Add GPS accuracy check for a location update or an event update

Add tests related to this
Great thanks to @pavoni for his support on this fix

homeassistant/components/device_tracker/owntracks.py

@@ -28,10 +28,14 @@ _LOGGER = logging.getLogger(__name__)
 
 LOCK = threading.Lock()
 
+CONF_MAX_GPS_ACCURACY = 'max_gps_accuracy'
+
 
 def setup_scanner(hass, config, see):
     """ Set up an OwnTracks tracker. """
 
+    max_gps_accuracy = config.get(CONF_MAX_GPS_ACCURACY)
+
     def owntracks_location_update(topic, payload, qos):
         """ MQTT message received. """
 
@@ -45,7 +49,9 @@ def setup_scanner(hass, config, see):
                 'Unable to parse payload as JSON: %s', payload)
             return
 
-        if not isinstance(data, dict) or data.get('_type') != 'location':
+        if (not isinstance(data, dict) or data.get('_type') != 'location') or (
+                'acc' in data and max_gps_accuracy is not None and data[
+                    'acc'] > max_gps_accuracy):
             return
 
         dev_id, kwargs = _parse_see_args(topic, data)
@@ -124,12 +130,20 @@ def setup_scanner(hass, config, see):
                         kwargs['location_name'] = new_region
                     _set_gps_from_zone(kwargs, zone)
                     _LOGGER.info("Exit to %s", new_region)
+                    see(**kwargs)
+                    see_beacons(dev_id, kwargs)
 
                 else:
                     _LOGGER.info("Exit to GPS")
+                    # Check for GPS accuracy
+                    if not ('acc' in data and
+                            max_gps_accuracy is not None and
+                            data['acc'] > max_gps_accuracy):
 
-                see(**kwargs)
+                        see(**kwargs)
-                see_beacons(dev_id, kwargs)
+                        see_beacons(dev_id, kwargs)
+                    else:
+                        _LOGGER.info("Inaccurate GPS reported")
 
                 beacons = MOBILE_BEACONS_ACTIVE[dev_id]
                 if location in beacons:

tests/components/device_tracker/test_owntracks.py

@@ -30,6 +30,8 @@ DEVICE_TRACKER_STATE = "device_tracker.{}_{}".format(USER, DEVICE)
 IBEACON_DEVICE = 'keys'
 REGION_TRACKER_STATE = "device_tracker.beacon_{}".format(IBEACON_DEVICE)
 
+CONF_MAX_GPS_ACCURACY = 'max_gps_accuracy'
+
 LOCATION_MESSAGE = {
     'batt': 92,
     'cog': 248,
@@ -45,6 +47,21 @@ LOCATION_MESSAGE = {
     'tst': 1,
     'vel': 0}
 
+LOCATION_MESSAGE_INACCURATE = {
+    'batt': 92,
+    'cog': 248,
+    'tid': 'user',
+    'lon': 2.0,
+    't': 'u',
+    'alt': 27,
+    'acc': 2000,
+    'p': 101.3977584838867,
+    'vac': 4,
+    'lat': 6.0,
+    '_type': 'location',
+    'tst': 1,
+    'vel': 0}
+
 REGION_ENTER_MESSAGE = {
     'lon': 1.0,
     'event': 'enter',
@@ -70,6 +87,18 @@ REGION_LEAVE_MESSAGE = {
     'lat': 2.0,
     '_type': 'transition'}
 
+REGION_LEAVE_INACCURATE_MESSAGE = {
+    'lon': 10.0,
+    'event': 'leave',
+    'tid': 'user',
+    'desc': 'inner',
+    'wtst': 1,
+    't': 'b',
+    'acc': 2000,
+    'tst': 2,
+    'lat': 20.0,
+    '_type': 'transition'}
+
 
 class TestDeviceTrackerOwnTracks(unittest.TestCase):
     """ Test the Template sensor. """
@@ -80,7 +109,8 @@ class TestDeviceTrackerOwnTracks(unittest.TestCase):
         mock_mqtt_component(self.hass)
         self.assertTrue(device_tracker.setup(self.hass, {
             device_tracker.DOMAIN: {
-                CONF_PLATFORM: 'owntracks'
+                CONF_PLATFORM: 'owntracks',
+                CONF_MAX_GPS_ACCURACY: 200
             }}))
 
         self.hass.states.set(
@@ -146,6 +176,10 @@ class TestDeviceTrackerOwnTracks(unittest.TestCase):
         state = self.hass.states.get(DEVICE_TRACKER_STATE)
         self.assertEqual(state.attributes.get('latitude'), latitude)
 
+    def assert_location_longitude(self, longitude):
+        state = self.hass.states.get(DEVICE_TRACKER_STATE)
+        self.assertEqual(state.attributes.get('longitude'), longitude)
+
     def assert_location_accuracy(self, accuracy):
         state = self.hass.states.get(DEVICE_TRACKER_STATE)
         self.assertEqual(state.attributes.get('gps_accuracy'), accuracy)
@@ -169,6 +203,13 @@ class TestDeviceTrackerOwnTracks(unittest.TestCase):
         self.assert_location_accuracy(60.0)
         self.assert_location_state('outer')
 
+    def test_location_inaccurate_gps(self):
+        self.send_message(LOCATION_TOPIC, LOCATION_MESSAGE)
+        self.send_message(LOCATION_TOPIC, LOCATION_MESSAGE_INACCURATE)
+
+        self.assert_location_latitude(2.0)
+        self.assert_location_longitude(1.0)
+
     def test_event_entry_exit(self):
         self.send_message(EVENT_TOPIC, REGION_ENTER_MESSAGE)
 
@@ -194,6 +235,24 @@ class TestDeviceTrackerOwnTracks(unittest.TestCase):
         # Left clean zone state
         self.assertFalse(owntracks.REGIONS_ENTERED[USER])
 
+    def test_event_entry_exit_inaccurate(self):
+        self.send_message(EVENT_TOPIC, REGION_ENTER_MESSAGE)
+
+        # Enter uses the zone's gps co-ords
+        self.assert_location_latitude(2.1)
+        self.assert_location_accuracy(10.0)
+        self.assert_location_state('inner')
+
+        self.send_message(EVENT_TOPIC, REGION_LEAVE_INACCURATE_MESSAGE)
+
+        # Exit doesn't use inaccurate gps
+        self.assert_location_latitude(2.1)
+        self.assert_location_accuracy(10.0)
+        self.assert_location_state('inner')
+
+        # But does exit region correctly
+        self.assertFalse(owntracks.REGIONS_ENTERED[USER])
+
     def test_event_exit_outside_zone_sets_away(self):
         self.send_message(EVENT_TOPIC, REGION_ENTER_MESSAGE)
         self.assert_location_state('inner')