ActiveJob::Lockable

Gem to make to make jobs lockable. Useful when a job is called N times, but only a single execution is needed.

Installation

Add this line to your application's Gemfile:

gem 'activejob-lockable'

And then execute:

$ bundle

Or install it yourself as:

$ gem install activejob-lockable

Configuration

Create an initializer with redis connection:

ActiveJob::Lockable.redis = Redis.current # if you have a redis instance

# or
ActiveJob::Lockable.redis = 'redis://localhost:6379/0'
# or
ActiveJob::Lockable.redis = {
  host: '10.0.1.1',
  port: 6380,
  db: 15
}

Usage

# job
# nothing to change!

# code
MyJob.set(lock: 10.seconds).perform_later(id)

Now, after the first enqueue (perform_later), a lock will be created and the following enqueues within 10 seconds will be rejected.

Lock key

A lock key by default:

job_name_in_downcase:md5(arguments)

To override the key you can override method lock_key:

# job
def lock_key
  'my-custom-key'
end

Lock period

You can set a fixed lock_period, in that case .set(lock: N) will be ignored and the job will always be lockable:

# job
def lock_period
  1.day
end

On lock action

When a job is locked and another one is enqueued, you can set up a custom callback that will be called. This is useful if you want to raise exception or be notified:

# job
class MyJob < ApplicationJob
  on_locked :raise_if_locked

  def raise_if_locked
    raise 'Job is locked'
  end
end

Dependencies

• ActiveSupport
• ActibeJob
• Redis

Contributing

Bug reports and pull requests are welcome on GitHub at qonto/activejob-lockable. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

License

The gem is available as open source under the terms of the MIT License.

Releasing

To publish a new version to rubygems, update the version in lib/activejob/lockable/version.rb, and merge.