Provided by: libperlbal-perl_1.80-3_all bug


       Perlbal::Plugin::Cgilike - Handle Perlbal requests with a Perl subroutine


       This module allows responses to be handled with a simple API that's similar in principle
       to CGI, mod_perl response handlers, etc.

       It does not, however, come anywhere close to conforming to the CGI "standard". It's
       actually more like mod_perl in usage, though there are several differences.  Most notably,
       Perlbal is single-process and single-threaded, and handlers run inside the Perlbal process
       and must therefore return quickly and not do any blocking operations.

       As it currently stands, this is very bare-bones and has only really been used with basic
       GET requests. It lacks a nice API for handling the body of a POST or PUT request.

       It is not recommended to use this for extensive applications. Perlbal is first and
       foremost a load balancer, so if you're doing something at all complicated you're probably
       better off using something like Apache mod_perl and then putting Perlbal in front if it if
       necessary.  However, this plugin may prove useful for simple handlers or perhaps embedding
       a simple HTTP service into another application that uses "Danga::Socket".


       This module provides a Perlbal plugin which can be loaded and used as follows.

               LOAD cgilike
               PERLREQUIRE = MyPackage

               CREATE SERVICE cgilike
                       SET role   = web_server
                       SET listen =
                       SET plugins = cgilike
                       PERLHANDLER = MyPackage::handler
               ENABLE cgilike

       With this plugin loaded into a particular service, the plugin will then be called for all
       requests for that service.

       Set cgilike.handler to the name of a subroutine that will handle requests. This subroutine
       will receive an object which allows interaction with the Perlbal service.

               package MyPackage
               sub handler {
                   my ($r) = @_;
                       if ($r->uri eq '/') {
                               print "<p>Hello, world</p>";
                               return Perlbal::Plugin::Cgilike::HANDLED;
                       else {
                               return 404;

       Return "Perlbal::Plugin::Cgilike::HANDLED" to indicate that the request has been handled,
       or return some HTTP error code to produce a predefined error message.  You may also return
       "Perlbal::Plugin::Cgilike::DECLINED" if you do not wish to handle the request, in which
       case Perlbal will be allowed to handle the request in whatever way it would have done
       without Cgilike loaded.

       If your handler returns any non-success value, it MUST NOT produce any output. If you
       produce output before returning such a value, the response to the client is likely to be
       utter nonsense.

       You may also return "Perlbal::Plugin::Cgilike::POSTPONE_RESPONSE", which is equivalent to
       returning zero except that the HTTP connection will be left open once you return. It is
       your responsibility to later call "$r->end_response()" when you have completed the
       response. This style is necessary when you need to perform some long operation before you
       can return a response; you'll need to use some appropriate method to set a callback to run
       when the operation completes and then do your response in the callback. Once you've called
       "end_response", you must not call any further methods on $r; it's probably safest to just
       return immediately afterwards to avoid any mishaps.


       TODO: Write this


       Currently there is no API for dealing with the body of a POST or PUT request. Ideally it'd
       be able to do automatic decoding of application/x-www-form-urlencoded data, too.

       The POSTPONE_RESPONSE functionality has not been tested extensively and is probably buggy.


       Copyright 2007 Martin Atkins <> and Six Apart Ltd.

       This module is part of the Perlbal distribution, and as such can be distributed under the
       same licence terms as the rest of Perlbal.