Merge pull request #514 from ncoop/mpris-api

Add DBus callbacks to now_playing

i3pystatus/now_playing.py

@@ -1,5 +1,3 @@
-
-import functools
 from os.path import basename
 
 import dbus
@@ -8,28 +6,69 @@ from i3pystatus import IntervalModule, formatp
 from i3pystatus.core.util import TimeWrapper
 
 
+class Dbus:
+    obj_dbus = "org.freedesktop.DBus"
+    path_dbus = "/org/freedesktop/DBus"
+    obj_player = "org.mpris.MediaPlayer2"
+    path_player = "/org/mpris/MediaPlayer2"
+    intf_props = obj_dbus + ".Properties"
+    intf_player = obj_player + ".Player"
+
+
 class NoPlayerException(Exception):
     pass
 
 
 class NowPlaying(IntervalModule):
     """
-    Shows currently playing track information, supports most media players
+    Shows currently playing track information. Supports media players that \
+conform to the Media Player Remote Interfacing Specification.
 
-    * Requires python-dbus available from every distros' package manager.
+    * Requires ``python-dbus`` from your distro package manager, or \
+``dbus-python`` from PyPI.
 
-    Left click on the module play/pauses, right click goes to the next track.
+    Left click on the module to play/pause, and right click to go to the next \
+track.
 
     .. rubric:: Available formatters (uses :ref:`formatp`)
 
     * `{title}` — (the title of the current song)
-    * `{album}` — (the album of the current song, can be an empty string (e.g. for online streams))
+    * `{album}` — (the album of the current song, can be an empty string \
+(e.g. for online streams))
     * `{artist}` — (can be empty, too)
-    * `{filename}` — (file name with out extension and path; empty unless title is empty)
+    * `{filename}` — (file name with out extension and path; empty unless \
-    * `{song_elapsed}` — (position in the currently playing song, uses :ref:`TimeWrapper`, default is `%m:%S`)
+title is empty)
+    * `{song_elapsed}` — (position in the currently playing song, uses \
+:ref:`TimeWrapper`, default is `%m:%S`)
     * `{song_length}` — (length of the current song, same as song_elapsed)
     * `{status}` — (play, pause, stop mapped through the `status` dictionary)
     * `{volume}` — (volume)
+
+    .. rubric:: Available callbacks
+
+    * ``playpause`` — Plays if paused or stopped, otherwise pauses.
+    * ``next_song`` — Goes to next track in the playlist.
+    * ``player_command`` — Invoke a command with the `MediaPlayer2.Player` \
+interface. The method name and its arguments are appended as list elements.
+    * ``player_prop`` — Get or set a property of the `MediaPlayer2.Player` \
+interface. Append the property name to get, or the name and a value to set.
+
+    `MediaPlayer2.Player` methods and properties are documented at \
+https://specifications.freedesktop.org/mpris-spec/latest/Player_Interface.html
+
+    Your player may not support the full interface.
+
+    Example module registration with callbacks:
+
+    ::
+
+        status.register("now_playing",
+            on_leftclick=["player_command", "PlayPause"],
+            on_rightclick=["player_command", "Stop"],
+            on_middleclick=["player_prop", "Shuffle", True],
+            on_upscroll=["player_command", "Seek", -10000000],
+            on_downscroll=["player_command", "Seek", +10000000])
+
     """
 
     interval = 1
@@ -69,11 +108,11 @@ class NowPlaying(IntervalModule):
     old_player = None
 
     def find_player(self):
-        obj = dbus.SessionBus().get_object("org.freedesktop.DBus", "/org/freedesktop/DBus")
+        obj = dbus.SessionBus().get_object(Dbus.obj_dbus, Dbus.path_dbus)
 
         def get_players(methodname):
-            method = obj.get_dbus_method(methodname, 'org.freedesktop.DBus')
+            method = obj.get_dbus_method(methodname, Dbus.obj_dbus)
-            return [a for a in method() if a.startswith("org.mpris.MediaPlayer2.")]
+            return [a for a in method() if a.startswith(Dbus.obj_player + ".")]
 
         players = get_players('ListNames')
         if not players:
@@ -87,45 +126,51 @@ class NowPlaying(IntervalModule):
 
     def get_player(self):
         if self.player:
-            player = "org.mpris.MediaPlayer2." + self.player
+            player = Dbus.obj_player + "." + self.player
             try:
-                return dbus.SessionBus().get_object(player, "/org/mpris/MediaPlayer2")
+                return dbus.SessionBus().get_object(player, Dbus.path_player)
             except dbus.exceptions.DBusException:
                 raise NoPlayerException()
         else:
             player = self.find_player()
-            return dbus.SessionBus().get_object(player, "/org/mpris/MediaPlayer2")
+            return dbus.SessionBus().get_object(player, Dbus.path_player)
 
     def run(self):
         try:
             player = self.get_player()
-            properties = dbus.Interface(player, "org.freedesktop.DBus.Properties")
+            properties = dbus.Interface(player, Dbus.intf_props)
 
             def get_prop(name, default=None):
                 try:
-                    return properties.Get("org.mpris.MediaPlayer2.Player", name)
+                    return properties.Get(Dbus.intf_player, name)
                 except dbus.exceptions.DBusException:
                     return default
 
             currentsong = get_prop("Metadata")
 
             fdict = {
-                "status": self.status[self.statusmap[get_prop("PlaybackStatus")]],
+                "status": self.status[self.statusmap[
-                "len": 0,  # TODO: Use optional(!) TrackList interface for this to gain 100 % mpd<->now_playing compat
+                    get_prop("PlaybackStatus")]],
+                # TODO: Use optional(!) TrackList interface for this to
+                # gain 100 % mpd<->now_playing compat
+                "len": 0,
                 "pos": 0,
                 "volume": int(get_prop("Volume", 0) * 100),
 
                 "title": currentsong.get("xesam:title", ""),
                 "album": currentsong.get("xesam:album", ""),
                 "artist": ", ".join(currentsong.get("xesam:artist", "")),
-                "song_length": TimeWrapper((currentsong.get("mpris:length") or 0) / 1000 ** 2),
+                "oong_length": TimeWrapper((currentsong.get("mpris:length") or
-                "song_elapsed": TimeWrapper((get_prop("Position") or 0) / 1000 ** 2),
+                                            0) / 1000 ** 2),
+                "song_elapsed": TimeWrapper((get_prop("Position") or 0) /
+                                            1000 ** 2),
                 "filename": "",
             }
 
             if not fdict["title"]:
                 fdict["filename"] = '.'.join(
-                    basename((currentsong.get("xesam:url") or "")).split('.')[:-1])
+                    basename((currentsong.get("xesam:url") or "")).
+                    split('.')[:-1])
 
             self.data = fdict
             self.output = {
@@ -159,7 +204,7 @@ class NowPlaying(IntervalModule):
 
     def playpause(self):
         try:
-            dbus.Interface(self.get_player(), "org.mpris.MediaPlayer2.Player").PlayPause()
+            dbus.Interface(self.get_player(), Dbus.intf_player).PlayPause()
         except NoPlayerException:
             return
         except dbus.exceptions.DBusException:
@@ -167,7 +212,29 @@ class NowPlaying(IntervalModule):
 
     def next_song(self):
         try:
-            dbus.Interface(self.get_player(), "org.mpris.MediaPlayer2.Player").Next()
+            dbus.Interface(self.get_player(), Dbus.intf_player).Next()
+        except NoPlayerException:
+            return
+        except dbus.exceptions.DBusException:
+            return
+
+    def player_command(self, command, *args):
+        try:
+            interface = dbus.Interface(self.get_player(), Dbus.intf_player)
+            getattr(interface, command)(*args)
+        except NoPlayerException:
+            return
+        except dbus.exceptions.DBusException:
+            return
+
+    def player_prop(self, name, value=None):
+        try:
+            properties = dbus.Interface(self.get_player(), Dbus.intf_props)
+            # None/null/nil implies get because it's not a valid DBus datatype.
+            if value is None:
+                return properties.Get(Dbus.intf_player, name)
+            else:
+                properties.Set(Dbus.intf_player, name, value)
         except NoPlayerException:
             return
         except dbus.exceptions.DBusException: