Do not automatically start worker thread and connect in Chromecast constructor (#271)

* Add defer_connect option to Chromecast class constructor

* Lint

* Do not connect or start thread in socket_client constructor

* Fix non-blocking mode, update examples

* Start worker thread from Chromecast.wait()

* Lint

* Lint

Author: emontnemery

README.rst

@@ -39,7 +39,7 @@ How to use
     ['Dev', 'Living Room', 'Den', 'Bedroom']
 
     >> cast = next(cc for cc in chromecasts if cc.device.friendly_name == "Living Room")
-    >> # Wait for cast device to be ready
+    >> # Start worker thread and wait for cast device to be ready
     >> cast.wait()
     >> print(cast.device)
     DeviceStatus(friendly_name='Living Room', model_name='Chromecast', manufacturer='Google Inc.', uuid=UUID('df6944da-f016-4cb8-97d0-3da2ccaa380b'), cast_type='cast')

examples/blocking.py

@@ -19,6 +19,7 @@
     print("No Devices Found")
     exit()
 cast = casts[0]
+cast.start()
 
 print()
 print(cast.device)

examples/dashcast_blocking.py

@@ -21,6 +21,7 @@
     exit()
 
 cast = casts[0]
+cast.start()
 
 d = dashcast.DashCastController()
 cast.register_handler(d)

examples/non_blocking.py

@@ -20,6 +20,7 @@ def your_main_loop():
     t = 1
     cast = None
     def callback(chromecast):
+        chromecast.connect()
         nonlocal cast
         cast = chromecast
         stop_discovery()

examples/simple_listener_example.py

@@ -30,6 +30,7 @@ def new_media_status(self, status):
 chromecasts = pychromecast.get_chromecasts()
 chromecast = next(cc for cc in chromecasts
                   if cc.device.friendly_name == "Living Room Speaker")
+chromecast.start()
 
 listenerCast = StatusListener(chromecast.name, chromecast)
 chromecast.register_status_listener(listenerCast)

examples/spotify_example.py

@@ -13,6 +13,7 @@
 
 chromecasts = pychromecast.get_chromecasts()
 cast = chromecasts[0]
+cast.start()
 
 CAST_NAME = "My Chromecast"
 device_id = None

pychromecast/__init__.py

@@ -119,7 +119,7 @@ def internal_stop():
         return internal_stop
 
 
-# pylint: disable=too-many-instance-attributes
+# pylint: disable=too-many-instance-attributes, too-many-public-methods
 class Chromecast(object):
     """
     Class to interface with a ChromeCast.
@@ -206,9 +206,6 @@ def __init__(self, host, port=None, device=None, **kwargs):
         self.register_connection_listener = \
             self.socket_client.register_connection_listener
 
-        if blocking:
-            self.socket_client.start()
-
     @property
     def ignore_cec(self):
         """ Returns whether the CEC data should be ignored. """
@@ -320,15 +317,26 @@ def wait(self, timeout=None):
         Waits until the cast device is ready for communication. The device
         is ready as soon a status message has been received.
 
+        If the worker thread is not already running, it will be started.
+
         If the status has already been received then the method returns
         immediately.
 
         :param timeout: a floating point number specifying a timeout for the
                         operation in seconds (or fractions thereof). Or None
                         to block forever.
         """
+        if not self.socket_client.isAlive():
+            self.socket_client.start()
         self.status_event.wait(timeout=timeout)
 
+    def connect(self):
+        """ Connect to the chromecast.
+
+            Must only be called if the worker thread will not be started.
+        """
+        self.socket_client.connect()
+
     def disconnect(self, timeout=None, blocking=True):
         """
         Disconnects the chromecast and waits for it to terminate.
@@ -354,6 +362,12 @@ def join(self, timeout=None):
         """
         self.socket_client.join(timeout=timeout)
 
+    def start(self):
+        """
+        Start the chromecast connection's worker thread.
+        """
+        self.socket_client.start()
+
     def __del__(self):
         try:
             self.socket_client.stop.set()

pychromecast/socket_client.py

@@ -212,14 +212,6 @@ def __init__(self, host, port=None, cast_type=CAST_TYPE_CHROMECAST,
 
         self.receiver_controller.register_status_listener(self)
 
-        try:
-            self.initialize_connection()
-        except ChromecastConnectionError:
-            self._report_connection_status(
-                ConnectionStatus(CONNECTION_STATUS_DISCONNECTED,
-                                 NetworkAddress(self.host, self.port)))
-            raise
-
     def initialize_connection(self):  # noqa: E501 pylint:disable=too-many-statements, too-many-branches
         """Initialize a socket to a Chromecast, retrying as necessary."""
         tries = self.tries
@@ -361,6 +353,19 @@ def mdns_backoff(service, retry):
                           self.fn or self.host, self.port)
         raise ChromecastConnectionError("Failed to connect")
 
+    def connect(self):
+        """ Connect socket connection to Chromecast device.
+
+            Must only be called if the worker thread will not be started.
+        """
+        try:
+            self.initialize_connection()
+        except ChromecastConnectionError:
+            self._report_connection_status(
+                ConnectionStatus(CONNECTION_STATUS_DISCONNECTED,
+                                 NetworkAddress(self.host, self.port)))
+            return
+
     def disconnect(self):
         """ Disconnect socket connection to Chromecast device """
         self.stop.set()
@@ -413,7 +418,15 @@ def is_stopped(self):
         return self.stop.is_set()
 
     def run(self):
-        """ Start polling the socket. """
+        """ Connect to the cast and start polling the socket. """
+        try:
+            self.initialize_connection()
+        except ChromecastConnectionError:
+            self._report_connection_status(
+                ConnectionStatus(CONNECTION_STATUS_DISCONNECTED,
+                                 NetworkAddress(self.host, self.port)))
+            return
+
         self.heartbeat_controller.reset()
         self._force_recon = False
         logging.debug("Thread started...")
@@ -698,8 +711,8 @@ def send_message(self, destination_id, namespace, data,
                 self.logger.info('[%s:%s] Error writing to socket.',
                                  self.fn or self.host, self.port)
         else:
-            raise NotConnected("Chromecast " + self.host + ":" + self.port +
-                               " is connecting...")
+            raise NotConnected("Chromecast " + self.host + ":" +
+                               str(self.port) + " is connecting...")
 
     def send_platform_message(self, namespace, message, inc_session_id=False,
                               callback_function_param=False):