Allow to filter changesets by osm tags with OR condition (#627)

* Allow to filter changesets by osm tags with OR condition

* Fix tests

* Another test fix

osmchadjango/changeset/filters.py

@@ -269,6 +269,14 @@ class ChangesetFilter(GeoFilterSet):
             values. To query by any value use key=*.
         """
         )
+    all_tag_changes = filters.CharFilter(
+        field_name='tag_changes',
+        method='filter_all_tag_changes',
+        help_text="""Filter changesets by the tag_changes field using the AND logic. It supports a
+            combination of OSM tags and will query using both the old and new
+            values. To query by any value use key=*.
+        """
+        )
 
     def get_past_n_days(self, queryset, field_name, value):
         start_date = date.today() - timedelta(days=int(value))
@@ -281,7 +289,7 @@ def split_values(self, value):
             if len(t.split('=')) == 2
             ]
 
-    def filter_tag_changes(self, queryset, name, value):
+    def filter_all_tag_changes(self, queryset, name, value):
         for query in self.split_values(value):
             if query[1] == '*':
                 key = 'tag_changes__has_key'
@@ -292,6 +300,21 @@ def filter_tag_changes(self, queryset, name, value):
                 queryset = queryset.filter(**{key: query[1]})
         return queryset
 
+    def filter_tag_changes(self, queryset, name, value):
+        or_condition = Q()
+        keys = []
+        for query in self.split_values(value):
+            if query[1] == '*':
+                keys.append(query[0])
+            else:
+                key = 'tag_changes__{}__contains'.format(query[0])
+                or_condition.add(Q(**{key: query[1]}), Q.OR)
+        if len(keys):
+            or_condition.add(Q(**{'tag_changes__has_any_keys': keys}), Q.OR)
+
+        queryset = queryset.filter(or_condition)
+        return queryset
+
     def filter_metadata(self, queryset, name, value):
         for query in self.split_values(value):
             if '__' in query[0]:

osmchadjango/changeset/tests/test_filters.py

@@ -399,17 +399,34 @@ def test_metadata_filter(self):
         self.assertEqual(ChangesetFilter({'metadata': 'wrongtag__min=abc'}).qs.count(), 0)
         self.assertEqual(ChangesetFilter({'metadata': 'closed:improveosm=*'}).qs.count(), 1)
 
+    def test_all_tag_changes_filter(self):
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'amenity=*'}).qs.count(), 1)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'highway=*'}).qs.count(), 2)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'surface=grass'}).qs.count(), 1)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'highway=primary'}).qs.count(), 1)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'highway=tertiary'}).qs.count(), 2)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'highway=tertiary_link'}).qs.count(), 1)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'highway=tertiary,name=*'}).qs.count(), 1)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'highway=tertiary_link,surface=*'}).qs.count(), 1)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'highway=tertiary_link,name=Sky'}).qs.count(), 0)
+        self.assertEqual(ChangesetFilter({'all_tag_changes': 'highway=tertiary_link,highway=primary'}).qs.count(), 0)
+
     def test_tag_changes_filter(self):
-        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=*'}).qs.count(), 2)
+        # with one tag, the result is the same as all_tag_changes
         self.assertEqual(ChangesetFilter({'tag_changes': 'amenity=*'}).qs.count(), 1)
+        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=*'}).qs.count(), 2)
         self.assertEqual(ChangesetFilter({'tag_changes': 'surface=grass'}).qs.count(), 1)
         self.assertEqual(ChangesetFilter({'tag_changes': 'highway=primary'}).qs.count(), 1)
         self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary'}).qs.count(), 2)
         self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary_link'}).qs.count(), 1)
-        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary,name=*'}).qs.count(), 1)
-        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary_link,surface=*'}).qs.count(), 1)
-        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary_link,name=Sky'}).qs.count(), 0)
-        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary_link,highway=primary'}).qs.count(), 0)
+        # with multiple tags, it filters using the OR condition
+        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary_link,highway=primary'}).qs.count(), 2)
+        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary,surface=*'}).qs.count(), 2)
+        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary_link,name=Sky'}).qs.count(), 1)
+        self.assertEqual(ChangesetFilter({'tag_changes': 'highway=tertiary_link,highway=primary'}).qs.count(), 2)
+        self.assertEqual(ChangesetFilter({'tag_changes': 'name=Store,surface=paved'}).qs.count(), 3)
+        self.assertEqual(ChangesetFilter({'tag_changes': 'landuse=residential,waterway=river'}).qs.count(), 0)
+
 
 
 class TestChangesetAreaLowerThan(TestCase):