1 files changed, 78 insertions, 0 deletions
diff --git a/tests/config/test_registration_config.py b/tests/config/test_registration_config.py
new file mode 100644
index 0000000000..17a84d20d8
--- /dev/null
+++ b/tests/config/test_registration_config.py
@@ -0,0 +1,78 @@
+# Copyright 2021 The Matrix.org Foundation C.I.C.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from synapse.config import ConfigError
+from synapse.config.homeserver import HomeServerConfig
+
+from tests.unittest import TestCase
+from tests.utils import default_config
+
+
+class RegistrationConfigTestCase(TestCase):
+    def test_session_lifetime_must_not_be_exceeded_by_smaller_lifetimes(self):
+        """
+        session_lifetime should logically be larger than, or at least as large as,
+        all the different token lifetimes.
+        Test that the user is faced with configuration errors if they make it
+        smaller, as that configuration doesn't make sense.
+        """
+        config_dict = default_config("test")
+
+        # First test all the error conditions
+        with self.assertRaises(ConfigError):
+            HomeServerConfig().parse_config_dict(
+                {
+                    "session_lifetime": "30m",
+                    "nonrefreshable_access_token_lifetime": "31m",
+                    **config_dict,
+                }
+            )
+
+        with self.assertRaises(ConfigError):
+            HomeServerConfig().parse_config_dict(
+                {
+                    "session_lifetime": "30m",
+                    "refreshable_access_token_lifetime": "31m",
+                    **config_dict,
+                }
+            )
+
+        with self.assertRaises(ConfigError):
+            HomeServerConfig().parse_config_dict(
+                {
+                    "session_lifetime": "30m",
+                    "refresh_token_lifetime": "31m",
+                    **config_dict,
+                }
+            )
+
+        # Then test all the fine conditions
+        HomeServerConfig().parse_config_dict(
+            {
+                "session_lifetime": "31m",
+                "nonrefreshable_access_token_lifetime": "31m",
+                **config_dict,
+            }
+        )
+
+        HomeServerConfig().parse_config_dict(
+            {
+                "session_lifetime": "31m",
+                "refreshable_access_token_lifetime": "31m",
+                **config_dict,
+            }
+        )
+
+        HomeServerConfig().parse_config_dict(
+            {"session_lifetime": "31m", "refresh_token_lifetime": "31m", **config_dict}
+        )