Added Foursquare backend

docs/source/backends.rst

@@ -15,6 +15,7 @@ Backends
     platypush/backend/button.flic.rst
     platypush/backend/camera.pi.rst
     platypush/backend/chat.telegram.rst
+    platypush/backend/foursquare.rst
     platypush/backend/google.fit.rst
     platypush/backend/google.pubsub.rst
     platypush/backend/gps.rst

docs/source/events.rst

@@ -15,6 +15,7 @@ Events
     platypush/events/camera.rst
     platypush/events/chat.telegram.rst
     platypush/events/distance.rst
+    platypush/events/foursquare.rst
     platypush/events/geo.rst
     platypush/events/google.rst
     platypush/events/google.fit.rst

docs/source/platypush/backend/foursquare.rst

@@ -0,0 +1,5 @@
+``platypush.backend.foursquare``
+================================
+
+.. automodule:: platypush.backend.foursquare
+    :members:

docs/source/platypush/events/foursquare.rst

@@ -0,0 +1,5 @@
+``platypush.message.event.foursquare``
+======================================
+
+.. automodule:: platypush.message.event.foursquare
+    :members:

platypush/backend/foursquare.py

@@ -0,0 +1,55 @@
+import time
+
+from platypush.backend import Backend
+from platypush.context import get_plugin
+from platypush.message.event.foursquare import FoursquareCheckinEvent
+
+
+class FoursquareBackend(Backend):
+    """
+    This backend polls for new check-ins on the user's Foursquare account and triggers an event when a new check-in
+    occurs.
+
+    Requires:
+
+        * The :class:`platypush.plugins.foursquare.FoursquarePlugin` plugin configured and enabled.
+
+    Triggers:
+
+        - :class:`platypush.message.event.foursquare.FoursquareCheckinEvent` when a new check-in occurs.
+
+    """
+
+    _last_created_at_varname = '_foursquare_checkin_last_created_at'
+
+    def __init__(self, poll_seconds: float = 60.0, *args, **kwargs):
+        """
+        :param poll_seconds: How often the backend should check for new check-ins (default: one minute).
+        """
+        super().__init__(*args, **kwargs)
+        self.poll_seconds = poll_seconds
+        self._last_created_at = None
+
+    def run(self):
+        super().run()
+        self._last_created_at = int(get_plugin('variable').get(self._last_created_at_varname).
+                                    output.get(self._last_created_at_varname))
+        self.logger.info('Started Foursquare backend')
+
+        while not self.should_stop():
+            try:
+                checkins = get_plugin('foursquare').get_checkins().output
+                if checkins:
+                    last_checkin = checkins[0]
+                    if not self._last_created_at or last_checkin.get('createdAt', 0) > self._last_created_at:
+                        self.bus.post(FoursquareCheckinEvent(checkin=last_checkin))
+                        self._last_created_at = last_checkin.get('createdAt', 0)
+                        get_plugin('variable').set(**{self._last_created_at_varname: self._last_created_at})
+            except Exception as e:
+                self.logger.error('Error while retrieving the list of checkins: {}'.format(str(e)))
+                self.logger.exception(e)
+            finally:
+                time.sleep(self.poll_seconds)
+
+
+# vim:sw=4:ts=4:et:

platypush/message/event/foursquare.py

@@ -0,0 +1,14 @@
+from typing import Dict, Any
+
+from platypush.message.event import Event
+
+
+class FoursquareCheckinEvent(Event):
+    """
+    Event triggered when a new check-in occurs.
+    """
+    def __init__(self, checkin: Dict[str, Any], *args, **kwargs):
+        super().__init__(*args, checkin=checkin, **kwargs)
+
+
+# vim:sw=4:ts=4:et: