def buffer(self):
if not hasattr(self, "_buffer"):
self._buffer = memcache.get(self._memcache_station_buffer_id)
if self._buffer is None:
station = self.station
if station is not None and station.broadcasts is not None:
keys = station.broadcasts
broadcasts_entities = db.get(keys)
broadcasts = Broadcast.get_extended_broadcasts(broadcasts_entities, self.station)
else:
broadcasts = []
timestamp = self.station.timestamp
self._buffer = {
'broadcasts': broadcasts,
'timestamp': timestamp
}
memcache.add(self._memcache_station_buffer_id, self._buffer)
logging.info("Buffer put in memcache")
else:
logging.info("Buffer retrieved from memcache")
return self._buffer
def put_buffer(self, buffer):
station = self.station
new_timestamp = buffer['timestamp']
new_broadcasts = buffer['broadcasts']
#Retrieving broadcasts from datastore
key_names = []
for i in xrange(0,len(new_broadcasts)):
b = new_broadcasts[i]
key_names.append(b['key_name'])
broadcasts = Broadcast.get_by_key_name(key_names)
b_keys = []
for i in xrange(0,len(broadcasts)):
b_key = broadcasts[i]
b_keys.append(b_key.key())
station.timestamp = new_timestamp
station.broadcasts = b_keys
station.active = datetime.utcnow()
station.put()
logging.info("Buffer put in datastore")
self._buffer = {
'broadcasts':new_broadcasts,
'timestamp': new_timestamp
}
memcache.set(self._memcache_station_id, station)
logging.info("Station updated in memcache")
memcache.set(self._memcache_station_buffer_id, self._buffer)
logging.info("Buffer updated in memcache")
def get(self, key_name):
broadcast = Broadcast.get_by_key_name(key_name)
if(broadcast):
m = re.match(r"(\w+).(\w+)", key_name)
shortname = m.group(1)
self.station_proxy = StationApi(shortname)
user_agent = self.request.headers["User-Agent"]
facebook_agent = "facebookexternalhit/1.1 (+http://www.facebook.com/externalhit_uatext.php)"
if(user_agent != facebook_agent):
# Redirect to station
self.redirect("/" + shortname)
else:
# Facebook linter
station = self.station_proxy.station
template_values = {
"broadcast" : broadcast,
}
self.render("station/facebook/broadcast.html", template_values)
else:
# 404 error
self.render("station/404.html", None)
def add_track_to_buffer(self,incoming_track):
buffer = self.reorder_buffer(self.buffer)
new_broadcasts = buffer['broadcasts'][::] # Copy array and resting broadcasts
timestamp = buffer['timestamp']
room = self.room_in_buffer()
# Edge Case, if adding track to position 1 5 seconds before the live track ends, we reject the operation.
# This is due to the latency of Pubnub.
if(len(new_broadcasts) == 1):
# We need to check if the live track ends in the next 5 seconds
live_broadcast = new_broadcasts[0]
live_broadcast_duration = live_broadcast['duration']
start = timegm(datetime.utcnow().utctimetuple()) - timegm(timestamp.utctimetuple())
time_before_end = live_broadcast_duration-start
if(time_before_end< 5):
# Rejecting action
logging.info("Rejecting operation because of an edge case (adding)")
return None
# End of edge case
extended_broadcast = None
if(room > 0):
logging.info("Room in buffer")
track = Track.get_or_insert(incoming_track, self.station)
if track:
logging.info("Track found")
submitter_key = None
if(incoming_track["track_submitter_key_name"] != self.station.key().name()):
submitter_key_name = incoming_track["track_submitter_key_name"]
submitter_key = db.Key.from_path("Station", submitter_key_name)
if(track.youtube_id):
new_broadcast = Broadcast(
key_name = incoming_track["key_name"],
track = track.key(),
youtube_id = track.youtube_id,
youtube_title = track.youtube_title,
youtube_duration = track.youtube_duration,
station = self.station.key(),
submitter = submitter_key,
)
else:
new_broadcast = Broadcast(
key_name = incoming_track["key_name"],
track = track.key(),
soundcloud_id = track.soundcloud_id,
soundcloud_title = track.soundcloud_title,
soundcloud_duration = track.soundcloud_duration,
soundcloud_thumbnail = track.soundcloud_thumbnail,
station = self.station.key(),
submitter = submitter_key,
)
new_broadcast.put()
logging.info("New broadcast put in datastore")
extended_broadcast = Broadcast.get_extended_broadcasts([new_broadcast], self.station)[0]
# Injecting traks in buffer
new_broadcasts.append(extended_broadcast)
new_buffer = {
'broadcasts': new_broadcasts,
'timestamp': timestamp
}
# Save data
self.put_buffer(new_buffer)
else:
logging.info("Track not found")
else:
logging.info("There is no more room in the buffer.")
return extended_broadcast
def delete(self):
cursor = self.request.get("cursor")
track_id = self.request.get("track_id")
typeModel = self.request.get("type")
if(track_id):
track = Track.get_by_id(int(track_id))
logging.info("Getting from datastore track with track_id = " + track_id)
if(track):
logging.info("Track found")
if(typeModel == "broadcast"):
# Deleting broadcasts associated to track
query = Broadcast.all()
query.filter("track", track)
if(cursor):
logging.info("Cursor found")
query.with_cursor(start_cursor = cursor)
broadcasts = query.fetch(100)
logging.info("Fetched : %d Broadcast(s) from datastore."%(len(broadcasts)))
if(len(broadcasts)>0):
db.delete(broadcasts)
logging.info("Deleted : %d Broadcast(s) from datastore."%(len(broadcasts)))
task = Task(
method = 'DELETE',
url = "/taskqueue/deletetrack",
params = {
"cursor": cursor,
"track_id": track_id,
"type": typeModel,
}
)
task.add(queue_name="worker-queue")
else:
task = Task(
method = 'DELETE',
url = "/taskqueue/deletetrack",
params = {
"track_id": track_id,
"type": "like",
}
)
task.add(queue_name="worker-queue")
elif (typeModel == "like"):
# Deleting likes associated to track
query = Like.all()
query.filter("track", track)
if(cursor):
logging.info("Cursor found")
query.with_cursor(start_cursor = cursor)
like = query.get()
if like is None:
logging.info("No like for this track, deleting track.")
track.delete()
else:
try:
listener_proxy = StationApi(like.listener.shortname)
listener_proxy.decrement_likes_counter()
logging.info("Listener Like counter decremented")
except:
logging.info("User has not created a station (likes used to be linked to user to stations)")
Track.decrement_likes_counter(track.key().id())
logging.info("Track likes counter decremented")
like.delete()
logging.info("Like deleted from datastore")
cursor = query.cursor()
task = Task(
method = 'DELETE',
url = "/taskqueue/deletetrack",
params = {
"cursor": cursor,
"track_id": track_id,
"type": typeModel,
}
)
task.add(queue_name="worker-queue")
response = True
else:
response = False
self.response.out.write(json.dumps({ "response": response }))
