openwebrx-clone/owrx/audio.py
2021-01-22 17:34:35 +01:00

302 lines
9.2 KiB
Python

from abc import ABC, ABCMeta, abstractmethod
from owrx.config import Config
from owrx.metrics import Metrics, CounterMetric, DirectMetric
import threading
import wave
import subprocess
import os
from multiprocessing.connection import Pipe, wait
from datetime import datetime, timedelta
from queue import Queue, Full, Empty
import logging
logger = logging.getLogger(__name__)
logger.setLevel(logging.INFO)
class QueueJob(object):
def __init__(self, decoder, file, freq):
self.decoder = decoder
self.file = file
self.freq = freq
def run(self):
self.decoder.decode(self)
def unlink(self):
try:
os.unlink(self.file)
except FileNotFoundError:
pass
PoisonPill = object()
class QueueWorker(threading.Thread):
def __init__(self, queue):
self.queue = queue
self.doRun = True
super().__init__()
def run(self) -> None:
while self.doRun:
job = self.queue.get()
if job is PoisonPill:
self.doRun = False
else:
try:
job.run()
except Exception:
logger.exception("failed to decode job")
self.queue.onError()
finally:
job.unlink()
self.queue.task_done()
class DecoderQueue(Queue):
sharedInstance = None
creationLock = threading.Lock()
@staticmethod
def getSharedInstance():
with DecoderQueue.creationLock:
if DecoderQueue.sharedInstance is None:
pm = Config.get()
DecoderQueue.sharedInstance = DecoderQueue(
maxsize=pm["decoding_queue_length"], workers=pm["decoding_queue_workers"]
)
return DecoderQueue.sharedInstance
@staticmethod
def stopAll():
with DecoderQueue.creationLock:
if DecoderQueue.sharedInstance is not None:
DecoderQueue.sharedInstance.stop()
DecoderQueue.sharedInstance = None
def __init__(self, maxsize, workers):
super().__init__(maxsize)
metrics = Metrics.getSharedInstance()
metrics.addMetric("decoding.queue.length", DirectMetric(self.qsize))
self.inCounter = CounterMetric()
metrics.addMetric("decoding.queue.in", self.inCounter)
self.outCounter = CounterMetric()
metrics.addMetric("decoding.queue.out", self.outCounter)
self.overflowCounter = CounterMetric()
metrics.addMetric("decoding.queue.overflow", self.overflowCounter)
self.errorCounter = CounterMetric()
metrics.addMetric("decoding.queue.error", self.errorCounter)
self.workers = [self.newWorker() for _ in range(0, workers)]
def stop(self):
logger.debug("shutting down the queue")
try:
# purge all remaining jobs
while not self.empty():
job = self.get()
job.unlink()
self.task_done()
except Empty:
pass
# put() a PoisonPill for all active workers to shut them down
for w in self.workers:
if w.is_alive():
self.put(PoisonPill)
self.join()
def put(self, item, **kwars):
self.inCounter.inc()
try:
super(DecoderQueue, self).put(item, block=False)
except Full:
self.overflowCounter.inc()
raise
def get(self, **kwargs):
# super.get() is blocking, so it would mess up the stats to inc() first
out = super(DecoderQueue, self).get(**kwargs)
self.outCounter.inc()
return out
def newWorker(self):
worker = QueueWorker(self)
worker.start()
return worker
def onError(self):
self.errorCounter.inc()
class AudioChopperProfile(ABC):
@abstractmethod
def getInterval(self):
pass
@abstractmethod
def getFileTimestampFormat(self):
pass
@abstractmethod
def decoder_commandline(self, file):
pass
class AudioWriter(object):
def __init__(self, dsp, source, profile: AudioChopperProfile):
self.dsp = dsp
self.source = source
self.profile = profile
self.tmp_dir = Config.get()["temporary_directory"]
self.wavefile = None
self.wavefilename = None
self.switchingLock = threading.Lock()
self.timer = None
(self.outputReader, self.outputWriter) = Pipe()
def getWaveFile(self):
filename = "{tmp_dir}/openwebrx-audiochopper-{id}-{timestamp}.wav".format(
tmp_dir=self.tmp_dir,
id=id(self),
timestamp=datetime.utcnow().strftime(self.profile.getFileTimestampFormat()),
)
wavefile = wave.open(filename, "wb")
wavefile.setnchannels(1)
wavefile.setsampwidth(2)
wavefile.setframerate(12000)
return filename, wavefile
def getNextDecodingTime(self):
t = datetime.utcnow()
zeroed = t.replace(minute=0, second=0, microsecond=0)
delta = t - zeroed
interval = self.profile.getInterval()
seconds = (int(delta.total_seconds() / interval) + 1) * interval
t = zeroed + timedelta(seconds=seconds)
logger.debug("scheduling: {0}".format(t))
return t
def cancelTimer(self):
if self.timer:
self.timer.cancel()
self.timer = None
def _scheduleNextSwitch(self):
self.cancelTimer()
delta = self.getNextDecodingTime() - datetime.utcnow()
self.timer = threading.Timer(delta.total_seconds(), self.switchFiles)
self.timer.start()
def switchFiles(self):
with self.switchingLock:
file = self.wavefile
filename = self.wavefilename
(self.wavefilename, self.wavefile) = self.getWaveFile()
file.close()
job = QueueJob(self, filename, self.dsp.get_operating_freq())
try:
DecoderQueue.getSharedInstance().put(job)
except Full:
logger.warning("decoding queue overflow; dropping one file")
job.unlink()
self._scheduleNextSwitch()
def decode(self, job: QueueJob):
logger.debug("processing file %s", job.file)
decoder = subprocess.Popen(
["nice", "-n", "10"] + self.profile.decoder_commandline(job.file),
stdout=subprocess.PIPE,
cwd=self.tmp_dir,
close_fds=True,
)
try:
for line in decoder.stdout:
self.outputWriter.send((self.profile, job.freq, line))
except (OSError, AttributeError):
decoder.stdout.flush()
# TODO uncouple parsing from the output so that decodes can still go to the map and the spotters
logger.debug("output has gone away while decoding job.")
try:
rc = decoder.wait(timeout=10)
if rc != 0:
raise RuntimeError("decoder return code: {0}".format(rc))
except subprocess.TimeoutExpired:
logger.warning("subprocess (pid=%i}) did not terminate correctly; sending kill signal.", decoder.pid)
decoder.kill()
raise
def start(self):
(self.wavefilename, self.wavefile) = self.getWaveFile()
self._scheduleNextSwitch()
def write(self, data):
with self.switchingLock:
self.wavefile.writeframes(data)
def stop(self):
self.outputWriter.close()
self.outputWriter = None
# drain messages left in the queue so that the queue can be successfully closed
# this is necessary since python keeps the file descriptors open otherwise
try:
while True:
self.outputReader.recv()
except EOFError:
pass
self.outputReader.close()
self.outputReader = None
self.cancelTimer()
try:
self.wavefile.close()
except Exception:
logger.exception("error closing wave file")
try:
with self.switchingLock:
os.unlink(self.wavefilename)
except Exception:
logger.exception("error removing undecoded file")
self.wavefile = None
self.wavefilename = None
class AudioChopper(threading.Thread, metaclass=ABCMeta):
def __init__(self, dsp, source, *profiles: AudioChopperProfile):
self.source = source
self.writers = [AudioWriter(dsp, source, p) for p in profiles]
self.doRun = True
super().__init__()
def run(self) -> None:
logger.debug("Audio chopper starting up")
for w in self.writers:
w.start()
while self.doRun:
data = None
try:
data = self.source.read(256)
except ValueError:
pass
if data is None or (isinstance(data, bytes) and len(data) == 0):
self.doRun = False
else:
for w in self.writers:
w.write(data)
logger.debug("Audio chopper shutting down")
for w in self.writers:
w.stop()
def read(self):
try:
readers = wait([w.outputReader for w in self.writers])
return [r.recv() for r in readers]
except (EOFError, OSError):
return None