Simplified backend interface, fixed some bugs with response management

platypush/__init__.py

@@ -58,6 +58,7 @@ def _init_plugin(plugin_name, reload=False):
 
 
 def _exec_func(args, backend=None, retry=True):
+    origin = args.pop('origin') if 'origin' in args else None
     action = args.pop('action')
     tokens = action.split('.')
     module_name = str.join('.', tokens[:-1])
@@ -79,14 +80,14 @@ def _exec_func(args, backend=None, retry=True):
         response = Response(output=None, errors=[e, traceback.format_exc()])
         logging.exception(e)
         if retry:
-            # Put the action back where it was before retrying
-            args['action'] = action
+            # Put the popped args back where they were before retrying
+            args['action'] = action; args['origin'] = origin
 
             logging.info('Reloading plugin {} and retrying'.format(module_name))
             _init_plugin(module_name, reload=True)
             _exec_func(args, backend, retry=False)
     finally:
-        if backend: backend.send_msg({ 'response':str(response) })
+        if backend: backend.send_response(origin, response)
 
 
 def on_msg(msg, backend=None):

platypush/backend/__init__.py

@@ -1,3 +1,4 @@
+import json
 import logging
 import sys
 import platypush
@@ -53,6 +54,10 @@ class Backend(Thread):
         if target != self.device_id and not self.is_local():
             return  # Not for me
 
+        if 'response' in msg:
+            logging.info('Received response: {}'.format(msg))
+            return
+
         if 'action' not in msg:
             self.on_error('No action specified: {}'.format(msg))
             return
@@ -60,7 +65,24 @@ class Backend(Thread):
         self.mq.put(msg)
 
     def send_msg(self, msg):
-        raise NotImplementedError()
+        if isinstance(msg, str):
+            msg = json.loads(msg)
+        if not isinstance(msg, dict):
+            raise RuntimeError('send_msg expects either a JSON string or ' +
+                               'a dictionary but received {}'.format(type(msg)))
+
+        msg['origin'] = self.device_id  # To get the response
+
+        self._send_msg(msg)
+
+    def send_response(self, target, response):
+        self.send_msg({
+            'target'     : target,
+            'response'   : {
+                'output' : response.output,
+                'errors' : response.errors,
+            }
+        })
 
     def run(self):
         raise NotImplementedError()

platypush/backend/kafka/__init__.py

@@ -9,7 +9,7 @@ class KafkaBackend(Backend):
     def _init(self, server, topic):
         self.server = server
         self.topic_prefix = topic
-        self.topic = topic + '.' + self.device_id
+        self.topic = self._topic_by_device_id(self.device_id)
         self.producer = None
 
     def _on_record(self, record):
@@ -27,18 +27,15 @@ class KafkaBackend(Backend):
         if not self.producer:
             self.producer = KafkaProducer(bootstrap_servers=self.server)
 
-    def send_msg(self, msg):
-        if isinstance(msg, str):
-            msg = json.loads(msg)
-        if isinstance(msg, dict):
+    def _topic_by_device_id(self, device_id):
+        return '{}.{}'.format(self.topic_prefix, device_id)
+
+    def _send_msg(self, msg):
         target = msg['target']
         msg = json.dumps(msg).encode('utf-8')
-        if not isinstance(msg, bytes):
-            msg = json.dumps(msg)
-            raise RuntimeError('Invalid non-JSON message')
 
         self._init_producer()
-        self.producer.send(self.topic_prefix + '.' + target, msg)
+        self.producer.send(self._topic_by_device_id(target), msg)
         self.producer.flush()
 
     def run(self):

platypush/backend/local/__init__.py

@@ -8,12 +8,9 @@ from .. import Backend
 class LocalBackend(Backend):
     def _init(self, fifo):
         self.fifo = fifo
-    def send_msg(self, msg):
-        if isinstance(msg, dict):
-            msg = json.dumps(msg)
-        if not isinstance(msg, str):
-            raise RuntimeError('Invalid non-JSON message')
 
+    def _send_msg(self, msg):
+        msg = json.dumps(msg)
         msglen = len(msg)+1  # Include \n
         msg = bytearray((str(msglen) + '\n' + msg + '\n').encode('utf-8'))
         with open(self.fifo, 'wb') as f:

platypush/backend/pushbullet/__init__.py

@@ -12,14 +12,6 @@ class PushbulletBackend(Backend):
         self.device_name = device
         self.pb_device_id = self.get_device_id()
 
-    @staticmethod
-    def _on_init(ws):
-        logging.info('Connection opened')
-
-    @staticmethod
-    def _on_close(ws):
-        logging.info('Connection closed')
-
     @staticmethod
     def _on_msg(ws, msg):
         ws.backend._on_push(msg)
@@ -54,7 +46,6 @@ class PushbulletBackend(Backend):
         else:
             return {}
 
-
     def _on_push(self, data):
         try:
             data = json.loads(data) if isinstance(data, str) else push
@@ -82,10 +73,8 @@ class PushbulletBackend(Backend):
     def _init_socket(self):
         self.ws = websocket.WebSocketApp(
             'wss://stream.pushbullet.com/websocket/' + self.token,
-            on_open = self._on_init,
             on_message = self._on_msg,
-            on_error = self._on_error,
-            on_close = self._on_close)
+            on_error = self._on_error)
 
         self.ws.backend = self
 
@@ -104,26 +93,17 @@ class PushbulletBackend(Backend):
 
         return devices[0]['iden']
 
-    def send_msg(self, msg):
-        if isinstance(msg, dict):
-            msg = json.dumps(msg)
-        if not isinstance(msg, str):
-            raise RuntimeError('Invalid non-JSON message')
-
-        response = requests.post(
+    def _send_msg(self, msg):
+        requests.post(
             u'https://api.pushbullet.com/v2/pushes',
             headers = { 'Access-Token': self.token },
             json = {
                 'type': 'note',
                 'device_iden': self.pb_device_id,
-                'body': msg,
+                'body': json.dumps(msg),
             }
         ).json()
 
-        if 'dismissed' not in response or response['dismissed'] is True:
-            raise RuntimeError('Error while pushing the message: {}'.
-                               format(response))
-
     def run(self):
         self._init_socket()
         logging.info('Initialized Pushbullet backend - device_id: {}'