PYTHON-953, warn when using Session.default_consistency_level, fix docs

beltran · beltran · commit e7f6f9afbaf0 · 2018-03-23T15:19:09.000+01:00
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
@@ -11,6 +11,7 @@ Other
 * Reevaluate MONKEY_PATCH_LOOP in test codebase (PYTHON-903)
 * Remove CASS_SERVER_VERSION and replace it for CASSANDRA_VERSION in tests (PYTHON-910)
 * Refactor CASSANDRA_VERSION to a some kind of version object (PYTHON-915)
+* Warn users when using the deprecated Session.default_consistency_level (PYTHON-953)
 
 
 3.13.0
diff --git a/cassandra/cluster.py b/cassandra/cluster.py
@@ -1936,6 +1936,7 @@ def default_timeout(self, timeout):
     @property
     def default_consistency_level(self):
         """
+        *Deprecated:* use execution profiles instead
         The default :class:`~ConsistencyLevel` for operations executed through
         this session.  This default may be overridden by setting the
         :attr:`~.Statement.consistency_level` on individual statements.
@@ -1950,6 +1951,12 @@ def default_consistency_level(self):
 
     @default_consistency_level.setter
     def default_consistency_level(self, cl):
+        """
+        *Deprecated:* use execution profiles instead
+        """
+        warn("Setting the consistency level at the session level will be removed in 4.0. Consider using "
+             "execution profiles and setting the desired consitency level to the EXEC_PROFILE_DEFAULT profile."
+             , DeprecationWarning)
         self._validate_set_legacy_config('default_consistency_level', cl)
 
     _default_serial_consistency_level = None
diff --git a/docs/getting_started.rst b/docs/getting_started.rst
@@ -328,7 +328,10 @@ replicas of the data you are interacting with need to respond for
 the query to be considered a success.
 
 By default, :attr:`.ConsistencyLevel.LOCAL_ONE` will be used for all queries.
-You can specify a different default for the session on :attr:`.Session.default_consistency_level`.
+You can specify a different default for the session on :attr:`.Session.default_consistency_level`
+if the cluster is configured in legacy mode (not using execution profiles). Otherwise this can
+be done by setting the :attr:`.ExecutionProfile.consistency_level` for the execution profile with key
+:data:`~.cluster.EXEC_PROFILE_DEFAULT`.
 To specify a different consistency level per request, wrap queries
 in a :class:`~.SimpleStatement`:
 
diff --git a/tests/integration/standard/test_cluster.py b/tests/integration/standard/test_cluster.py
@@ -1482,3 +1482,22 @@ def test_deprecation_warnings_meta_refreshed(self):
             self.assertEqual(len(w), 1)
             self.assertIn("Cluster.set_meta_refresh_enabled is deprecated and will be removed in 4.0.",
                           str(w[0].message))
+
+    def test_deprecation_warning_default_consistency_level(self):
+        """
+        Tests the deprecation warning has been added when enabling
+        session the default consistency level to session
+
+        @since 3.14
+        @jira_ticket PYTHON-935
+        @expected_result the deprecation warning is emitted
+
+        @test_category logs
+        """
+        with warnings.catch_warnings(record=True) as w:
+            cluster = Cluster()
+            session = cluster.connect()
+            session.default_consistency_level = ConsistencyLevel.ONE
+            self.assertEqual(len(w), 1)
+            self.assertIn("Setting the consistency level at the session level will be removed in 4.0",
+                          str(w[0].message))
