fix(providers/oracle): use conn.schema as service_name fallback in OracleHook (apache#62895)

* fix(providers/oracle): use conn.schema as service_name fallback in OracleHook

When creating an Oracle connection via the UI with Host, Port, and Schema
fields filled but without explicitly setting service_name in extras,
get_conn() built the DSN without a service name, causing TNS errors.

Now conn.schema is used as the service_name when neither service_name
nor sid is set in connection extras.

Fixes apache#62526

* ci: retrigger CI (unrelated static check failures)

* fix: remove thick_mode from schema_as_service_name test to avoid CI Oracle client dependency

Author: YoannAbriel

providers/oracle/src/airflow/providers/oracle/hooks/oracle.py

@@ -216,6 +216,10 @@ def get_conn(self) -> oracledb.Connection:
 
         # Set up DSN
         service_name = conn.extra_dejson.get("service_name")
+        # Fall back to conn.schema as service_name when not explicitly set in extras.
+        # The UI Schema field maps to conn.schema which is the Oracle service name.
+        if not service_name and not sid and schema:
+            service_name = schema
         port = conn.port if conn.port else DEFAULT_DB_PORT
         if conn.host and sid and not service_name:
             conn_config["dsn"] = oracledb.makedsn(conn.host, port, sid)

providers/oracle/tests/unit/oracle/hooks/test_oracle.py

@@ -141,6 +141,36 @@ def test_get_conn_expire_time(self, mock_connect):
         assert args == ()
         assert kwargs["expire_time"] == 10
 
+    @mock.patch("airflow.providers.oracle.hooks.oracle.oracledb.connect")
+    def test_get_conn_schema_as_service_name(self, mock_connect):
+        """When service_name and sid are not in extras, conn.schema should be used as service_name."""
+        self.connection.schema = "MY_SERVICE"
+        self.connection.extra = json.dumps({})
+        self.db_hook.get_conn()
+        assert mock_connect.call_count == 1
+        args, kwargs = mock_connect.call_args
+        assert kwargs["dsn"] == oracledb.makedsn("host", 1521, service_name="MY_SERVICE")
+
+    @mock.patch("airflow.providers.oracle.hooks.oracle.oracledb.connect")
+    def test_get_conn_schema_not_used_when_service_name_set(self, mock_connect):
+        """Explicit service_name in extras takes precedence over conn.schema."""
+        self.connection.schema = "MY_SCHEMA"
+        self.connection.extra = json.dumps({"service_name": "EXPLICIT_SVC"})
+        self.db_hook.get_conn()
+        assert mock_connect.call_count == 1
+        args, kwargs = mock_connect.call_args
+        assert kwargs["dsn"] == oracledb.makedsn("host", 1521, service_name="EXPLICIT_SVC")
+
+    @mock.patch("airflow.providers.oracle.hooks.oracle.oracledb.connect")
+    def test_get_conn_schema_not_used_when_sid_set(self, mock_connect):
+        """Explicit sid in extras takes precedence over conn.schema."""
+        self.connection.schema = "MY_SCHEMA"
+        self.connection.extra = json.dumps({"sid": "MY_SID"})
+        self.db_hook.get_conn()
+        assert mock_connect.call_count == 1
+        args, kwargs = mock_connect.call_args
+        assert kwargs["dsn"] == oracledb.makedsn("host", 1521, "MY_SID")
+
     @mock.patch("airflow.providers.oracle.hooks.oracle.oracledb.connect")
     def test_set_current_schema(self, mock_connect):
         self.connection.schema = "schema_name"