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PSGI toolkit and server adapters
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    Plack - PSGI toolkit and servers

    Plack is a set of PSGI reference server implementations and helper
    utilities for Web application frameworks, exactly like Ruby's Rack.

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

    Plack::Server is a namespace for PSGI server implementations. We have
    Standalone, CGI, FCGI, Apache, AnyEvent, Coro, Danga::Socket and many
    server environments that you can run PSGI applications on.

    See Plack::Server how to write your own server implementation.

    Plack::Loader is a loader to load one of Plack::Server backends and run
    PSGI application code reference with it.

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

  .psgi files
    PSGI application is a code reference but it's not easy to pass code
    reference in the command line or configuration files, so Plack uses a
    convention that you need a file named "app.psgi" or alike, which would
    be loaded (via perl's core function "do") to return the PSGI application
    code reference. See eg/dot-psgi directory for the example ".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 Plack::Runner module.

    PSGI middleware is a PSGI application that wraps existent 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 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

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

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

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

  Patches and Bug Fixes
    Small patches and bug fixes can be either submitted via nopaste on IRC
    <irc://> or email. You could also fork on github
    ( to make larger fixes.

  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

    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 confuse

    Tatsuhiko Miyagawa

    Yuval Kogman

    Tokuhiro Matsuno

    Kazuhiro Osawa

    Kazuho Oku

    PSGI <>

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

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