Evaluate job schedulers libraries alternatives compatible with twisted

[evilaliv3]

was "Evaluate to re-integrate APScheduler"

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This ticket is to evaluate the re-integration of APScheduler as job scheduler.

APScheduler was removed by me implementing a basic scheduler time ago when APScheduler was not officially supporting the integration with Twisted. That was causing variuos incompatibility issues that i decided to solve by implementing basic scheduling functionalities on top of the twisted reactor.

Nowadays this has become a limit because of the impossibility to monitor/stop/pause/restart a job.

All this capabilities seems to be now available int APScheduler is now mentioning official twisted support.

In addition the library seems to benefit of active development, has an important quality assurance with 93% of code coverage.

This ticket is to track the tests of the re-integration and the various alternatives evaluations.

[evilaliv3]

Sometimes they come back: https://www.youtube.com/watch?v=89esFmj7sZk

[evilaliv3]

This was the previous implementation: https://github.com/globaleaks/GlobaLeaks/commit//ea0b6d45004f0dd80cdb33018d080aaea7ccff96

[evilaliv3]

No suitable solution exists off the shelf up to October 2016.

This makes our current custom solution remain sadly the best choice :/

Putting the ticket out of any milestone.