Compute country distance at aggregation time #280

.coveragerc

@@ -6,6 +6,7 @@ include =
 omit = 
     leaderboard/wsgi
     leaderboard/settings*
+    *migrations*
 
 [report]
 # Regexes for lines to exclude from consideration

leaderboard/contributors/migrations/0012_auto_20160428_1827.py

@@ -0,0 +1,39 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+import django.contrib.gis.db.models.fields
+
+
+def set_contribution_point_to_country_center(apps, schema_editor):
+    Contribution = apps.get_model('contributors', 'Contribution')
+    db_alias = schema_editor.connection.alias
+
+    for contribution in Contribution.objects.using(db_alias):
+        contribution.point = contribution.country.geometry.point_on_surface
+        contribution.save()
+
+
+def noop(apps, schema_editor):
+    pass
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('locations', '0006_auto_20160208_2050'),
+        ('contributors', '0011_auto_20160208_2034'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='contribution',
+            name='point',
+            field=django.contrib.gis.db.models.fields.PointField(srid=4326, null=True, blank=True),
+        ),
+        migrations.RunPython(set_contribution_point_to_country_center, noop),
+        migrations.RemoveField(
+            model_name='contribution',
+            name='country',
+        ),
+    ]

leaderboard/contributors/models.py

@@ -1,7 +1,8 @@
 import operator
 
 from bulk_update.helper import bulk_update
-from django.db import models
+from django.conf import settings
+from django.contrib.gis.db import models
 
 from leaderboard.locations.models import Country
 
@@ -66,11 +67,18 @@ def _compute_ranks(cls, contributions):
             (rank.contributor_id, rank.country_id): rank
             for rank in ContributorRank.objects.all()
         }
+        countries = Country.objects.all()
 
         for contribution in contributions:
             # Each contribution counts towards the rank in the country in which
             # it was made, as well as the global rank for that contributor.
-            for country_id in (contribution.country_id, None):
+
+            contribution_country = sorted([
+                (country.geometry.distance(contribution.point), country)
+                for country in countries
+            ])[0][1]
+
+            for country_id in (contribution_country.id, None):
                 rank_key = (contribution.contributor_id, country_id)
                 contributor_rank = contributor_ranks.get(rank_key, None)
 
@@ -146,7 +154,7 @@ class Contribution(models.Model):
     A contribution made by a contributor to the leaderboard.
     """
     date = models.DateField()
-    country = models.ForeignKey(Country)
+    point = models.PointField(srid=settings.WGS84_SRID, blank=True, null=True)
     contributor = models.ForeignKey(Contributor)
     observations = models.PositiveIntegerField(default=0)
 

leaderboard/contributors/serializers.py

@@ -4,7 +4,6 @@
 from django.contrib.gis.geos import Point
 from rest_framework import serializers
 
-from leaderboard.locations.models import Country
 from leaderboard.contributors.models import Contribution
 
 
@@ -20,19 +19,18 @@ class ContributionSerializer(serializers.Serializer):
     observations = serializers.IntegerField()
 
     def create(self, data):
-        date = datetime.datetime.fromtimestamp(data['time']).date()
-
-        country = Country.objects.nearest_to_point(Point(
+        point = Point(
             data['tile_easting_m'],
             data['tile_northing_m'],
             srid=settings.PROJECTION_SRID,
-        ))
+        )
+        point.transform(settings.WGS84_SRID)
 
         Contribution.objects.create(
-            date=date,
-            country=country,
             contributor=self.context['request'].user,
+            date=datetime.datetime.fromtimestamp(data['time']).date(),
             observations=data['observations'],
+            point=point,
         )
 
         return data

leaderboard/contributors/tests/test_models.py

@@ -2,8 +2,10 @@
 import uuid
 
 import factory
-from faker import Factory as FakerFactory
+from django.conf import settings
+from django.contrib.gis.geos import Point
 from django.test import TestCase
+from faker import Factory as FakerFactory
 
 from leaderboard.contributors.models import (
     Contributor,
@@ -28,7 +30,8 @@ class Meta:
 class ContributionFactory(factory.DjangoModelFactory):
     date = factory.LazyAttribute(lambda o: datetime.date.today())
     contributor = factory.SubFactory(ContributorFactory)
-    country = factory.SubFactory(CountryFactory)
+    point = factory.LazyAttribute(
+        lambda o: Point(0, 0, srid=settings.PROJECTION_SRID))
     observations = 1
 
     class Meta:
@@ -42,7 +45,7 @@ def create_contribution(self, contributor, country):
             contributor=contributor,
             date=datetime.date.today(),
             observations=1,
-            country=country,
+            point=country.geometry.centroid,
         )
 
     def setUp(self):

leaderboard/contributors/tests/test_views.py

@@ -28,35 +28,36 @@ def test_submit_multiple_observations(self):
         today = datetime.date.today()
         now = time.mktime(today.timetuple())
         one_day = 24 * 60 * 60
+        point = Point(-8872100, 5435700, srid=settings.PROJECTION_SRID)
 
         observation_data = {
             'items': [
                 # A contribution for tile1 at time1
                 {
                     'time': now,
-                    'tile_easting_m': -8872100,
-                    'tile_northing_m': 5435700,
+                    'tile_easting_m': point.coords[0],
+                    'tile_northing_m': point.coords[1],
                     'observations': 100,
                 },
                 # A contribution for tile1 at time 1
                 {
                     'time': now,
-                    'tile_easting_m': -8872100,
-                    'tile_northing_m': 5435700,
+                    'tile_easting_m': point.coords[0],
+                    'tile_northing_m': point.coords[1],
                     'observations': 100,
                 },
                 # A contribution for tile2 at time1
                 {
                     'time': now,
-                    'tile_easting_m': -8892100,
-                    'tile_northing_m': 5435700,
+                    'tile_easting_m': point.coords[0],
+                    'tile_northing_m': point.coords[1],
                     'observations': 100,
                 },
                 # A contribution for tile2 at time2
                 {
                     'time': now + one_day,
-                    'tile_easting_m': -8892100,
-                    'tile_northing_m': 5435700,
+                    'tile_easting_m': point.coords[0],
+                    'tile_northing_m': point.coords[1],
                     'observations': 100,
                 },
             ],
@@ -75,16 +76,18 @@ def test_submit_multiple_observations(self):
 
         self.assertEqual(Contribution.objects.count(), 4)
 
+        point.transform(settings.WGS84_SRID)
+
         self.assertEqual(Contribution.objects.filter(date=today).count(), 3)
         for contribution in Contribution.objects.filter(date=today):
             self.assertEqual(contribution.contributor, self.contributor)
-            self.assertEqual(contribution.country, self.country)
+            self.assertEqual(contribution.point, point)
             self.assertEqual(contribution.observations, 100)
 
         contribution = Contribution.objects.get(
             date=(today + datetime.timedelta(days=1)))
         self.assertEqual(contribution.contributor, self.contributor)
-        self.assertEqual(contribution.country, self.country)
+        self.assertEqual(contribution.point, point)
         self.assertEqual(contribution.observations, 100)
 
     def test_position_converted_to_lat_lon(self):
@@ -142,8 +145,10 @@ def test_position_converted_to_lat_lon(self):
 
         self.assertEqual(response.status_code, 201)
 
+        sample_point.transform(settings.WGS84_SRID)
+
         contribution = Contribution.objects.get()
-        self.assertEqual(contribution.country, country1)
+        self.assertEqual(contribution.point, sample_point)
 
     def test_missing_authentication_token_returns_401(self):
         response = self.client.post(

leaderboard/leaders/tests/test_views.py

@@ -29,7 +29,7 @@ def test_get_leader_profile_returns_ranks_and_observations(self):
                     contributor=contributor,
                     date=today,
                     observations=1,
-                    country=country,
+                    point=country.geometry.centroid,
                 )
 
         # Create the contributor ranks
@@ -95,7 +95,7 @@ def test_sums_for_each_contributor_and_orders_by_observations(self):
                 contributor=contributor1,
                 date=today,
                 observations=1,
-                country=country1,
+                point=country1.geometry.centroid,
             ).save()
 
         contributor2 = ContributorFactory()
@@ -105,7 +105,7 @@ def test_sums_for_each_contributor_and_orders_by_observations(self):
                 contributor=contributor2,
                 date=today,
                 observations=1,
-                country=country2,
+                point=country2.geometry.centroid,
             ).save()
 
         # Create a contributor with no contributions
@@ -149,7 +149,7 @@ def test_leaderboard_is_paginated(self):
                 contributor=contributor,
                 date=today,
                 observations=1,
-                country=country,
+                point=country.geometry.centroid,
             ).save()
 
         # Create the contributor ranks
@@ -181,7 +181,7 @@ def test_leader_with_no_name_not_shown(self):
                 contributor=contributor1,
                 date=today,
                 observations=1,
-                country=country,
+                point=country.geometry.centroid,
             ).save()
 
         contributor2 = ContributorFactory(name='')
@@ -191,7 +191,7 @@ def test_leader_with_no_name_not_shown(self):
                 contributor=contributor2,
                 date=today,
                 observations=1,
-                country=country,
+                point=country.geometry.centroid,
             ).save()
 
         # Create a contributor with no contributions
@@ -232,23 +232,23 @@ def test_filters_by_country(self):
             contributor=contributor,
             date=today,
             observations=1,
-            country=country1,
+            point=country1.geometry.centroid,
         )
         contribution1.save()
 
         contribution2 = Contribution(
             contributor=contributor,
             date=today,
             observations=1,
-            country=country1,
+            point=country1.geometry.centroid,
         )
         contribution2.save()
 
         contribution3 = Contribution(
             contributor=contributor,
             date=today,
             observations=1,
-            country=country2,
+            point=country2.geometry.centroid,
         )
         contribution3.save()
 

leaderboard/locations/models.py

@@ -15,22 +15,6 @@ def annotate_observations(self):
         ).filter(observations__gt=0)
 
 
-class CountryManager(models.GeoManager):
-    """
-    A model manager for Countries which allows you to
-    query countries which are closest to a point.
-    """
-
-    def get_queryset(self):
-        return CountryQuerySet(self.model, using=self._db)
-
-    def nearest_to_point(self, point):
-        country = self.get_queryset().distance(point).order_by('distance')[:1]
-
-        if country.exists():
-            return country.get()
-
-
 class Country(models.Model):
     """
     A country as defined by:
@@ -49,7 +33,7 @@ class Country(models.Model):
     subregion = models.IntegerField('Sub-Region Code')
     geometry = models.MultiPolygonField(srid=settings.WGS84_SRID)
 
-    objects = CountryManager()
+    objects = CountryQuerySet.as_manager()
 
     class Meta:
         ordering = ('name',)

leaderboard/locations/tests/test_models.py

@@ -2,7 +2,6 @@
 
 import factory
 from django.contrib.gis.geos import Point, Polygon, MultiPolygon
-from django.test import TestCase
 
 from leaderboard.locations.models import Country
 
@@ -29,26 +28,3 @@ class CountryFactory(factory.DjangoModelFactory):
 
     class Meta:
         model = Country
-
-
-class TestCountryManager(TestCase):
-
-    def test_nearest_to_point_returns_nearest_country(self):
-        country1 = CountryFactory.build()
-        country1.save()
-
-        country2 = CountryFactory.build()
-        country2.geometry = MultiPolygon([
-            Polygon([
-                Point(1000, 1000),
-                Point(1000, 1001),
-                Point(1001, 1000),
-                Point(1001, 1001),
-                Point(1000, 1000),
-            ]),
-        ])
-        country2.save()
-
-        point = Point(0, 0)
-        nearest_country = Country.objects.nearest_to_point(point)
-        self.assertEqual(nearest_country, country1)

leaderboard/locations/tests/test_views.py

@@ -27,7 +27,7 @@ def test_list_countries_returns_country_data(self):
                 for contribution_i in range(10):
                     Contribution.objects.create(
                         contributor=contributor,
-                        country=country,
+                        point=country.geometry.centroid,
                         date=today,
                         observations=1,
                     )