* return start video
* use ubuntu instead of alpine because ffmpeg in alpine lacks drawtext support
* only cache if inputs are exactly the same, preventing accidents (prev scheme too weak)
* fix a bug where end range is wrong if start_range doesn't start at 0
conceptually, this was a more serious bug as time_offset was wrong, but luckily the bug applied
equally to both racers so there was no net effect
By always using unique filepaths (except for the final result, which is written atomically)
we turn multiple simultanious calls into at worst wasted effort, instead of garbled results.
By carefully ensuring most of our dockerfiles are identical in their first few layers,
we only need to build those layers once instead of every time.
In particular, we move installing gevent to before installing common,
so that even when common changes gevent doesn't need to be reinstalled.
This is important because gevent takes ages to install.
Also fixes segment_coverage, which wasn't being installed.
In a fast cut, we edit the first and last segments then concatenate them all.
However, this leads to some tiny but perciptible artifacting around the border
of the first and second (and second-last and last) segments.
A full cut is much slower, but re-encodes the video into the desired format
and is more reliable.
We want both options to be available.
With this commit, we only add the option, we don't use it in restreamer or cutter.
We wrap direct dateutil calls to handle two distinct cases:
* `common.dateutil.parse()`: We want to handle arbitrary timestamps including tz info,
then convert them to UTC.
This is used in HLS parsing, and for command line input for backfiller
* `common.dateutil.parse_utc_only()`: We want to only handle UTC timestamps,
but datetime.strptime isn't flexible enough (eg. can't handle missing fractional component).
This is used for restreamer request params.
Note this moves over the 'experimental' cutter and deletes the original cutter
that concatenates entire videos before cutting.
We may eventually want to revive that method if the experimental cutter turns out
to introduce too many issues.
We move most of the code over verbatim, but adjust it such that it acts
as a generic iterator that can be used in a variety of contexts.
Some other changes made during the move include telling ffmpeg to be quieter
(don't output version info and junk, only log if something goes wrong),
and avoiding errors during cleanup.
Backdoor allows the operator to telnet into the given port, and get a python shell
running inside the process, from which you can debug, modify state (eg. set the log level),
or whatever. This is extremely useful for debugging weird states that you encounter randomly
but can't easily reproduce, without restarting the process and needing to wait until it happens again.
Prom client doesn't like you creating two stats with the same name,
even though they have different labels and this makes perfect sense.
I feel like I just need to re-write the prom client at some point - it doesn't actually
do all that much except get in your way, apart from the actual text encoding which I
can steal.
Anyway, in the meantime, we get around this by breaking up metrics into two names,
a "foo_all" and a "foo_ENDPOINT". The foo_all lacks the detailed labels,
but is still labelled by endpoint and can be used more easily.
The foo_ENDPOINT labels have more information but require messier PromQL as you need to
match on a name regex if you want to look at more than one specific endpoint.
I had to go to some effort to get nice labelling,
which also meant none of the existing libs for this were any good,
but this works well enough.
Exposes the metrics on /metrics.