source: server/lib/gutenbach/server/player.py @ cf0d7e8

import logging
import threading
import subprocess
import time
from . import sync

# initialize logger
logger = logging.getLogger(__name__)

class Player(threading.Thread):

    def __init__(self, fh, *args, **kwargs):
        self.lock = threading.RLock()

        with self.lock:
            super(Player, self).__init__(*args, **kwargs)
            self.fh = fh
            self.player = None
            self._callback = None
            self._paused = False
            self._done = False
            self._dryrun = False
            self._dryrun_time = 0.5
            self._lag = 0.01

    @property
    @sync
    def is_playing(self):
        if self._dryrun:
            return self.isAlive() and not self.is_done
        else:
            return self.isAlive() and \
                      not self.is_done and \
                      self.player is not None and \
                      self.player.poll() is None

    @property
    @sync
    def is_paused(self):
        return self.is_playing and self._paused

    @property
    def is_done(self):
        return self._done

    @property
    def callback(self):
        return self._callback
    @callback.setter
    @sync
    def callback(self, val):
        self._callback = val

    def start(self):
        super(Player, self).start()
        time.sleep(self._lag)

    def run(self):
        if self.fh is None:
            raise ValueError, "file handler is None"
        
        logger.info("playing file '%s'" % self.fh.name)

        with self.lock:
            self._paused = False
            self._done = False

        command = ["mplayer", "-really-quiet", "-slave", self.fh.name]
        logger.info("running '%s'", " ".join(command))

        if self._dryrun:
            step = 0.01
            while self._dryrun_time > 0:
                time.sleep(step)
                self._dryrun_time -= step
                while self.is_paused:
                    time.sleep(0.01)

        else:
            with self.lock:
                self.player = subprocess.Popen(
                    command,
                    stdin=subprocess.PIPE,
                    stderr=subprocess.PIPE,
                    stdout=subprocess.PIPE)

            # wait for mplayer to finish
            while True:
                with self.lock:
                    playing = self.is_playing
                if not playing:
                    break
                time.sleep(0.1)

            logger.info("mplayer finished with code %d" % self.player.returncode)
        
            # get output from mplayer and log it
            with self.lock:
                stderr = self.player.stderr.read()
                stdout = self.player.stdout.read()
            
            if stderr.strip() != "":
                logger.error(stderr)
            if stdout.strip() != "":
                logger.debug(stdout)

        with self.lock:
            if self.callback:
                self.callback()
            self._done = True

    def mplayer_pause(self):
        # Note: Inner lock due to sleep.
        with self.lock:
            if self.is_playing:
                if not self._dryrun:
                    self.player.stdin.write("pause\n")
                self._paused = not(self._paused)
                logger.info("paused: %s", self.is_paused)
            else:
                logger.warning("trying to pause non-playing job")
        time.sleep(self._lag)
                
    def mplayer_stop(self):
        # Note: Inner Lock due to join.
        with self.lock:
            if self.is_playing:
                if not self._dryrun:
                    self.player.stdin.write("quit\n")
                else:
                    self._dryrun_time = 0.0
                logger.info("stopped")
            else:
                logger.warning("trying to stop non-playing job")
        self.join()