aircox-radiocampus/aircox/management/commands/streamer.py
2016-10-10 15:04:15 +02:00

347 lines
11 KiB
Python

"""
Handle the audio streamer and controls it as we want it to be. It is
used to:
- generate config files and playlists;
- monitor Liquidsoap, logs and scheduled programs;
- cancels Diffusions that have an archive but could not have been played;
- run Liquidsoap
"""
import os
import time
import re
from argparse import RawTextHelpFormatter
from django.conf import settings as main_settings
from django.core.management.base import BaseCommand, CommandError
from django.utils import timezone as tz
from aircox.models import Station, Diffusion, Track, Sound, Log
class Monitor:
"""
Log and launch diffusions for the given station.
Monitor should be able to be used after a crash a go back
where it was playing, so we heavily use logs to be able to
do that.
We keep trace of played items on the generated stream:
- sounds played on this stream;
- scheduled diffusions
- tracks for sounds of streamed programs
"""
station = None
streamer = None
cancel_timeout = 60*10
"""
Time in seconds before a diffusion that have archives is cancelled
because it has not been played.
"""
sync_timeout = 60*10
"""
Time in minuts before all stream playlists are checked and updated
"""
sync_next = None
"""
Datetime of the next sync
"""
def __init__(self, station, **kwargs):
self.station = station
self.__dict__.update(kwargs)
def monitor(self):
"""
Run all monitoring functions.
"""
if not self.streamer:
self.streamer = self.station.streamer
if not self.streamer.ready():
return
self.trace()
self.sync_playlists()
self.handle()
def log(self, **kwargs):
"""
Create a log using **kwargs, and print info
"""
log = Log(station = self.station, **kwargs)
log.save()
log.print()
def trace(self):
"""
Check the current_sound of the station and update logs if
needed.
"""
self.streamer.fetch()
current_sound = self.streamer.current_sound
current_source = self.streamer.current_source
if not current_sound or not current_source:
return
log = Log.objects.get_for(model = Sound) \
.filter(station = self.station) \
.order_by('date').last()
# only streamed
if log and (log.related and not log.related.diffusion):
self.trace_sound_tracks(log)
# TODO: expiration
if log and (log.source == current_source.id and \
log.related and
log.related.path == current_sound):
return
sound = Sound.objects.filter(path = current_sound)
self.log(
type = Log.Type.play,
source = current_source.id,
date = tz.now(),
related = sound[0] if sound else None,
comment = None if sound else current_sound,
)
def trace_sound_tracks(self, log):
"""
Log tracks for the given sound (for streamed programs); Called by
self.trace
"""
logs = Log.objects.get_for(model = Track) \
.filter(pk__gt = log.pk)
logs = [ log.related_id for log in logs ]
tracks = Track.objects.get_for(object = log.related) \
.filter(in_seconds = True)
if tracks and len(tracks) == len(logs):
return
tracks = tracks.exclude(pk__in = logs).order_by('position')
now = tz.now()
for track in tracks:
pos = log.date + tz.timedelta(seconds = track.position)
if pos < now:
self.log(
type = Log.Type.play,
source = log.source,
date = pos,
related = track
)
def sync_playlists(self):
"""
Synchronize updated playlists
"""
now = tz.now()
if self.sync_next and self.sync_next < now:
return
self.sync_next = now + tz.timedelta(seconds = self.sync_timeout)
for source in self.station.sources:
if source == self.station.dealer:
continue
playlist = [ sound.path for sound in
source.program.sound_set.all() ]
source.playlist = playlist
def trace_canceled(self):
"""
Check diffusions that should have been played but did not start,
and cancel them
"""
if not self.cancel_timeout:
return
diffs = Diffusions.objects.get_at().filter(
type = Diffusion.Type.normal,
sound__type = Sound.Type.archive,
)
logs = station.get_played(models = Diffusion)
date = tz.now() - datetime.timedelta(seconds = self.cancel_timeout)
for diff in diffs:
if logs.filter(related = diff):
continue
if diff.start < now:
diff.type = Diffusion.Type.canceled
diff.save()
self.log(
type = Log.Type.other,
related = diff,
comment = 'Diffusion canceled after {} seconds' \
.format(self.cancel_timeout)
)
def __current_diff(self):
"""
Return a tuple with the currently running diffusion and the items
that still have to be played. If there is not, return None
"""
station = self.station
now = tz.make_aware(tz.datetime.now())
diff_log = station.get_played(models = Diffusion) \
.order_by('date').last()
if not diff_log or \
not diff_log.related.is_date_in_range(now):
return None, []
# sound has switched? assume it has been (forced to) stopped
sounds = station.get_played(models = Sound) \
.filter(date__gte = diff_log.date) \
.order_by('date')
if sounds.last() and sounds.last().source != diff_log.source:
return diff_log, []
# last diff is still playing: get the remaining playlist
sounds = sounds.filter(
source = diff_log.source, pk__gt = diff_log.pk
)
sounds = [
sound.related.path for sound in sounds
if sound.related.type != Sound.Type.removed
]
return (
diff_log.related,
[ path for path in diff_log.related.playlist
if path not in sounds ]
)
def __next_diff(self, diff):
"""
Return the tuple with the next diff that should be played and
the playlist
Note: diff is a log
"""
station = self.station
now = tz.now()
args = {'start__gt': diff.date } if diff else {}
diff = Diffusion.objects.get_at(now).filter(
type = Diffusion.Type.normal,
sound__type = Sound.Type.archive,
**args
).distinct().order_by('start').first()
return (diff, diff and diff.playlist or [])
def handle(self):
"""
Handle scheduled diffusion, trigger if needed, preload playlists
and so on.
"""
station = self.station
dealer = station.dealer
if not dealer:
return
now = tz.now()
# current and next diffs
diff, playlist = self.__current_diff()
dealer.active = bool(playlist)
next_diff, next_playlist = self.__next_diff(diff)
playlist += next_playlist
# playlist update
if dealer.playlist != playlist:
dealer.playlist = playlist
if next_diff:
self.log(
type = Log.Type.load,
source = dealer.id,
date = now,
related = next_diff
)
# dealer.on when next_diff start <= now
if next_diff and not dealer.active and \
next_diff.start <= now:
dealer.active = True
self.log(
type = Log.Type.play,
source = dealer.id,
date = now,
related = next_diff,
)
class Command (BaseCommand):
help= __doc__
def add_arguments (self, parser):
parser.formatter_class=RawTextHelpFormatter
group = parser.add_argument_group('actions')
group.add_argument(
'-c', '--config', action='store_true',
help='generate configuration files for the stations'
)
group.add_argument(
'-m', '--monitor', action='store_true',
help='monitor the scheduled diffusions and log what happens'
)
group.add_argument(
'-r', '--run', action='store_true',
help='run the required applications for the stations'
)
group = parser.add_argument_group('options')
group.add_argument(
'-d', '--delay', type=int,
default=1000,
help='time to sleep in MILLISECONDS between two updates when we '
'monitor'
)
group.add_argument(
'-s', '--station', type=str, action='append',
help='name of the station to monitor instead of monitoring '
'all stations'
)
group.add_argument(
'-t', '--timeout', type=int,
default=600,
help='time to wait in SECONDS before canceling a diffusion that '
'has not been ran but should have been. If 0, does not '
'check'
)
def handle (self, *args,
config = None, run = None, monitor = None,
station = [], delay = 1000, timeout = 600,
**options):
stations = Station.objects.filter(name__in = station)[:] \
if station else Station.objects.all()[:]
for station in stations:
# station.prepare()
if config and not run: # no need to write it twice
station.streamer.push()
if run:
station.streamer.process_run()
if monitor:
monitors = [
Monitor(station, cancel_timeout = timeout)
for station in stations
]
delay = delay / 1000
while True:
for monitor in monitors:
monitor.monitor()
time.sleep(delay)
if run:
for station in stations:
station.controller.process_wait()