use client id to avoid self-flocking

model.py

@@ -2,7 +2,7 @@
 Object-Document Map for bike model
 """
 from mongoengine import Document, DateTimeField, GeoPointField, \
-    FloatField, connection
+    FloatField, StringField, connection
 import bson
 import datetime
 from LatLon23 import LatLon, Latitude, Longitude
@@ -54,6 +54,7 @@ class Bike(Document):
     speed = FloatField(default=0)
     bearing = FloatField(default=0)
     last_update = DateTimeField(default=datetime.datetime.utcnow)
+    client_id = StringField(required=True)
 
     def __init__(self, *args, **kwargs):
         super(Document, self).__init__(*args, **kwargs)
@@ -105,7 +106,7 @@ class Bike(Document):
                 min_age = min_step / self.speed
             else:
                 min_age = 60
-        
+
         trip_len = distance.geodesic(self.get_point(), self.get_dest()).meters
 
         local_radius = trip_len * point_altruism
@@ -121,7 +122,9 @@ class Bike(Document):
                                  'coordinates': self.point},
                              '$maxDistance': local_radius}},
                       'last_update': {
-                          '$gte': datetime.datetime.now() - datetime.timedelta(seconds=min_age)},
+                          '$gte': (datetime.datetime.now()
+                                   - datetime.timedelta(seconds=min_age))},
+                      'client_id': {'$ne': self.client_id},
                       '_id': {'$ne': bson.objectid.ObjectId(self.id)}})]
 
         local_ids = set([bike['_id'] for bike in local])
@@ -134,14 +137,18 @@ class Bike(Document):
                             {'$geometry': {'type': 'Point',
                                            'coordinates': self.destination},
                              '$maxDistance': destination_radius}},
+                       'client_id': {'$ne': self.client_id},
+                       '_id': {'$ne': bson.objectid.ObjectId(self.id)},
                        'last_update': {
-                           '$gte': datetime.datetime.now() - datetime.timedelta(seconds=min_age)}
-                      })]
+                           '$gte': (datetime.datetime.now()
+                                    - datetime.timedelta(seconds=min_age))}
+                       })]
         remote_ids = set([bike['_id'] for bike in remote])
 
         # intersect them!
         flock_ids = local_ids.intersection(remote_ids)
 
+        # return bikes, not bike ids
         return (bike for bike in local if bike['_id'] in flock_ids)
 
     def flock_data(self):

server.py

@@ -11,15 +11,17 @@ db = MongoEngine(app)
 # TODO: at registration give current location
 @app.route("/register/")
 def register():
-    dest_lat = request.args.get('dest_lat', None)
     dest_lon = request.args.get('dest_lon', None)
+    dest_lat = request.args.get('dest_lat', None)
+    client_id = request.args.get('client_id', None)
 
-    assert dest_lat is not None and dest_lon is not None
+    assert dest_lat is not None and dest_lon is not None and client_id is not None
 
     dest = (float(dest_lon), float(dest_lat))
 
     bike = Bike(point=(0, 0),
-                destination=dest)
+                destination=dest,
+                client_id=client_id)
 
     bike.save()
 
@@ -36,12 +38,13 @@ def update(bike_id):
     lon = float(request.args.get('lon', None))
     speed = float(request.args.get('speed', None))
     bearing = float(request.args.get('bearing', None))
+    client_id = request.args.get('client_id', None)
 
-    local_altruism = float(request.args.get('local_altruism', 0.1))
-    dest_altruism = float(request.args.get('dest_altruism', 0.2))
+    # TODO: maybe client tunes these?
+    # local_altruism = float(request.args.get('local_altruism', 0.1))
+    # dest_altruism = float(request.args.get('dest_altruism', 0.2))
 
-    
-    bike.update(lat, lon, speed, bearing)
+    bike.update(lat, lon, speed, bearing, client_id)
 
     return jsonify(last_update=bike.last_update.isoformat(),
                    **bike.flock_data())