More robust reconnection logic for Pushbullet backend

platypush/backend/pushbullet/__init__.py

@@ -43,6 +43,7 @@ class PushbulletBackend(Backend):
         self.pb_device_id = None
         self.pb = None
         self.listener = None
+        self._retrying = False
 
     def _initialize(self):
         # noinspection PyPackageRequirements
@@ -132,16 +133,32 @@ class PushbulletBackend(Backend):
         self.close()
         self.logger.info('Pushbullet backend terminated')
 
-    def on_error(self, e):
-        self.logger.exception(e)
+    def on_error(self, err=None):
+        if err:
+            self.logger.exception(err)
+            try:
                 self.close()
+            except Exception as e:
+                self.logger.warning(f'close() error: {e}')
+
+        if not self._retrying:
+            time.sleep(5)
+            self.logger.info('Retrying connection')
+            self._retrying = True
             self.run_listener()
 
+    def on_open(self):
+        self.logger.info('Pushbullet service connected')
+        self._retrying = False
+
     def run_listener(self):
-        from pushbullet import Listener
+        from .listener import Listener
 
         self.logger.info('Initializing Pushbullet backend - device_id: {}'.format(self.device_name))
-        self.listener = Listener(account=self.pb, on_push=self.on_push(), on_error=self.on_error,
+        self.listener = Listener(account=self.pb, on_push=self.on_push(),
+                                 on_open=self.on_open,
+                                 on_close=self.on_error,
+                                 on_error=self.on_error,
                                  http_proxy_host=self.proxy_host,
                                  http_proxy_port=self.proxy_port)
 

platypush/backend/pushbullet/listener.py

@@ -0,0 +1,37 @@
+from typing import Callable, Optional
+
+from pushbullet import Listener as _Listener
+
+
+class Listener(_Listener):
+    """
+    Extends the Pushbullet Listener object by adding ``on_open`` and ``on_close`` handlers.
+    """
+    def __init__(self,
+                 *args,
+                 on_open: Optional[Callable[[], None]] = None,
+                 on_close: Optional[Callable[[], None]] = None,
+                 **kwargs):
+        super().__init__(*args, **kwargs)
+        self._on_open_hndl = on_open
+        self._on_close_hndl = on_close
+
+    def _on_open(self):
+        def callback(*_):
+            self.connected = True
+            self.last_update = time.time()
+            if self._on_open_hndl:
+                self._on_open_hndl()
+
+        return callback
+
+    def _on_close(self):
+        def callback(*_):
+            self.connected = False
+            if self._on_close_hndl:
+                self._on_close_hndl()
+
+        return callback
+
+
+# vim:sw=4:ts=4:et: