Richard Clamp

NAME

OpenFrame - a framework for network enabled applications

SYNOPSIS

  use OpenFrame;

DESCRIPTION

OpenFrame is a framework for network services serving to multiple media channels - for instance, the web, WAP, and digital television. It is built around the Pipeline API, and provides extra abstraction to make delivery of a single application to multiple channels easier.

GLOBAL VARIABLES

The most important thing that this module does is provide a wrapper around OpenFrame specific debug information - for example, the information provided by OpenFrame segments.

This variable is a hash called %DEBUG in the OpenFrame package. If you set the ALL key to a true value, then debugging information about all segments will be printed. If you want to resolve your debugging output to a single module, then set a key that matches the segments name to a true value. For example, setting $OpenFrame::DEBUG{'OpenFrame::Segment::HTTP::Request'} to 1 would mean that all the debug messages from the HTTP::Request segment would get printed.

SETTING UP YOUR SERVER

This will briefly explain how to set up a stand-alone OpenFrame server. It uses the code listing below.

The first few lines (01-08) simply load all the modules that are needed to setup the various constituent parts of an OpenFrame server. Lines 9 creates an HTTP daemon listening on port 8080 for requests, in the case that the server cannot be created line 10 provides error reporting to the screen.

The first real piece of OpenFrame code is found at line 14, where we create a Pipeline object, followed quickly by lines 16, 17 and 18 which create a couple of pipeline segments that will be added to the pipeline at line 21. Lines 24 and 26 create a loop to listen for and accept connections, and fetch HTTP requests from those connections as and when it is needed.

At line 28 we create a Pipeline::Store::Simple object, which will act as our data container for the information flowing down the pipeline. We add the request to the store and the store to the pipeline at line 31, and then call the dispatch() method on the pipeline at line 34. This sets the OpenFrame side of things going. At line 37 we ask the pipeline for the store and the store for an HTTP::Response object, and then send it back to the client at line 40.

The real work of OpenFrame is in the segments that are created, and the order in which they are inserted into the Pipeline. With this in mind, you know everything there is to know about OpenFrame.

CODE LISTING

  01: use strict;
  02: use warnings;
  03:
  04: use Pipeline;
  05: use HTTP::Daemon;
  06: use OpenFrame::Segment::HTTP::Request;
  07: use OpenFrame::Segment::ContentLoader;
  08:
  09: my $d = HTTP::Daemon->new( LocalPort => '8080', Reuse => 1);
  10: die $! unless $d;
  11:
  12: print "server running at http://localhost:8080/\n";
  13:
  14: my $pipeline = Pipeline->new();
  15:
  16: my $hr = OpenFrame::Segment::HTTP::Request->new();
  17: my $cl = OpenFrame::Segment::ContentLoader->new()
  18:                                        ->directory("./webpages");
  19:
  20:
  21: $pipeline->add_segment( $hr, $cl );
  22:
  23:
  24: while(my $c = $d->accept()) {
  25:
  26:   while(my $r = $c->get_request) {
  27:
  28:     my $store = Pipeline::Store::Simple->new();
  29:
  30:
  31:     $pipeline->store( $store->set( $r ) );
  32:
  33:
  34:     $pipeline->dispatch();
  35:
  36:
  37:     my $response = $pipeline->store->get('HTTP::Response');
  38:
  39:
  40:     $c->send_response( $response );
  41:   }
  42: }

SEE ALSO

perl(1) Pipeline(3) OpenFrame::Config(3)

AUTHOR

James A. Duncan <jduncan@fotango.com>