Fix connection lifecycle

Author: vgvoleg

tests/test_connections.py

@@ -50,6 +50,18 @@ def _test_isolation_level_read_only(
 
         maybe_await(cursor.execute_scheme("DROP TABLE foo"))
 
+    def _test_commit_rollback_after_begin(self, connection: dbapi.Connection, isolation_level: str) -> None:
+        connection.set_isolation_level(isolation_level)
+
+        for _ in range(10):
+            maybe_await(connection.begin())
+            maybe_await(connection.commit())
+
+        for _ in range(10):
+            maybe_await(connection.begin())
+            maybe_await(connection.rollback())
+
+
     def _test_connection(self, connection: dbapi.Connection) -> None:
         maybe_await(connection.commit())
         maybe_await(connection.rollback())
@@ -377,6 +389,26 @@ def test_isolation_level_read_only(
             connection, isolation_level, read_only
         )
 
+    @pytest.mark.parametrize(
+        ("isolation_level"),
+        [
+            (dbapi.IsolationLevel.SERIALIZABLE),
+            (dbapi.IsolationLevel.AUTOCOMMIT),
+            (dbapi.IsolationLevel.ONLINE_READONLY),
+            (dbapi.IsolationLevel.ONLINE_READONLY_INCONSISTENT),
+            (dbapi.IsolationLevel.STALE_READONLY),
+            (dbapi.IsolationLevel.SNAPSHOT_READONLY),
+        ],
+    )
+    def test_commit_rollback_after_begin(
+        self,
+        isolation_level: str,
+        connection: dbapi.Connection,
+    ) -> None:
+        self._test_commit_rollback_after_begin(
+            connection, isolation_level
+        )
+
     def test_connection(self, connection: dbapi.Connection) -> None:
         self._test_connection(connection)
 
@@ -448,6 +480,29 @@ async def test_isolation_level_read_only(
             read_only,
         )
 
+    @pytest.mark.asyncio
+    @pytest.mark.parametrize(
+        ("isolation_level"),
+        [
+            (dbapi.IsolationLevel.SERIALIZABLE),
+            (dbapi.IsolationLevel.AUTOCOMMIT),
+            (dbapi.IsolationLevel.ONLINE_READONLY),
+            (dbapi.IsolationLevel.ONLINE_READONLY_INCONSISTENT),
+            (dbapi.IsolationLevel.STALE_READONLY),
+            (dbapi.IsolationLevel.SNAPSHOT_READONLY),
+        ],
+    )
+    async def test_commit_rollback_after_begin(
+        self,
+        isolation_level: str,
+        connection: dbapi.AsyncConnection,
+    ) -> None:
+        await greenlet_spawn(
+            self._test_commit_rollback_after_begin,
+            connection,
+            isolation_level
+        )
+
     @pytest.mark.asyncio
     async def test_connection(self, connection: dbapi.AsyncConnection) -> None:
         await greenlet_spawn(self._test_connection, connection)

ydb_dbapi/connections.py

@@ -234,20 +234,22 @@ def begin(self) -> None:
 
     @handle_ydb_errors
     def commit(self) -> None:
-        if self._tx_context and self._tx_context.tx_id:
+        if self._tx_context:
             settings = self._get_request_settings()
             self._tx_context.commit(settings=settings)
-            self._session_pool.release(self._session)
             self._tx_context = None
+        if self._session:
+            self._session_pool.release(self._session)
             self._session = None
 
     @handle_ydb_errors
     def rollback(self) -> None:
-        if self._tx_context and self._tx_context.tx_id:
+        if self._tx_context:
             settings = self._get_request_settings()
             self._tx_context.rollback(settings=settings)
-            self._session_pool.release(self._session)
             self._tx_context = None
+        if self._session:
+            self._session_pool.release(self._session)
             self._session = None
 
     @handle_ydb_errors
@@ -424,21 +426,23 @@ async def begin(self) -> None:
 
     @handle_ydb_errors
     async def commit(self) -> None:
-        if self._session and self._tx_context and self._tx_context.tx_id:
+        if self._tx_context:
             settings = self._get_request_settings()
             await self._tx_context.commit(settings=settings)
+            self._tx_context = None
+        if self._session:
             await self._session_pool.release(self._session)
             self._session = None
-            self._tx_context = None
 
     @handle_ydb_errors
     async def rollback(self) -> None:
-        if self._session and self._tx_context and self._tx_context.tx_id:
+        if self._tx_context:
             settings = self._get_request_settings()
             await self._tx_context.rollback(settings=settings)
+            self._tx_context = None
+        if self._session:
             await self._session_pool.release(self._session)
             self._session = None
-            self._tx_context = None
 
     @handle_ydb_errors
     async def close(self) -> None: