api: Support filtering series by reviewer

We'd like to filter by reviewer, including series with no reviewer.

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>

docs/rest.rst

@@ -293,6 +293,9 @@ A series has then ``n`` revisions, ``n`` going from ``1`` to ``version``.
     :query submitter: Filter series by submitter ``id``. ``self`` can be used
                       as a special value meaning the current logged in user.
 
+    :query reviewer: Filter series by reviewer ``id`` or ``null`` for no
+                     reviewer assigned.
+
     :query submitted_since: Retrieve only submitted series newer than a
                             specified time. Format is the same as ``submitted``
                             in response, an ISO 8601 date.
@@ -571,8 +574,9 @@ API Revisions
 
   - /series/${id}/revisions/${version}/test-results/
 
-- Add the `submitter`, `submitted_since`, `updated_since`, `submitted_before`
-  and `updated_before` query parameters to the list of series entry points.
+- Add the `submitter`, `reviewer`, `submitted_since`, `updated_since`,
+  `submitted_before` and `updated_before` query parameters to the list of
+  series entry points.
 
 **Revision 2**
 

patchwork/views/api.py

@@ -146,11 +146,21 @@ def submitter_filter(self, queryset, submitter):
                 queryset = queryset.filter(submitter__in=people)
         return queryset
 
+    def reviewer_filter(queryset, reviewer):
+        try:
+            reviewer = int(reviewer)
+            queryset = queryset.filter(reviewer=reviewer)
+        except ValueError:
+            if reviewer == 'null':
+                queryset = queryset.filter(reviewer__isnull=True)
+        return queryset
+
     submitted_since = django_filters.CharFilter(action=submitted_since_filter)
     updated_since = django_filters.CharFilter(action=updated_since_filter)
     submitted_before = django_filters.CharFilter(action=submitted_before_filter)
     updated_before = django_filters.CharFilter(action=updated_before_filter)
     submitter = django_filters.MethodFilter(action='submitter_filter')
+    reviewer = django_filters.MethodFilter(action=reviewer_filter)
 
     class Meta:
         model = Series