Add extra handling to sorting with recommended and relevance

docs/topics/api/addons.rst

@@ -81,7 +81,10 @@ This endpoint allows you to search through public add-ons.
             rating  Bayesian rating, descending.
        recommended  Recommended add-ons above non-recommend add-ons. Only
                     available combined with another sort - ignored on its own.
-         relevance  Search query relevance, descending.
+                    Also ignored if combined with relevance as it already takes
+                    into account recommended status.
+         relevance  Search query relevance, descending.  Ignored without a
+                    query.
            updated  Last updated date, descending.
              users  Average number of daily users, descending.
     ==============  ==========================================================

src/olympia/search/filters.py

@@ -859,7 +859,7 @@ class SortingFilter(BaseFilterBackend):
     def filter_queryset(self, request, qs, view):
         search_query_param = request.GET.get('q')
         sort_param = request.GET.get('sort')
-        order_by = None
+        split_sort_params = None
 
         if sort_param is not None:
             split_sort_params = sort_param.split(',')
@@ -891,11 +891,21 @@ class SortingFilter(BaseFilterBackend):
                         'when the "featured" or "recommended" parameter is '
                         'also present, and the "q" parameter absent.')
 
-            # Having just recommended sort doesn't make any sense, so ignore it
-            if sort_param == 'recommended':
-                sort_param = None
+            # Sorting by relevance only makes sense with a query string
+            if not search_query_param and 'relevance' in split_sort_params:
+                split_sort_params = [
+                    param for param in split_sort_params if not 'relevance']
 
-        if sort_param is None:
+            # Having just recommended sort doesn't make any sense, so ignore it
+            if split_sort_params == ['recommended']:
+                split_sort_params = None
+            # relevance already takes into account recommended so ignore it too
+            elif ('recommended' in split_sort_params and
+                  'relevance' in split_sort_params):
+                split_sort_params = [
+                    param for param in split_sort_params if not 'recommended']
+
+        if not split_sort_params:
             # The default sort depends on the presence of a query: we sort by
             # relevance if we have a query, otherwise by recommended,downloads.
             recommended_waffle_on = switch_is_active(

src/olympia/search/tests/test_filters.py

@@ -401,9 +401,12 @@ class TestSortingFilter(FilterTestsBase):
         SORTING_PARAMS.pop('random')  # Tested separately below.
         SORTING_PARAMS.pop('recommended')  # Tested separately below.
 
-        for param in SORTING_PARAMS:
+        for param, es in SORTING_PARAMS.items():
             qs = self._filter(data={'sort': param})
-            assert qs['sort'] == [self._reformat_order(SORTING_PARAMS[param])]
+            if param == 'relevance':
+                # relevance without q is ignored so default downloads is used
+                es = SORTING_PARAMS['downloads']
+            assert qs['sort'] == [self._reformat_order(es)]
         # Having a search query does not change anything, the requested sort
         # takes precedence.
         for param in SORTING_PARAMS:
@@ -496,6 +499,19 @@ class TestSortingFilter(FilterTestsBase):
             self._reformat_order('-is_recommended'),
             self._reformat_order('-average_daily_users')]
 
+    @override_switch('api-recommendations-priority', active=True)
+    def test_sort_recommended_and_relevance(self):
+        # with a q, recommended with relevance sort, recommended is ignored.
+        qs = self._filter(
+            data={'q': 'something', 'sort': 'recommended,relevance'})
+        assert qs['sort'] == [self._reformat_order('_score')]
+
+        # except if you don't specify a query, then it falls back to default
+        qs = self._filter(data={'sort': 'recommended,relevance'})
+        assert qs['sort'] == [
+            self._reformat_order('-is_recommended'),
+            self._reformat_order('-average_daily_users')]
+
 
 class TestSearchParameterFilter(FilterTestsBase):
     filter_classes = [SearchParameterFilter]