fix JSON serializer and tests with redis-py 6.0

x-ref: redis/redis-py#3622

Author: terencehonles

django_rq/tests/utils.py

@@ -5,15 +5,36 @@ def get_queue_index(name='default'):
     """
     Returns the position of Queue for the named queue in QUEUES_LIST
     """
-    queue_index = None
     connection = get_connection(name)
-    connection_kwargs = connection.connection_pool.connection_kwargs
+    connection_kwargs = dict(connection.connection_pool.connection_kwargs)
+
+    special_case_retry = False
+    if (retry := connection_kwargs.get('retry')) and retry.__class__.__eq__ == object.__eq__:
+        special_case_retry = True
+        del connection_kwargs['retry']
+
     for i in range(0, 100):
         try:
             q = get_queue_by_index(i)
         except AttributeError:
             continue
-        if q.name == name and q.connection.connection_pool.connection_kwargs == connection_kwargs:
-            queue_index = i
-            break
-    return queue_index
+        if q.name == name:
+            # assert that the connection is correct
+            if special_case_retry:
+                q_connection_kwargs = dict(q.connection.connection_pool.connection_kwargs)
+                q_retry = q_connection_kwargs.pop('retry', None)
+                assert q_connection_kwargs == q_connection_kwargs
+                assert retry  # for mypy
+                assert (
+                    q_retry.__class__ == retry.__class__
+                    and q_retry._retries == retry._retries
+                    and set(q_retry._supported_errors) == set(retry._supported_errors)
+                    and q_retry._backoff.__class__ == retry._backoff.__class__
+                    and q_retry._backoff.__dict__ == retry._backoff.__dict__
+                )
+            else:
+                assert q.connection.connection_pool.connection_kwargs == connection_kwargs
+
+            return i
+
+    return None

django_rq/utils.py

@@ -67,9 +67,10 @@ def get_statistics(run_maintenance_tasks=False):
         else:
             oldest_job_timestamp = "-"
 
-        # parse_class and connection_pool are not needed and not JSON serializable
-        connection_kwargs.pop('parser_class', None)
+        # remove unneeded properties which are not serializable in JSON
         connection_kwargs.pop('connection_pool', None)
+        connection_kwargs.pop('parser_class', None)
+        connection_kwargs.pop('retry', None)
 
         queue_data = {
             'name': queue.name,