[mythtv-users] Lost Recordings and Database

[Scott Simpson]

On 1/10/2023 4:32 AM, Stephen Worthington wrote:
> On Tue, 10 Jan 2023 14:15:24 +1300, you wrote:
>
>> On Mon, 9 Jan 2023 11:35:39 +0000, you wrote:
>>
>>> Hi All,
>>>
>>> I wonder if someone with more knowledge of the Myth Database schema
>>> might be able to advise me here. A friends Myth (0.32) system had a disk
>>> tragedy and he has lost one of two volumes where the recordings are/were
>>> held. The database entries for those recordings remain intact.
>>>
>>> Would it be possible to construct an SQL query that would take entries
>>> after a specific date in the Recorded table and arrange for those
>>> recordings to be entered into the Recording Schedules. In effect a
>>> "Delete and Re-Record" operation.
>>>
>>> Many thanks
>>>
>>> Ken
>> That certainly sounds possible.  What you would want to do would be to
>> check all recordings and get the basename field for each file, then
>> check if the file can be found on disk.  If not, then do the delete
>> and re-record.  There are API calls to list recordings with various
>> filters, and there is an API to do delete.  I would have to check if
>> the delete API has a re-record option.  If so, it would not be a
>> particularly complicated bit of Python to do this.
> The DeleteRecording API does have options to delete metadata if the
> recording file is not present and to re-record.  The GetRecording API
> will return the recording data if the recording is present, and
> presumably will do an error if it is not, so it should be able to be
> used to determine if the recording file exists.  The GetRecordedList
> API will return a list of all recordings.
>
> So what I would do would be to get the full list of recordings, then
> for each one do GetRecording and see if the file exists.  If it does,
> delete that entry in the recordings list.  Then display the list of
> recordings that have no files for the user to check.  After checking,
> the user says whether to proceed with doing a delete-and-re-record on
> each of those recordings, using the option to force a delete if the
> recording file is missing.  All of which is fairly straightforward for
> anyone who has used the MythTV Services API before, but does represent
> a few hours of work to write.
>
> I would recommend only running the program when MythTV is not busy and
> is not going to be busy for a while, as it will do a lot of database
> updates and may make it too busy to start or stop recordings properly.
See the find_orphans.py script on the net for inspiration too. It cleans 
up dead files. The only functionality it doesn't have is re-record but 
since you have database access that should be possible too.