Add max_generation parameter.

CHANGES.txt

@@ -1,4 +1,6 @@
 Unreleased
+    * New features:
+        * Add max_generation parameter to all locations min_generation can be used.
     * Development improvements:
         * Add support for filtering / excluding areas by multiple types or countries in raise generation script.
 

mapit/models.py

@@ -6,6 +6,7 @@
 from django.contrib.gis.db import models
 from django.conf import settings
 from django.db import connection
+from django.db.models import Q
 from django.db.models.query import RawQuerySet
 from django.utils.encoding import smart_str
 from django.utils.functional import cached_property
@@ -47,21 +48,26 @@ def new(self):
         return latest[0]
 
     def query_args(self, request, format):
-        try:
-            generation = int(request.GET.get('generation', 0))
-        except ValueError:
-            raise ViewException(format, _('Bad generation specified'), 400)
-        if not generation:
-            generation = self.current().id
-
-        try:
-            min_generation = int(request.GET.get('min_generation', 0))
-        except ValueError:
-            raise ViewException(format, _('Bad min_generation specified'), 400)
-        if not min_generation:
-            min_generation = generation
+        args = {}
+        for q in ('generation', 'min_generation', 'max_generation'):
+            try:
+                args[q] = int(request.GET.get(q, 0))
+            except ValueError:
+                raise ViewException(format, _('Bad value specified for %s parameter') % q, 400)
+        if not args['generation']:
+            args['generation'] = self.current().id
+
+        q = {
+            'generation_low__lte': args['generation']
+        }
+        if args['max_generation']:
+            q['generation_high__lte'] = args['max_generation']
+        if args['min_generation']:
+            q['generation_high__gte'] = args['min_generation']
+        if not args['max_generation'] and not args['min_generation']:
+            q['generation_high__gte'] = args['generation']
 
-        return generation, min_generation
+        return Q(**q)
 
 
 class Generation(models.Model):
@@ -157,28 +163,16 @@ def get_queryset(self):
         return super(AreaManager, self).get_queryset().select_related(
             'type', 'country', 'parent_area').prefetch_related('countries')
 
-    def by_location(self, location, generation=None, min_generation=None):
-        if generation is None:
-            generation = Generation.objects.current()
-        if min_generation is None:
-            min_generation = Generation.objects.current()
+    def by_location(self, location, query):
         if not location:
             return []
-        return Area.objects.filter(
-            polygons__subdivided__division__contains=location,
-            generation_low__lte=generation, generation_high__gte=min_generation
-        )
+        query &= Q(polygons__subdivided__division__contains=location)
+        return Area.objects.filter(query)
 
-    def by_postcode(self, postcode, generation=None, min_generation=None):
-        if generation is None:
-            generation = Generation.objects.current()
-        if min_generation is None:
-            min_generation = Generation.objects.current()
+    def by_postcode(self, postcode, query):
         return list(itertools.chain(
-            self.by_location(postcode.location, generation, min_generation),
-            postcode.areas.filter(
-                generation_low__lte=generation, generation_high__gte=min_generation
-            )
+            self.by_location(postcode.location, query),
+            postcode.areas.filter(query)
         ))
 
     # In order for this query to be performant, we have to do it ourselves.

mapit/templates/mapit/api/area.html

@@ -67,6 +67,9 @@ <h3>{% blocktrans trimmed %}<em>lookup</em> related areas {% endblocktrans %}</h
                     {% blocktrans trimmed %}
                         <li><i>min_generation</i>, to return areas since that generation (children only).</li>
                     {% endblocktrans %}
+                    {% blocktrans trimmed %}
+                        <li><i>max_generation</i>, to return results up to that generation, not active after (children only).</li>
+                    {% endblocktrans %}
                 </ul></dd>
                 <dt>{% trans "Returns" %}:</dt>
                 <dd>{% trans "A hash of areas that match the requested lookup." %}

mapit/templates/mapit/api/areas.html

@@ -23,6 +23,7 @@ <h3>{% blocktrans trimmed %}
             <dd><ul>
                 <li><i>generation</i>, {% trans "to return areas in that generation (type and name lookups only)" %}.</li>
                 <li><i>min_generation</i>, {% trans "to return areas since that generation (type and name lookups only)" %}.</li>
+                <li><i>max_generation</i>, {% trans "to return results up to that generation, not active after (ditto)." %}.</li>
                 <li><i>type</i>, {% trans "to restrict results to a type or types (multiple separated by commas; name lookup only)" %}.</li>
                 <li><i>country</i>, {% trans "to restrict results to areas with particular country codes (multiple separated by commas; type and name lookups only)" %}.</li>
             </ul></dd>

mapit/templates/mapit/api/point.html

@@ -58,6 +58,11 @@ <h3>{% blocktrans trimmed %}
                                 <i>min_generation</i>, to return results since that generation.
                             {% endblocktrans %}
                         </li>
+                        <li>
+                            {% blocktrans trimmed %}
+                                <i>max_generation</i>, to return results up to that generation, not active after.
+                            {% endblocktrans %}
+                        </li>
                         <li>
                             {% blocktrans trimmed %}
                                 <i>country</i>, to restrict results to areas with particular country codes (multiple country codes separated by commas).

mapit/templates/mapit/api/postcode.html

@@ -27,6 +27,10 @@ <h3>
             {% blocktrans trimmed %}
                 <i>min_generation</i>, to return results since that generation.
             {% endblocktrans %}
+            </li><li>
+            {% blocktrans trimmed %}
+                <i>max_generation</i>, to return results up to that generation, not active after.
+            {% endblocktrans %}
         </li></ul></dd>
 
         {% include "mapit/api/postcode-example.html" %}

mapit/tests/test_query_args.py

@@ -23,6 +23,10 @@ def __init__(self, params):
 class QueryArgsTest(TestCase):
 
     def setUp(self):
+        self.older_generation = Generation.objects.create(
+            active=False,
+            description="Older test generation",
+        )
         self.old_generation = Generation.objects.create(
             active=False,
             description="Old test generation",
@@ -32,12 +36,9 @@ def setUp(self):
             description="Test generation",
         )
 
-    def q_equality(self, act, exp):
-        self.assertEqual(str(act), str(exp))
-
     def test_no_type(self):
         q = query_args(FakeRequest({}), 'json', None)
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.active_generation.id,
@@ -47,7 +48,7 @@ def test_no_type(self):
 
     def test_one_type_in_query(self):
         q = query_args(FakeRequest({'type': 'WMC'}), 'json', None)
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.active_generation.id,
@@ -57,7 +58,7 @@ def test_one_type_in_query(self):
 
     def test_two_types_in_query(self):
         q = query_args(FakeRequest({'type': 'WMC,EUR'}), 'json', None)
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.active_generation.id,
@@ -67,7 +68,7 @@ def test_two_types_in_query(self):
 
     def test_one_type_in_params(self):
         q = query_args(FakeRequest({}), 'json', 'WMC')
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.active_generation.id,
@@ -77,7 +78,7 @@ def test_one_type_in_params(self):
 
     def test_two_types_in_params(self):
         q = query_args(FakeRequest({}), 'json', 'WMC,EUR')
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.active_generation.id,
@@ -90,7 +91,7 @@ def test_generation_specified(self):
             FakeRequest({'generation': self.old_generation.id}),
             'json',
             None)
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.old_generation.id,
@@ -103,7 +104,7 @@ def test_min_generation_specified(self):
             FakeRequest({'min_generation': self.old_generation.id}),
             'json',
             None)
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.old_generation.id,
@@ -113,7 +114,7 @@ def test_min_generation_specified(self):
 
     def test_one_country_in_query(self):
         q = query_args(FakeRequest({'country': 'DE'}), 'json', None)
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.active_generation.id,
@@ -123,7 +124,7 @@ def test_one_country_in_query(self):
 
     def test_two_countries_in_query(self):
         q = query_args(FakeRequest({'country': 'DE,FR'}), 'json', None)
-        self.q_equality(
+        self.assertEqual(
             q,
             Q(
                 generation_high__gte=self.active_generation.id,
@@ -132,14 +133,49 @@ def test_two_countries_in_query(self):
         )
 
     def test_generation_manager_query_args(self):
-        gen, min_gen = Generation.objects.query_args(
+        q = Generation.objects.query_args(
             FakeRequest({'generation': self.old_generation.id}),
             'json')
-        self.assertEqual(gen, self.old_generation.id)
-        self.assertEqual(min_gen, self.old_generation.id)
+        self.assertEqual(
+            q,
+            Q(
+                generation_high__gte=self.old_generation.id,
+                generation_low__lte=self.old_generation.id,
+            )
+        )
 
-        gen, min_gen = Generation.objects.query_args(
+        q = Generation.objects.query_args(
             FakeRequest({'min_generation': self.old_generation.id}),
             'json')
-        self.assertEqual(min_gen, self.old_generation.id)
-        self.assertEqual(gen, self.active_generation.id)
+        self.assertEqual(
+            q,
+            Q(
+                generation_high__gte=self.old_generation.id,
+                generation_low__lte=self.active_generation.id,
+            )
+        )
+
+        q = Generation.objects.query_args(
+            FakeRequest({'max_generation': self.old_generation.id}),
+            'json')
+        self.assertEqual(
+            q,
+            Q(
+                generation_high__lte=self.old_generation.id,
+                generation_low__lte=self.active_generation.id,
+            )
+        )
+
+        q = Generation.objects.query_args(
+            FakeRequest({
+                'max_generation': self.old_generation.id, 'min_generation': self.older_generation.id
+            }),
+            'json')
+        self.assertEqual(
+            q,
+            Q(
+                generation_high__gte=self.older_generation.id,
+                generation_high__lte=self.old_generation.id,
+                generation_low__lte=self.active_generation.id,
+            )
+        )

mapit/views/areas.py

@@ -60,21 +60,12 @@ def output_areas(request, title, format, areas, **kwargs):
 
 
 def query_args(request, format, type=None):
-    generation, min_generation = Generation.objects.query_args(request, format)
+    query = Generation.objects.query_args(request, format)
 
     if type is None:
         type = request.GET.get('type', '')
     country_code = request.GET.get('country', '')
 
-    args = {}
-    if min_generation > -1:
-        args = {
-            'generation_low__lte': generation,
-            'generation_high__gte': min_generation,
-        }
-
-    query = Q(**args)
-
     for attr, value in [
             (['type'], type),
             (['country', 'countries'], country_code),

mapit/views/postcodes.py

@@ -68,10 +68,10 @@ def postcode(request, postcode, format=None):
         raise ViewException(format, "Postcode '%s' is not valid." % postcode, 400)
     postcode = get_object_or_404(Postcode, format=format, postcode=postcode)
 
-    generation, min_generation = Generation.objects.query_args(request, format)
+    query = Generation.objects.query_args(request, format)
 
     if not hasattr(countries, 'is_special_postcode') or not countries.is_special_postcode(postcode.postcode):
-        areas = list(add_codes(Area.objects.by_postcode(postcode, generation, min_generation)))
+        areas = list(add_codes(Area.objects.by_postcode(postcode, query)))
     else:
         areas = []