS

       Yuval Kogman (nothingmuch)

       Kazuhiro Osawa (Yappo)

       Kazuho Oku

       Florian Ragwitz (rafl)

       Chia-liang Kao (clkao)

       Masahiro Honma (hiratara)

       Daisuke Murase (typester)

       John Beppu

       Matt S Trout (mst)

       Shawn M Moore (Sartak)

       Stevan Little

       Hans Dieter Pearcey (confound)

       mala

       Mark Stosberg

       Aaron Trevena

SEE ALSO

       The PSGI specification upon which Plack is based.

       <http://plackperl.org/>

       The Plack wiki: <https://github.com/plack/Plack/wiki>

       The Plack FAQ: <https://github.com/plack/Plack/wiki/Faq>

LICENSE

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