ResultTimeout when using SqliteQueueDatabase in forked process

I tried your new SqliteQueueDatabase which appears to be awesome and exactly what I needed to get rid of some ugly database is locked errors. Unfortunately I can’t get it to work inside a forked process. I use os.fork() to run my program as a daemon process. The next time I try to access to the database I get:

Traceback (most recent call last):
  File "/home/user/app/nzbhydra/libs/flask/app.py", line 1475, in full_dispatch_request
    rv = self.dispatch_request()
  File "/home/user/app/nzbhydra/libs/flask/app.py", line 1461, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/home/user/app/nzbhydra/nzbhydra/web.py", line 338, in wrapped_function
    return f(*args, **kwargs)
  File "/home/user/app/nzbhydra/libs/webargs/core.py", line 368, in wrapper
    return func(*new_args, **kwargs)
  File "/home/user/app/nzbhydra/nzbhydra/web.py", line 667, in internalapi_search
    searchResult = startSearch(search_request)
  File "/home/user/app/nzbhydra/nzbhydra/web.py", line 631, in startSearch
    results = search.search(search_request)
  File "/home/user/app/nzbhydra/nzbhydra/search.py", line 225, in search
    oldSearchResultsCount = SearchResult.select().where(SearchResult.firstFound < (datetime.date.today() - datetime.timedelta(days=keepFor))).count()
  File "/home/user/app/nzbhydra/libs/peewee.py", line 3086, in count
    return self.aggregate(convert=False) or 0
  File "/home/user/app/nzbhydra/libs/peewee.py", line 3079, in aggregate
    return self._aggregate(aggregation).scalar(convert=convert)
  File "/home/user/app/nzbhydra/libs/peewee.py", line 2850, in scalar
    row = self._execute().fetchone()
  File "/home/user/app/nzbhydra/libs/playhouse/sqliteq.py", line 92, in fetchone
    self._wait()
  File "/home/user/app/nzbhydra/libs/playhouse/sqliteq.py", line 51, in _wait
    raise ResultTimeout('results not ready, timed out.')

I realize this use case / problem is somewhat obscure but would be happy for any help. Thank you.

Edit: I’m currently trying to write a script that reproduces this but, of course, haven’t been able so far.

[coleifer]

Thanks so much! I’d be happy to send you a tip or a postcard or what not

Thanks for the offer, the best thanks you can give me is to continue creating issues. In this case there wasn’t a bug, technically, but I’m sure other people will have the same question and hopefully find our discussion.

[theotherp]

Alright, thanks again and I’ll definitely open tickets when I have questions or found a bug that’s actually one 😉