Create PlayLog, move tag identification into MediaLibrary

jukebox/library/file-backend.js

@@ -1,6 +1,7 @@
 "use strict";
 
 const glob = require('glob');
+const basename = require('path').basename;
 
 class FileBackend {
   constructor(config) {
@@ -10,8 +11,9 @@ class FileBackend {
   find(tag, callback) {
     glob('media/' + tag + ' - *.mp3', (err, files) => {
       if (files.length > 0) {
-        callback(files[0]);
+        callback(basename(files[0]));
       }
+      callback();
     });
   }
 }

jukebox/library/index.js

@@ -1,70 +1,34 @@
 "use strict";
 
 const EventEmitter = require('events').EventEmitter;
+const tags = require('./tags');
 
 class Library extends EventEmitter {
   constructor(config, backend) {
     super();
 
-    this.log_size = 10;
     this.config = config;
     this.backend = backend;
-    this.log = [];
   }
 
   find(tag) {
+    if (tag === this.config.stop_id) {
+      this.emit('action', new tags.StopCommand());
+    }
+
+    if (tag === this.config.pause_id) {
+      this.emit('action', new tags.PauseCommand());
+    }
+
     this.backend.find(tag, path => {
       if (!path) {
-        this.updateLog(new NotFoundLogEntry(tag));
+        this.emit('action', new tags.NotFoundTag(tag));
         return;
       }
 
-      this.updateLog(new FileLogEntry(tag, path));
+      this.emit('action', new tags.FileTag(tag, path));
     });
   }
-
-  updateLog(entry) {
-    this.log.unshift(entry);
-    if (this.log.length > this.log_size) {
-      this.log.pop();
-    }
-    this.emit('play', entry);
-  }
-
-  getLastTag() {
-    if (this.log.length == 0) {
-      return;
-    }
-
-    return this.log[0].tag;
-  }
-
-  getLog() {
-    return this.log;
-  }
-}
-
-class LogEntry {
-  constructor(tag) {
-    this.tag = tag;
-  }
-
-  toString() {
-    return this.tag;
-  }
-}
-
-class NotFoundLogEntry extends LogEntry {
-  toString() {
-    return `Unknown media: ${this.tag}`
-  }
-}
-
-class FileLogEntry extends LogEntry {
-  constructor(tag, path) {
-    super(tag);
-    this.path = path;
-  }
 }
 
 module.exports.Library = Library;

jukebox/library/play-log.js

@@ -0,0 +1,44 @@
+"use strict";
+
+const EventEmitter = require('events').EventEmitter;
+
+const tags = require('./tags');
+
+module.exports.PlayLog = class PlayLog extends EventEmitter {
+  constructor() {
+    super();
+    this.last_tag = undefined;
+    this.log = [];
+    this.log_size = 10;
+  }
+
+  updateLog(tag) {
+    this.last_tag = tag;
+
+    if (tag instanceof tags.NotFoundTag) {
+      this.emit('update', tag);
+      return;
+    }
+
+    this.log.unshift(tag);
+    if (this.log.length > this.log_size) {
+      this.log.pop();
+    }
+
+    this.emit('update', tag);
+  }
+
+  getLastTag() {
+    if (this.log.length == 0) {
+      return;
+    }
+
+    return this.log[0].tag;
+  }
+
+  getLog() {
+    return this.log;
+  }
+}
+
+// vim:ts=2 sw=2 et:

jukebox/library/tags.js

@@ -0,0 +1,45 @@
+class Tag {
+  constructor(tag) {
+    this.tag = tag;
+  }
+
+  toString() {
+    return this.tag;
+  }
+}
+
+class StopCommand extends Tag {
+    toString() {
+        return "Command: STOP";
+    }
+}
+
+class PauseCommand extends Tag {
+    toString() {
+        return "Command: PAUSE";
+    }
+}
+
+class NotFoundTag extends Tag {
+  toString() {
+    return `Unknown tag: ${this.tag}`
+  }
+}
+
+class FileTag extends Tag {
+  constructor(tag, path) {
+    super(tag);
+    this.path = path;
+  }
+
+  toString() {
+    return this.path;
+  }
+}
+
+module.exports = {
+    StopCommand: StopCommand
+    , PauseCommand: PauseCommand
+    , NotFoundTag: NotFoundTag
+    , FileTag: FileTag
+};

jukebox/media-player.js

@@ -1,11 +1,14 @@
 "use strict";
 
+const tags = require('./library/tags');
+
 const throttle = require('throttle-debounce/throttle');
 
 const ChildProcessEmitter = require('./child-process').ChildProcessEmitter;
 
 const DEFAULT_PAUSE_THROTTLE = 2000;
 const DEFAULT_PLAY_THROTTLE = 5000;
+const DEFAULT_UNKNOWN_THROTTLE = 2000;
 
 class MediaPlayer extends ChildProcessEmitter {
   constructor(config, logger) {
@@ -23,6 +26,8 @@ class MediaPlayer extends ChildProcessEmitter {
       this._playFile(path);
     });
 
+    this.unknown = throttle(config.unknown_throttle || DEFAULT_UNKNOWN_THROTTLE, this._unknown);
+
     // default to unthrottled
     this.pause = this._pauseFile;
     this.playFile = this._playFile;
@@ -33,16 +38,35 @@ class MediaPlayer extends ChildProcessEmitter {
     this.playFile = this.playFileThrottled;
   }
 
-  stop() {
+  stop(tag) {
+    this.emit('command', tag);
     this.send('STOP');
   }
 
-  _pause() {
+  _pause(tag) {
+    this.emit('command', tag);
     this.send('PAUSE');
   }
 
-  _playFile(path) {
-    this.send("LOAD " + path);
+  _playFile(tag) {
+    this.emit('command', tag);
+    this.send("LOAD media/" + tag.path);
+  }
+
+  _unknown(tag) {
+    this.emit('command', tag);
+  }
+
+  handleTag(tag) {
+    if (tag instanceof tags.StopCommand) {
+      this.stop(tag);
+    } else if (tag instanceof tags.PauseCommand) {
+      this.pause(tag);
+    } else if (tag instanceof tags.FileTag) {
+      this.playFile(tag);
+    } else {
+      this.unknown(tag);
+    }
   }
 }
 

jukebox/tag-reader.js

@@ -3,9 +3,9 @@
 const ChildProcessEmitter = require('./child-process').ChildProcessEmitter;
 
 class TagReader extends ChildProcessEmitter {
-    constructor(config, logger) {
-      super(config.tag_reader, logger);
-    }
+  constructor(config, logger) {
+    super(config.tag_reader, logger);
+  }
 }
 
 module.exports = function(config, logger) {

player.js

@@ -22,6 +22,9 @@ logger.level = config.debug ? 'debug' : 'info';
 
 const MediaPlayer = require('./jukebox/media-player')(config, logger);
 const TagReader = require('./jukebox/tag-reader')(config, logger);
+const play_log = require('./jukebox/library/play-log');
+
+const PlayLog = new play_log.PlayLog();
 
 MediaPlayer.throttle();
 
@@ -36,6 +39,9 @@ function exitHandler(options, err) {
   logger.debug('closing child tasks');
   if (err) logger.debug(err.stack);
 
+  // FIXME When do we actually need to call this? Adding these seems
+  // to have fixed a problem with orphaned children, but not we get
+  // two sets of "closing child tasks" messages when we shut down.
   TagReader.kill();
   MediaPlayer.kill();
 
@@ -57,28 +63,20 @@ if (config.debug) {
   });
 }
 
-MediaLibrary.on('play', event => {
+MediaPlayer.on('command', tag => {
+  PlayLog.updateLog(tag);
+});
+
+PlayLog.on('update', tag => {
   var data = {
-    html: views.log.render({ play_log: MediaLibrary.getLog() }),
-    tag: MediaLibrary.getLastTag()
+    html: views.log.render({ play_log: PlayLog.getLog() }),
+    tag: tag.tag
   };
 
   wss.broadcast(JSON.stringify(data));
 });
 
-MediaLibrary.on('play', event => {
-  if (event.tag === config.stop_id) {
-    MediaPlayer.stop();
-  }
-
-  if (event.tag === config.pause_id) {
-    MediaPlayer.pause();
-  }
-
-  if (event.path) {
-    MediaPlayer.playFile(event.path);
-  }
-});
+MediaLibrary.on('action', MediaPlayer.handleTag.bind(MediaPlayer));
 
 app.use(morgan('dev'))
 app.use(express.static(__dirname + '/static'))
@@ -86,9 +84,9 @@ app.use(express.static(__dirname + '/static'))
 app.get('/', function (req, res, next) {
   try {
     var index = views.index.render({
-      last_tag: MediaLibrary.getLastTag()
+      last_tag: PlayLog.getLastTag()
       , config: config
-      , play_log: MediaLibrary.getLog()
+      , play_log: PlayLog.getLog()
     });
 
     var html = views.base.render({