66 lines
2.4 KiB
ReStructuredText
66 lines
2.4 KiB
ReStructuredText
About
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========
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What does it do
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---------------
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larigira integrates with MPD (Music Player Daemon) and prevents your playlist
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from running empty. It also has powerful support for "events": audio that must be played at some time.
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Features
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---------
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* Simple to install
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* WebUI
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* modular event system
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Architecture
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-------------
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larigira delegates all the music playing business to MPD.
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It relies on ``tinydb`` as a db: it's actually just a json file, to achieve
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simplicity and flexibility.
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Code structure and core concepts
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-----------------------------------
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The code is heavily based on gevent: almost everything is a greenlet.
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alarm
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An alarm is a specification of timings. It is "something that can generate
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times". For example ``{ 'kind': 'single', 'timestamp': 1234567890 }``
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generates a single time (February 14, 2009 00:31:00), while
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``{ 'kind': 'frequency', 'interval': 10, 'start': 1234567890 }`` generates
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infinite times, one every 10 seconds, starting from February 14, 2009
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00:31:00.
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action
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An action is a specification of audio. It is "something that can generate a
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list of audio files".
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For example, ``{ 'kind': 'randomdir', 'paths': ['/my/dir', '/other/path'] }``
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will pick a random file from one of the two paths.
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event
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An event is an alarm plus a list of actions. At given times, do those things
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The main object is :class:`larigira.mpc.Player`; as the name says, it is the only object that sends messages
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to MPD. How does it know what to do? there are two main flows: the continous playlist filling and the alarm
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system.
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Continous playlist
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~~~~~~~~~~~~~~~~~~
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:class:`larigira.mpc.Player` has a "child" called :class:`larigira.mpc.MpcWatcher`. It watches for events on
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the playlist; when the playlist is changed it notifies Player, which in turn will check if the playlist has
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enough songs. If that's the case, it will spawn an audiogenerator in a new greenlet; when the audio will be
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ready, it will be added at the bottom of the playlist.
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Alarm system
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~~~~~~~~~~~~
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There is a DB. The lowest level is handled by TinyDB. :class:`larigira.event.EventModel` is a thin layer on
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it, providing more abstract functions. The real deal is :class:`larigira.event.EventSource`, which is a
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greenlet that sends notifications about alarms in the DB. Those notifications are received by
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:class:`larigira.event.Monitor`, which "runs" them; it executes the time specification, make an appropriate
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"sleep" and after that runs the audiogenerator.
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