QueueDispatcher for Rails3
This Rails3 Gem implements a method to perform long running methods in the background. Background tasks will be executed by persistent workers.
Install
Inside your Gemfile:
gem "queue_dispatcher"
and then run:
bundle install
To install the queue_worker_dispatcher script, which starts all workers, execute the following rake command:
rake queue_dispatcher:sync
Database Setup
Use
rails g queue_dispatcher:migration
This will create a database migration for the models Task and TaskQueues.
Gem Dependencies
Please check if all those requirements are satisfied on your environment.
- rails >= 3.0.0
- sys-proctable >= 0.9.1
Inside your application
To enqueue a long running task, simple call a method through enque. E.g.: Assume, you have a long running job:
LongRunningMailJob.send_mail
Now we'd like to execute it in the background by simply calling:
task = LongRunningMailJob.enqueue.send_mail
If you like to put the job in a queue, you can do this by execute it the following way:
task = LongRunningMailJob.enqueue(queue: 'queue_name').send_mail
Jobs inside a queue are executed serialized, not in parallel. You can define dependencies. A task is then executed only after all dependent tasks are finished. The dependencies could also be in another queue. This way you could ensure, that a task is only executed when another task from another queue is successfully finished. Code to add Task dependencies:
task.dependent_tasks = another_task
Queue Worker Dispatcher
The QueueWorkerDispatcher-script starts the workers (default are 10 workers). A worker waits for a new queue and executes all tasks of this queue. Start the QueueWorkerDispatcher by executing the following command:
script/queue_worker_dispatcher
To start the QueueWorkerDispatcher as a daemon, use the option -b.
-b, --background work in background mode
Copyright
Copyright (c) 2011-2012 Philip Kurmann. See LICENSE for details.