Resque Lock

A Resque plugin. Requires Resque 1.7.0.

This plugin is a modification of defunkt's resque-lock plugin located at https://github.com/defunkt/resque-lock

All credit goes to defunkt.

If you want only one instance of your job running at a time, but to also re-enqueue rejected jobs, extend it with this module.

For example:

require 'resque/plugins/retry_on_lock'

class UpdateNetworkGraph
  extend Resque::Plugins::RetryOnLock

  def self.perform(repo_id)
    heavy_lifting
  end
end

While other UpdateNetworkGraph jobs will be placed on the queue, the Locked class will check Redis to see if any others are executing with the same arguments before beginning. If another is executing the job will be re-enqueued.

If you want to define the key yourself you can override the lock class method in your subclass, e.g.

class UpdateNetworkGraph
  extend Resque::Plugins::RetryOnLock

  Run only one at a time, regardless of repo_id.
  def self.lock(repo_id)
    "network-graph"
  end

  def self.perform(repo_id)
    heavy_lifting
  end
end

The above modification will ensure only one job of class UpdateNetworkGraph is running at a time, regardless of the repo_id. Normally a job is locked using a combination of its class name and arguments.

resque-retry-on-lock

Resque Lock