Perlbal::Plugin::CgiliUser)Contributed Perl DocumenPerlbal::Plugin::Cgilike(3)NAMEPerlbal::Plugin::Cgilike - Handle Perlbal requests with a Perl
subroutine
DESCRIPTION
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".
SYNOPSIS
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 = 127.0.0.1:80
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.
API DOCUMENTATION
TODO: Write this
TODO
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 AND LICENSE
Copyright 2007 Martin Atkins <mart@degeneration.co.uk> 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.
perl v5.14.2 2010-12-20 Perlbal::Plugin::Cgilike(3)
