feat: add function to check if spotify is running

spotifyctl.py

@@ -31,30 +31,59 @@ class NoActiveTrackException(RuntimeError):
     """
 
 
-def _get_spotify_dbus_obj():
-    """Gets the spotify object from the current dbus session bus.
+_SPOTIFY_BUS_NAME = "org.mpris.MediaPlayer2.spotify"
+_SPOTIFY_BUS_PLAYER_OBJECT_PATH = "/org/mpris/MediaPlayer2"
+
+
+def spotify_is_running():
+    """Checks whether the spotify executable is running.
+
+    This is done by checking whether the spotify bus is advertised as available
+    by dbus.
 
     Returns
     -------
-    `spotify_dbus_object` : (dbus.proxies.ProxyObject)[https://dbus.freedesktop.org/doc/dbus-python/dbus.proxies.html#dbus.proxies.ProxyObject]
+    `True`
+        If spotify is running.
+    `False`
+        If spotify is not running.
+    """
+
+    # Connect to the session bus
+    session_bus = dbus.SessionBus()
+
+    # Check if spotify is in the list of clients
+    return _SPOTIFY_BUS_NAME in session_bus.list_names()
+
+
+def _get_spotify_dbus_obj():
+    """Gets the spotify player object from the spotify bus.
+
+    Returns
+    -------
+    `spotify_player_dbus_object` : (dbus.proxies.ProxyObject)[https://dbus.freedesktop.org/doc/dbus-python/dbus.proxies.html#dbus.proxies.ProxyObject]
         A dbus-python proxy object for the spotify dbus object.
 
     Raises
     ------
     `SpotifyNotRunningException`
-        When dbus fails to locate the spotify object.
+        When the spotify executable is not running.
     """
 
+    # Connect to the session bus
     session_bus = dbus.SessionBus()
-    bus_data = ("org.mpris.MediaPlayer2.spotify", "/org/mpris/MediaPlayer2")
-    try:
-        spotify_dbus_object = session_bus.get_object(*bus_data)
-    except dbus.exceptions.DBusException as e:
-        raise SpotifyNotRunningException(
-            "The spotify executable is not running."
-        ) from e
 
-    return spotify_dbus_object
+    if not spotify_is_running():
+        raise SpotifyNotRunningException(
+            "Failed to connect to the spotify bus: Spotify not running."
+        )
+    
+    # Get and return the proxy object for the spotify player dbus object
+    return session_bus.get_object(
+        _SPOTIFY_BUS_NAME,
+        _SPOTIFY_BUS_PLAYER_OBJECT_PATH
+    )
+
 
 
 def _get_interface(interface_name):