launchpad development
Celery Jobs
Celery Jobs are not yet ready for production, because fast-lane/slow-lane work is not complete.
However, all active job types have been migrated to support running under Celery.
Data flow
The database remains the authoritative source of information about a job. Celery is merely a mechanism for running that job. Each attempt to run a job will use its own Celery task.
This may change in the future, because there are many similarities between Celery's Task class and Launchpad's Job class. They could merge, or one could replace the other.
Additional Requirements
Job factory methods should call Job.celeryRunOnCommit(). This schedules the job to run if/when the current transaction is committed. It only affects jobs whose class names are in the jobs.celery.enabled_classes feature flag.
Jobs must provide a 'config' member, which is meant to be a config section, e.g. lp.services.config.config.branchscanner. This member must have a dbuser attribute. The dbuser for each job type should be unique, to aid debugging production problems.
Database job classes such as BranchJob must provide a 'makeDerived' member which returns an IRunnableJob implementation. If there are no derived classes, as with POFileStatsJob, it should simply return itself.
Job classes should provide a 'context' member which is a database class.
