Rework of status handling in mythjobqueue

[Raymond Wagner]

The goal of this task is to remove (most of) the custom handling of mythcommflag and mythtranscode within the jobqueue code. The jobqueue will only be responsible for startup and success/failure logs and status updates. The jobs themselves will be responsible for any task specific information displayed in the terminal logs, database logs, or jobqueue table.

[Raymond Wagner]

Initial patch to only update comment on a status change.

[Raymond Wagner]

(In [23360]) Alter the jobqueue to only change the comment on a job if the status is being changed. This allows userjobs to provide custom exit codes in the comments without them being immediately overwritten by the jobqueue code. Refs #7990.

[stuartm]

Milestone 0.25 deleted

[Jim Stichnoth <jstichnoth@…>]

In b43b11ca3062086d20ee0072368e9dd3646a5faa/mythtv:

Reduce "Watch Recordings" sluggishness by caching jobqueue state.

Refs #8962, refs #7990.

Currently, when navigating the Watch Recordings screen, every time the
cursor position is moved, 4 jobqueue queries are issued for each item
visible on the screen (the actual number being controlled by the
theme). These queries are done within the UI thread, which makes
navigation noticeably sluggish on most any setup that isn't a
moderately powerful combined frontend/backend.

Ideally, any time a job's status changes (including queue addition and
removal), we would call ProgramInfo::SendUpdateEvent?() to get the
Watch Recordings entry updated, along with any other
ProgramInfoUpdater? subscribers. Also,
ProgramInfo::LoadProgramFromRecorded?() and LoadFromRecorded?() would
set up the necessary commflag and transcode flags in the ProgramInfo?
object.

However, in the current jobqueue implementation, this is not very
practical because of functions like:

JobQueue::DeleteJob?(int jobID)
JobQueue::ChangeJobCmds?(int jobID, int newCmds)
JobQueue::ChangeJobFlags?(int jobID, int newFlags)
JobQueue::ChangeJobStatus?(int jobID, int newStatus, QString comment)
JobQueue::ChangeJobComment?(int jobID, QString comment)
JobQueue::ChangeJobArgs?(int jobID, QString args)
JobQueue::ChangeJobHost?(int jobID, QString newHostname)
JobQueue::CleanupOldJobsInQueue?()

where the ProgramInfo? isn't readily available (though it could be
found given another query on jobID for all but the last function).

Instead, in this approach, the PlaybackBox? locally caches the jobqueue
contents, reloading every 15 seconds as needed. The reload blocks the
UI thread, but only for a small fraction of the time that the current
implementation was blocking it, so it's unlikely a user pay much
attention to this once-in-15-seconds query.

This code should be removed once #7990 makes jobs more autonomous.

[Jim Stichnoth <jstichnoth@…>]

In 974d1ae9b6fe2f12b8cfc48aafcf10fc730e414e/mythtv:

Reduce "Watch Recordings" sluggishness by caching jobqueue state.

Refs #8962, refs #7990.

This is essentially a cherry-pick of b43b11ca.

[Stuart Auchterlonie]

Milestone renamed

[Stuart Auchterlonie]

Moving remaining open tickets to 0.28.2 milestone

[Stuart Auchterlonie]

Moving remaining open tickets to 29.2 milestone