Get excluded segments from session and don't check them again

src/wagtail_personalisation/adapters.py

@@ -66,17 +66,21 @@ class SessionSegmentsAdapter(BaseSegmentsAdapter):
         self.request.session.setdefault('segments', [])
         self._segment_cache = None
 
-    def get_segments(self):
+    def get_segments(self, key="segments"):
         """Return the persistent segments stored in the request session.
 
+        :param key: The key under which the segments are stored
+        :type key: String
         :returns: The segments in the request session
         :rtype: list of wagtail_personalisation.models.Segment or empty list
 
         """
-        if self._segment_cache is not None:
+        if key == "segments" and self._segment_cache is not None:
             return self._segment_cache
 
-        raw_segments = self.request.session['segments']
+        if key not in self.request.session:
+            return []
+        raw_segments = self.request.session[key]
         segment_ids = [segment['id'] for segment in raw_segments]
 
         segments = (
@@ -86,7 +90,8 @@ class SessionSegmentsAdapter(BaseSegmentsAdapter):
             .in_bulk(segment_ids))
 
         retval = [segments[pk] for pk in segment_ids if pk in segments]
-        self._segment_cache = retval
+        if key == "segments":
+            self._segment_cache = retval
         return retval
 
     def set_segments(self, segments, key="segments"):
@@ -174,14 +179,15 @@ class SessionSegmentsAdapter(BaseSegmentsAdapter):
         rule_models = AbstractBaseRule.get_descendant_models()
 
         current_segments = self.get_segments()
-        excluded_segments = []
+        excluded_segments = self.get_segments("excluded_segments")
 
         # Run tests on all remaining enabled segments to verify applicability.
         additional_segments = []
         for segment in enabled_segments:
             if segment.is_static and segment.static_users.filter(id=self.request.user.id).exists():
                 additional_segments.append(segment)
-            elif segment.excluded_users.filter(id=self.request.user.id).exists():
+            elif (segment.excluded_users.filter(id=self.request.user.id).exists() or
+                    segment in excluded_segments):
                 continue
             elif not segment.is_static or not segment.is_full:
                 segment_rules = []