def __init__(self, config, database):
if type(config) is not MusicDBConfig:
raise TypeError("config argument not of type MusicDBConfig")
if type(database) is not MusicDatabase:
raise TypeError("database argument not of type MusicDatabase")
self.db = database
self.cfg = config
self.mdbstate = MDBState(self.cfg.server.statedir, self.db)
self.blacklist = BlacklistInterface(self.cfg, self.db)
self.randy = Randy(self.cfg, self.db)
global Queue
global QueueLock
with QueueLock:
if Queue == None:
logging.debug("Loading Video Queue…")
try:
self.Load()
except Exception as e:
logging.warning(
"Loading video queue failed with error: %s. \033[1;30m(Creating an empty one)",
str(e))
Queue = []
def __init__(self, config, database):
if type(config) != MusicDBConfig:
raise TypeError("config argument not of type MusicDBConfig")
if type(database) != MusicDatabase:
raise TypeError("database argument not of type MusicDatabase")
self.db = database
self.cfg = config
self.mdbstate = MDBState(self.cfg.server.statedir, self.db)
self.blacklist = BlacklistInterface(self.cfg, self.db)
# Load most important keys
self.nodisabled = self.cfg.randy.nodisabled
self.nohated = self.cfg.randy.nohated
self.minlen = self.cfg.randy.minsonglen
class VideoQueue(object):
"""
This class implements a queue to manage videos to play.
Whenever the queue changes, its data gets stored in the MusicDB State Directory
When the constructor detects that there is no queue yet (not even an empty one),
it tries to load the stored queue.
If this fails, a new empty queue gets created.
Args:
config: :class:`~lib.cfg.musicdb.MusicDBConfig` object holding the MusicDB Configuration
database: A :class:`~lib.db.musicdb.MusicDatabase` instance
Raises:
TypeError: When the arguments are not of the correct type.
"""
def __init__(self, config, database):
if type(config) is not MusicDBConfig:
raise TypeError("config argument not of type MusicDBConfig")
if type(database) is not MusicDatabase:
raise TypeError("database argument not of type MusicDatabase")
self.db = database
self.cfg = config
self.mdbstate = MDBState(self.cfg.server.statedir, self.db)
self.blacklist = BlacklistInterface(self.cfg, self.db)
self.randy = Randy(self.cfg, self.db)
global Queue
global QueueLock
with QueueLock:
if Queue == None:
logging.debug("Loading Video Queue…")
try:
self.Load()
except Exception as e:
logging.warning(
"Loading video queue failed with error: %s. \033[1;30m(Creating an empty one)",
str(e))
Queue = []
#####################################################################
# Event Management #
#####################################################################
def RegisterCallback(self, function):
"""
Register a callback function that reacts on Video Queue related events.
For more details see the module description at the top of this document.
Args:
function: A function that shall be called on an event.
Returns:
*Nothing*
"""
global Callbacks
Callbacks.append(function)
def RemoveCallback(self, function):
"""
Removes a function from the list of callback functions.
Args:
function: A function that shall be called removed.
Returns:
*Nothing*
"""
global Callbacks
# Not registered? Then do nothing.
if not function in Callbacks:
logging.warning(
"A Video Queue callback function should be removed, but did not exist in the list of callback functions!"
)
return
Callbacks.remove(function)
def TriggerEvent(self, name, arg=None):
"""
This function triggers an event.
It iterates through all registered callback functions and calls them.
The arguments to the functions are the name of the even (``name``) and addition arguments (``arg``).
That argument will be ``None`` if there is no argument.
More details about events can be found in the module description at the top of this document.
Args:
name (str): Name of the event
arg: Additional arguments to the event, or ``None``
Returns:
*Nothing*
"""
global Callbacks
for callback in Callbacks:
try:
callback(name, arg)
except Exception as e:
logging.exception(
"A Video Queue event callback function crashed!")
def Event_VideoQueueChanged(self):
"""
See :meth:`~TriggerEvent` with event name ``"VideoQueueChanged"``.
More details in the module description at the top of this document.
This method also tries to save the queue into the MusicDB State Directory.
"""
try:
self.Save()
except Exception as e:
logging.warning(
"Saving the current video queue failed with error: %s. \033[1;30m(Continuing without saving)",
str(e))
self.TriggerEvent("VideoQueueChanged")
def Event_VideoChanged(self):
"""
See :meth:`~TriggerEvent` with event name ``"VideoChanged"``
More details in the module description at the top of this document.
"""
self.TriggerEvent("VideoChanged")
#####################################################################
# Queue Management #
#####################################################################
def Save(self):
"""
Save the current queue into a csv file in the MusicDB State Directory.
Therefor the :meth:`lib.cfg.mdbstate.MDBState.SaveVideoQueue` gets used.
Returns:
*Nothing*
"""
global Queue
global QueueLock
with QueueLock:
self.mdbstate.SaveVideoQueue(Queue)
def Load(self):
"""
This method loads the last stored video queue for the MusicDB State Directory
via :meth:`lib.cfg.mdbstate.MDBState.LoadVideoQueue`.
Returns:
*Nothing*
"""
global Queue
global QueueLock
with QueueLock:
Queue = self.mdbstate.LoadVideoQueue()
def GenerateID(self):
"""
This method generate a unique ID.
In detail, it is a `Version 4 Universally Unique Identifier (UUID) <https://en.wikipedia.org/wiki/Universally_unique_identifier#Version_4_(random)>`_ .
It will be returned as an integer.
This method is build for the internal use in this class.
Returns:
A UUID to be used as entry ID
Example:
.. code-block:: python
queue = VideoQueue()
uuid = queue.GenerateID()
print(type(uuid)) # int
"""
return uuid.uuid4().int
def CurrentVideo(self):
"""
This method returns the current video in the queue.
The method returns element 0 from the queue which is the current video
that can be streamed or gets already streamed.
The video shall remain in the queue until it got completely streamed.
Then it can be removed by calling :meth:`~mdbapi.videoqueue.VideoQueue.NextVideo`.
When the queue is empty, a new random video gets added.
This is the exact same video that then will be returned by this method.
If adding a new video fails, ``None`` gets returned.
This method triggers the ``VideoQueueChanged`` event when the queue was empty and a new random video got added.
Returns:
A dictionary as described in the module description
Example:
.. code-block:: python
queue = VideoQueue()
# Queue will be empty after creating a VideoQueue object
entry = queue.CurrentVideo()
if entry:
print("Random VideoID: %s" % (str(entry["videoid"])))
else
print("Queue is empty! - Adding random video failed!")
# Adds two new video with ID 7357 and 1337.
# Then the current video is the first video added.
queue.AddVideo(7357)
queue.AddVideo(1337)
entry = queue.CurrentVideo()
if entry:
print("VideoID: %s" % (str(entry["videoid"]))) # 7357
else
# will not be reached because we explicitly added videos.
print("Queue is empty! - Adding random videofailed!")
"""
global Queue
global QueueLock
with QueueLock:
# Empty Queue? Add a random video!
if len(Queue) == 0:
self.AddRandomVideo()
self.Event_VideoQueueChanged()
# Still empty (no random video found)? Then return None. Nothing to do…
if len(Queue) == 0:
logging.critical(
"Queue run empty! \033[1;30m(Check constraints for random video selection and check if there are videos at all)"
)
return None
# Select first video from queue
entry = Queue[0]
return entry
def NextVideo(self):
"""
This method returns the next video in the queue.
This entry will be the next current video.
The method pops the last current element from the queue.
Then the new element at position 0, the new current element, will be returned.
If the queue is empty, ``None`` gets returned.
.. warning::
In context of streaming, this method may not be the one you want to call.
This Method drops the current video and sets the next video on top of the queue.
The stream will not notice this, so that it continues streaming the previous video. (See :doc:`/mdbapi/videostream`).
If you want to stream the next video, call :meth:`mdbapi.videostream.VideoStreamManager.PlayNextVideo`.
The :meth:`mdbapi.videostream.VideoStreamManager.PlayNextVideo` then makes the Streaming Thread calling this method.
This method triggers the ``VideoChanged`` and ``VideoQueueChanged`` event when the queue was not empty.
The ``VideoChanged`` event gets also triggered when there was no next video.
When there is only one entry left in the queue - the current video - then a new one gets add via :meth:`AddRandomVideo`
Returns:
The new current video entry in the queue as dictionary described in the module description
Example:
.. code-block:: python
queue = VideoQueue()
# Adds two new video with ID 7357 and 1337.
queue.AddVideo(7357)
queue.AddVideo(1337)
entry = queue.CurrentVideo()
print("VideoID: %s" % (str(entry["videoid"]))) # 7357
entry = queue.NextVideo()
print("VideoID: %s" % (str(entry["videoid"]))) # 1337
entry = queue.CurrentVideo()
print("VideoID: %s" % (str(entry["videoid"]))) # 1337
"""
global Queue
global QueueLock
with QueueLock:
if len(Queue) == 0:
return None
# Get next video
if len(Queue) == 1:
Queue.pop(0)
entry = None
else: # > 1
Queue.pop(0)
entry = Queue[0]
# Make sure the queue never runs empty
if len(Queue) < 2:
self.AddRandomVideo()
self.Event_VideoChanged()
self.Event_VideoQueueChanged()
return entry
def GetQueue(self):
"""
This method returns a copy of the video queue.
The queue is a list of dictionaries.
The content of the dictionary is described in the description of this module.
Returns:
The current video queue. ``[None]`` if there is no queue yet.
Example:
.. code-block:: python
queue = videoqueue.GetQueue()
if not queue:
print("There are no videos in the queue")
else:
for entry in queue:
print("Element with ID %i holds the video with ID %i"
% (entry["entryid"], entry["videoid"]))
"""
global Queue
return list(Queue)
def AddVideo(self, videoid, position="last", israndom=False):
"""
With this method, a new video can be insert into the queue.
The position in the queue, where the video gets insert can be changed by setting the ``position`` argument:
* ``"last"`` (default): Appends the video at the end of the queue
* ``"next"``: Inserts the video right after the current playing video.
* *Integer*: Entry-ID after that the video shall be inserted.
On success, this method triggers the ``VideoQueueChanged`` event.
When the video shall be put at the beginning of the queue, then it gets set to index 1 not index 0.
So the current playing video (index 0) remains!
The new video gets added to the :mod:`~mdbapi.blacklist` via :meth:`mdbapi.blacklist.BlacklistInterface.AddVideo`
The method also triggers the ``VideoQueueChanged`` event.
Args:
videoid (int): The ID of the video that shall be added to the queue
position (str/int): Defines the position where the video gets inserted
israndom (bool): Defines whether the video is randomly selected or not
Returns:
*Nothing*
Raises:
TypeError: When ``videoid`` is not of type ``int``
"""
if type(videoid) is not int:
raise TypeError("Video ID must be an integer!")
entryid = self.GenerateID()
newentry = {}
newentry["entryid"] = entryid
newentry["videoid"] = videoid
newentry["israndom"] = israndom
global Queue
global QueueLock
with QueueLock:
if position == "next":
Queue.insert(1, newentry)
elif position == "last":
Queue.append(newentry)
elif type(position) == int:
for index, entry in enumerate(Queue):
if entry["entryid"] == position:
Queue.insert(index + 1, newentry)
break
else:
logging.warning(
"Queue Entry ID %s does not exist. \033[1;30m(Doing nothing)",
str(position))
else:
logging.warning(
"Position must have the value \"next\" or \"last\" or an Queue Entry ID. Given was \"%s\". \033[1;30m(Doing nothing)",
str(position))
return
# add to blacklist
self.blacklist.AddVideo(videoid)
self.Event_VideoQueueChanged()
return
def AddRandomVideo(self, position="last"):
"""
This method adds a random video into the queue.
The position in the queue, where the video gets insert can be changed by setting the ``position`` argument:
* ``"last"`` (default): Appends the video at the end of the queue
* ``"next"``: Inserts the video right after the current playing video.
The method :meth:`mdbapi.randy.Randy.GetVideo` will be used to get a random video from the activated genres.
After selecting the random video, the :meth:`~AddVideo` method gets used to insert the new video into the queue.
If there is no video found by Randy, then nothing gets added to the queue and ``False`` will be returned.
Args:
position (str): Defines the position where the video gets inserted.
albumid (int/NoneType): ID of the album from that the video will be selected, or ``None`` for selecting a video from the activated genres.
Returns:
``True`` when a random video got added to the queue. Otherwise ``False``.
Raises:
TypeError: When one of the types of the arguments are not correct
"""
if type(position) != str:
raise TypeError("Position must be a string!")
mdbvideo = self.randy.GetVideo()
if not mdbvideo:
return False
self.AddVideo(mdbvideo["id"], position, israndom=True)
return True
def GetVideo(self, entryid):
"""
Returns the video ID of the entry addressed by the entry ID
Args:
entryid (int): ID of the entry that video ID shall be returned
Returns:
The video ID of the entry, or ``None`` if the entry does not exists
Raises:
TypeError: When ``entryid`` is not of type ``int``
"""
if type(entryid) is not int:
raise TypeError("Entry ID must be an integer!")
global Queue
global QueueLock
with QueueLock:
for entry in Queue:
if entry["entryid"] == entryid:
return entry["videoid"]
logging.debug(
"Cannot find the requested entry %s! \033[1;30m(Returning None)",
str(entryid))
return None
def RemoveVideo(self, entryid):
"""
Removes the entry with the ID ``entryid`` from the queue.
Removing the current video is not allowed!
Call :meth:`~NextVideo` instead.
When there is only one entry left in the queue - the current video - then a new one gets add via :meth:`~AddRandomVideo`
On success, this method triggers the ``VideoQueueChanged`` event.
Args:
entryid (int): Entry to remove
Returns:
``True`` on success, otherwise ``False``
Raises:
TypeError: When ``entryid`` is not of type ``int``
"""
if type(entryid) is not int:
raise TypeError("Entry ID must be an integer!")
global Queue
global QueueLock
with QueueLock:
if len(Queue) < 2:
logging.warning(
"The queue has only %i element. There must be at least 2 entries to be able to remove one.",
len(Queue))
return False
if Queue[0]["entryid"] == entryid:
logging.warning(
"The entry ID addresses the current video. This entry cannot be removed!"
)
return False
Queue = [entry for entry in Queue if entry["entryid"] != entryid]
# Make sure the queue never runs empty
if len(Queue) < 2:
self.AddRandomVideo()
self.Event_VideoQueueChanged()
return True
def MoveVideo(self, entryid, afterid):
"""
This method moves an entry, addressed by ``entryid`` behind another entry addressed by ``afterid``.
If both IDs are the same, the method returns immediately without doing anything.
When ``entryid`` addresses the current video, the method returns with value ``False``
On success, the method triggers the ``VideoQueueChanged`` event.
Args:
entryid (int):
afterid (int):
Returns:
``True`` when the entry was moved, otherwise ``False``
Raises:
TypeError: When ``entryid`` or ``afterid`` is not of type int
"""
if entryid == afterid:
return False
# First check, if everything is OK with the arguments
if type(entryid) is not int or type(afterid) is not int:
raise TypeError("Queue entry IDs must be of type int!")
global Queue
global QueueLock
with QueueLock:
if Queue[0]["entryid"] == entryid:
logging.warning(
"The entry ID addresses the current video. This entry cannot be moved!"
)
return False
# Get Positions
frompos = [
pos for pos, entry in enumerate(Queue)
if entry["entryid"] == entryid
]
topos = [
pos for pos, entry in enumerate(Queue)
if entry["entryid"] == afterid
]
if not frompos:
logging.warning(
"Cannot find element with entryid %i in the queue!\033[1;30m (Doing nothing)",
entryid)
return False
if not topos:
logging.warning(
"Cannot find element with afterid %i in the queue!\033[1;30m (Doing nothing)",
afterid)
return False
frompos = frompos[0]
topos = topos[0]
# When topos is behind frompos, decrement topos because if shifts one entry down due to popping the frompos-element from the list
if topos < frompos:
topos += 1
# Move element
entry = Queue.pop(frompos)
Queue.insert(topos, entry)
self.Event_VideoQueueChanged()
return True
class Randy(object):
"""
This class provides methods to get a random song under certain constraints.
Args:
config: :class:`~lib.cfg.musicdb.MusicDBConfig` object holding the MusicDB Configuration
database: A :class:`~lib.db.musicdb.MusicDatabase` instance
Raises:
TypeError: When the arguments are not of the correct type.
"""
def __init__(self, config, database):
if type(config) != MusicDBConfig:
raise TypeError("config argument not of type MusicDBConfig")
if type(database) != MusicDatabase:
raise TypeError("database argument not of type MusicDatabase")
self.db = database
self.cfg = config
self.mdbstate = MDBState(self.cfg.server.statedir, self.db)
self.blacklist = BlacklistInterface(self.cfg, self.db)
# Load most important keys
self.nodisabled = self.cfg.randy.nodisabled
self.nohated = self.cfg.randy.nohated
self.minlen = self.cfg.randy.minsonglen
def GetSong(self):
"""
This method chooses a random song in a two-stage process as described in the module description.
Returns:
A song from the :class:`~lib.db.musicdb.MusicDatabase` or ``None`` if an error occurred.
"""
global BlacklistLock
global Blacklist
filterlist = self.mdbstate.GetFilterList()
if not filterlist:
logging.warning(
"No Genre selected! \033[1;30m(Selecting random song from the whole collection)"
)
# Get Random Song - this may take several tries
logging.debug("Randy starts looking for a random song …")
t_start = datetime.datetime.now()
song = None
while not song:
# STAGE 1: Get Mathematical random song (under certain constraints)
try:
song = self.db.GetRandomSong(filterlist, self.nodisabled,
self.nohated, self.minlen)
except Exception as e:
logging.error("Getting random song failed with error: \"%s\"!",
str(e))
return None
if not song:
logging.error(
"There is no song fulfilling the constraints! \033[1;30m(Check the stage 1 constraints)"
)
return None
logging.debug("Candidate for next song: \033[0;35m" + song["path"])
# GetRandomSong only looks for album genres.
# The song genre may be different and not in the set of the filerlist.
try:
songgenres = self.db.GetTargetTags(
"song", song["id"], MusicDatabase.TAG_CLASS_GENRE)
# Create a set of tagnames if there are tags for this song.
# Ignore AI set tags because they may be wrong
if songgenres:
tagnames = {
songgenre["name"]
for songgenre in songgenres
if songgenre["approval"] >= 1
}
else:
tagnames = {}
# If the tag name set was successfully created, compare it with the selected genres
if tagnames:
if not tagnames & set(filterlist):
logging.debug(
"song is of different genre than album and not in activated genres. (Song genres: %s)",
str(tagnames))
song = None
continue
except Exception as e:
logging.error("Song tag check failed with exception: \"%s\"!",
str(e))
return None
# STAGE 2: Make randomness feeling random by checking if the song was recently played
if self.blacklist.CheckAllLists(song):
song = None
continue
# New song found \o/
t_stop = datetime.datetime.now()
logging.debug("Randy found the following song after %s : \033[0;36m%s",
str(t_stop - t_start), song["path"])
return song
def GetSongFromAlbum(self, albumid):
"""
Get a random song from a specific album.
If the selected song is listed in the blacklist for songs, a new one will be selected.
Entries in the album and artist blacklist will be ignored because the artist and album is forced by the user.
But the song gets added to the blacklist for songs, as well as the album and artist gets added.
The genre of the song gets completely ignored.
The user wants to have a song from the given album, so it gets one.
.. warning::
This is a dangerous method.
An album only has a very limited set of songs.
If all the songs are listed in the blacklist, the method would get caught in an infinite loop.
To avoid this, there are only 10 tries to find a random song.
If after the tenth try, the method leaves returning ``None``
Args:
albumid (int): ID of the album the song shall come from
Returns:
A song from the :class:`~lib.db.musicdb.MusicDatabase` or ``None`` if an error occurred.
"""
global BlacklistLock
global Blacklist
# Get parameters
song = None
tries = 0 # there is just a very limited set of possible songs. Avoid infinite loop when all songs are on the blacklist
while not song and tries <= 10:
tries += 1
# STAGE 1: Get Mathematical random song (under certain constraints)
try:
song = self.db.GetRandomSong(None, self.nodisabled,
self.nohated, self.minlen,
albumid)
except Exception as e:
logging.error("Getting random song failed with error: \"%s\"!",
str(e))
return None
logging.debug("Candidate for next song: \033[0;35m" + song["path"])
# STAGE 2: Make randomness feeling random by checking if the song was recently played
# only check, if that song is in the blacklist. Artist and album is forced by the user
if self.blacklist.CheckSongList(song):
song = None
continue
if not song:
logging.warning(
"The loop that should find a new random song did not deliver a song! \033[1;30m(This happens when there are too many songs of the given album are already on the blacklist)"
)
return None
# Add song to queue
logging.debug(
"Randy adds the following song after %s tries: \033[0;36m%s",
tries, song["path"])
return song