remove storage engine checks

Author: timgraham

django_mongodb_backend/features.py

@@ -616,16 +616,11 @@ def supports_select_union(self):
     @cached_property
     def supports_transactions(self):
         """
-        Transactions are enabled if the MongoDB configuration supports it:
-        MongoDB must be configured as a replica set or sharded cluster, and
-        the store engine must be WiredTiger.
+        Transactions are enabled if MongoDB is configured as a replica set or a
+        sharded cluster.
         """
         self.connection.ensure_connection()
         client = self.connection.connection.admin
-        hello_response = client.command("hello")
-        is_replica_set = "setName" in hello_response
-        is_sharded_cluster = hello_response.get("msg") == "isdbgrid"
-        if is_replica_set or is_sharded_cluster:
-            engine = client.command("serverStatus").get("storageEngine", {})
-            return engine.get("name") == "wiredTiger"
-        return False
+        hello = client.command("hello")
+        # a replica set or a sharded cluster
+        return "setName" in hello or hello.get("msg") == "isdbgrid"

docs/source/ref/database.rst

@@ -50,10 +50,8 @@ Transactions
 .. versionadded:: 5.2.0b2
 
 Support for :doc:`Django's transactions APIs <django:topics/db/transactions>`
-is enabled if the MongoDB configuration supports them: MongoDB must be
-configured as a :doc:`replica set <manual:replication>` or :doc:`sharded
-cluster <manual:sharding>`, and the store engine must be :doc:`WiredTiger
-<manual:core/wiredtiger>`.
+is enabled if MongoDB is configured as a :doc:`replica set<manual:replication>`
+or a :doc:`sharded cluster <manual:sharding>`.
 
 If transactions aren't supported, query execution uses Django and MongoDB's
 default behavior of autocommit mode. Each query is immediately committed to the

tests/backend_/test_features.py

@@ -18,52 +18,22 @@ def test_replica_set(self):
         def mocked_command(command):
             if command == "hello":
                 return {"setName": "foo"}
-            if command == "serverStatus":
-                return {"storageEngine": {"name": "wiredTiger"}}
             raise Exception("Unexpected command")
 
         with patch("pymongo.synchronous.database.Database.command", wraps=mocked_command):
             self.assertIs(connection.features.supports_transactions, True)
 
-    def test_replica_set_other_storage_engine(self):
-        """No support on a non-wiredTiger replica set."""
-
-        def mocked_command(command):
-            if command == "hello":
-                return {"setName": "foo"}
-            if command == "serverStatus":
-                return {"storageEngine": {"name": "other"}}
-            raise Exception("Unexpected command")
-
-        with patch("pymongo.synchronous.database.Database.command", wraps=mocked_command):
-            self.assertIs(connection.features.supports_transactions, False)
-
     def test_sharded_cluster(self):
-        """A sharded cluster with wiredTiger storage engine supports them."""
+        """A sharded cluster supports transactions."""
 
         def mocked_command(command):
             if command == "hello":
                 return {"msg": "isdbgrid"}
-            if command == "serverStatus":
-                return {"storageEngine": {"name": "wiredTiger"}}
             raise Exception("Unexpected command")
 
         with patch("pymongo.synchronous.database.Database.command", wraps=mocked_command):
             self.assertIs(connection.features.supports_transactions, True)
 
-    def test_sharded_cluster_other_storage_engine(self):
-        """No support on a non-wiredTiger shared cluster."""
-
-        def mocked_command(command):
-            if command == "hello":
-                return {"msg": "isdbgrid"}
-            if command == "serverStatus":
-                return {"storageEngine": {"name": "other"}}
-            raise Exception("Unexpected command")
-
-        with patch("pymongo.synchronous.database.Database.command", wraps=mocked_command):
-            self.assertIs(connection.features.supports_transactions, False)
-
     def test_no_support(self):
         """No support on a non-replica set, non-sharded cluster."""