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+---
+date: 2010-04-14T00:00:00Z
+summary: In which I introduce presque
+title: presque, a Redis / Tatsumaki based message queue
+---
+
+[presque](http://github.com/franckcuny/presque/tree/) is a small message queue service build on top of [redis](http://code.google.com/p/redis/) and [Tatsumaki](http://search.cpan.org/perldoc?Tatsumaki). It's heavily inspired by [RestMQ](http://github.com/gleicon/restmq) and [resque](http://github.com/defunkt/resque).
+
+* Communications are done in JSON over HTTP
+* Queues and messages are organized as REST resources
+* A worker can be writen in any language that make a HTTP request and read JSON
+* Thanks to redis, the queues are persistent
+
+## Overview
+
+resque need a configuration file, writen in YAML that contains the host and port for the Redis server.
+
+```yaml
+redis:
+    host: 127.0.0.1
+    port: 6379
+```
+
+Let's start the server:
+
+```bash
+% plackup app.psgi --port 5000
+```
+
+The applications provides some HTTP routes:
+
+* **/**: a basic HTML page with some information about the queues
+* **/q/**: REST API to get and post job to a queue
+* **/j/**: REST API to get some information about a queue
+* **/control/**: REST API to control a queue (start or stop consumers)
+* **/stats/**: REST API to fetch some stats (displayed on the index page)
+
+Queues are created on the fly, when a job for an unknown queue is inserted. When a new job is created, the JSON send in the POST will be stored "as is". There is no restriction on the schema or the content of the JSON.
+
+Creating a new job simply consist to :
+
+```bash
+% curl -X POST "http://localhost:5000/q/foo" -d '{"foo":"bar", "foo2":"bar" }'
+```
+
+and fetching the job:
+
+```bash
+% curl "http://localhost:5000/q/foo"
+```
+
+When a job is fetched, it's removed from the queue.
+
+## A basic worker
+
+I've also pushed [presque::worker](http://git.lumberjaph.net/p5-presque-worker.git/). It's based on [AnyEvent::HTTP](http://search.cpan.org/perldoc?AnyEvent::HTTP) and [Moose](http://search.cpan.org/perldoc?Moose). Let's write a basic worker using this class:
+
+```perl
+use strict;
+use warnings;
+use 5.012;    # w00t
+
+package simple::worker;
+use Moose;
+extends 'presque::worker';
+
+sub work {
+    my ($self, $job) = @_;
+    say "job's done";
+    ...;      # yadda yadda!
+    return;
+}
+
+package main;
+use AnyEvent;
+
+my $worker =
+    simple::worker->new(base_uri => 'http://localhost:5000', queue => 'foo');
+
+AnyEvent->condvar->recv;
+```
+
+A worker have to extends the presque::worker class, and implement the method *work*. When the object is created, the class check if this method is avalaible. You can also provide a `fail` method, which will be called when an error occur.
+
+## The future
+
+I plan to add support for [websocket](http://en.wikipedia.org/wiki/WebSocket), and probably [XMPP](http://en.wikipedia.org/wiki/Xmpp). More functionalities to the worker too: logging, forking, handling many queues, ... I would like to add priorities to queue also, and maybe scheluding job for a given date (not sure if it's feasable with Redis).