Extract client capabilities values

Author: wendigo

tests/unit/test_client.py

@@ -135,7 +135,7 @@ def assert_headers(headers):
         assert headers[constants.HEADER_SESSION] == ""
         assert headers[constants.HEADER_TRANSACTION] is None
         assert headers[constants.HEADER_TIMEZONE] == timezone
-        assert headers[constants.HEADER_CLIENT_CAPABILITIES] == "PARAMETRIC_DATETIME,SESSION_AUTHORIZATION"
+        assert headers[constants.HEADER_CLIENT_CAPABILITIES] == constants.CLIENT_CAPABILITIES
         assert headers[accept_encoding_header] == accept_encoding_value
         assert headers[client_info_header] == client_info_value
         assert headers[constants.HEADER_ROLE] == (

trino/client.py

@@ -522,7 +522,8 @@ def http_headers(self) -> CaseInsensitiveDict[str]:
             headers[constants.HEADER_ENCODING] = self._client_session.encoding
         else:
             raise ValueError("Invalid type for encoding: expected str or list")
-        headers[constants.HEADER_CLIENT_CAPABILITIES] = 'PARAMETRIC_DATETIME,SESSION_AUTHORIZATION'
+        headers[constants.HEADER_CLIENT_CAPABILITIES] = constants.CLIENT_CAPABILITIES
+
         headers["user-agent"] = f"{constants.CLIENT_NAME}/{__version__}"
         if len(self._client_session.roles.values()):
             headers[constants.HEADER_ROLE] = ",".join(

trino/constants.py

@@ -57,6 +57,9 @@
 HEADER_SET_CATALOG = "X-Trino-Set-Catalog"
 
 HEADER_CLIENT_CAPABILITIES = "X-Trino-Client-Capabilities"
+CLIENT_CAPABILITY_PARAMETRIC_DATETIME = "PARAMETRIC_DATETIME"
+CLIENT_CAPABILITY_SESSION_AUTHORIZATION = "SESSION_AUTHORIZATION"
+CLIENT_CAPABILITIES = ','.join([CLIENT_CAPABILITY_PARAMETRIC_DATETIME, CLIENT_CAPABILITY_SESSION_AUTHORIZATION])
 
 HEADER_AUTHORIZATION_USER = "X-Trino-Authorization-User"
 HEADER_SET_AUTHORIZATION_USER = "X-Trino-Set-Authorization-User"