refs https://github.com/TryGhost/Toolbox/issues/357
- Job persisted in the database need to track job's execution status such as completion, failure, execution start and end times. This changeset allows to hook into job/bree lifecycle to track job's progress.
- NOTE: only supports "offloaded" jobs at the moment. Support for "inline" jobs will be added once there's a clear usecase for it.
- The "started" status and "started_at" timestamp are assigned to a job at the moment when the worker thread is created inside of bree
- The "finished" status and "finished_at" timestamp are assigned to a job when a "done" event is passed from the job script (NOTE: using process.exit(0) will not trigger the "finished" state")
- The "failed" status is assigned when the job execution is interrupted with an error
refs https://github.com/TryGhost/Toolbox/issues/357
- This is a scaffolding for what will become a one off job scheduling mechanism. The aim is allowing to run jobs which can be only ever be run once in the lifetime of the instance - persisting through restarts.
