googleapis · asthamohta · May 24, 2023 · Apr 20, 2023 · Apr 27, 2023 · Apr 27, 2023
@@ -17,6 +17,7 @@
 import datetime
 import decimal
 import math
+import time
 
 from google.protobuf.struct_pb2 import ListValue
 from google.protobuf.struct_pb2 import Value
@@ -294,6 +295,59 @@ def _metadata_with_prefix(prefix, **kw):
     return [("google-cloud-resource-prefix", prefix)]
 
 
+def _retry(
+    func,
+    retry_count=5,
+    delay=2,
+    allowed_exceptions=None,
+):
+    """
+    Retry a function with a specified number of retries, delay between retries, and list of allowed exceptions.
+
+    Args:
+        func: The function to be retried.
+        retry_count: The maximum number of times to retry the function.
+        delay: The delay in seconds between retries.
+        allowed_exceptions: A tuple of exceptions that are allowed to occur without triggering a retry.
+                            Passing allowed_exceptions as None will lead to retrying for all exceptions.
+
+    Returns:
+        The result of the function if it is successful, or raises the last exception if all retries fail.
+    """
+    retries = 0
+    while retries <= retry_count:
+        try:
+            return func()
+        except Exception as exc:
+            if (
+                allowed_exceptions is None or exc.__class__ in allowed_exceptions
+            ) and retries < retry_count:
+                if (
+                    allowed_exceptions is not None
+                    and allowed_exceptions[exc.__class__] is not None
+                ):
+                    allowed_exceptions[exc.__class__](exc)
+                time.sleep(delay)
+                delay = delay * 2
+                retries = retries + 1
+            else:
+                raise exc
+
+
+def _check_rst_stream_error(exc):
+    resumable_error = (
+        any(
+            resumable_message in exc.message
+            for resumable_message in (
+                "RST_STREAM",
+                "Received unexpected EOS on DATA frame from server",
+            )
+        ),
+    )
+    if not resumable_error:
+        raise
+
+
 def _metadata_with_leader_aware_routing(value, **kw):
     """Create RPC metadata containing a leader aware routing header
 

@@ -13,6 +13,7 @@
 # limitations under the License.
 
 """Context manager for Cloud Spanner batched writes."""
+import functools
 
 from google.cloud.spanner_v1 import CommitRequest
 from google.cloud.spanner_v1 import Mutation
@@ -26,6 +27,9 @@
 )
 from google.cloud.spanner_v1._opentelemetry_tracing import trace_call
 from google.cloud.spanner_v1 import RequestOptions
+from google.cloud.spanner_v1._helpers import _retry
+from google.cloud.spanner_v1._helpers import _check_rst_stream_error
+from google.api_core.exceptions import InternalServerError
 
 
 class _BatchBase(_SessionWrapper):
@@ -186,10 +190,15 @@ def commit(self, return_commit_stats=False, request_options=None):
             request_options=request_options,
         )
         with trace_call("CloudSpanner.Commit", self._session, trace_attributes):
-            response = api.commit(
+            method = functools.partial(
+                api.commit,
                 request=request,
                 metadata=metadata,
             )
+            response = _retry(
+                method,
+                allowed_exceptions={InternalServerError: _check_rst_stream_error},
+            )
         self.committed = response.commit_timestamp
         self.commit_stats = response.commit_stats
         return self.committed

@@ -29,13 +29,15 @@
 from google.api_core.exceptions import ServiceUnavailable
 from google.api_core.exceptions import InvalidArgument
 from google.api_core import gapic_v1
-from google.cloud.spanner_v1._helpers import _make_value_pb
-from google.cloud.spanner_v1._helpers import _merge_query_options
 from google.cloud.spanner_v1._helpers import (
+    _make_value_pb,
+    _merge_query_options,
     _metadata_with_prefix,
     _metadata_with_leader_aware_routing,
+    _retry,
+    _check_rst_stream_error,
+    _SessionWrapper,
 )
-from google.cloud.spanner_v1._helpers import _SessionWrapper
 from google.cloud.spanner_v1._opentelemetry_tracing import trace_call
 from google.cloud.spanner_v1.streamed import StreamedResultSet
 from google.cloud.spanner_v1 import RequestOptions
@@ -560,12 +562,17 @@ def partition_read(
         with trace_call(
             "CloudSpanner.PartitionReadOnlyTransaction", self._session, trace_attributes
         ):
-            response = api.partition_read(
+            method = functools.partial(
+                api.partition_read,
                 request=request,
                 metadata=metadata,
                 retry=retry,
                 timeout=timeout,
             )
+            response = _retry(
+                method,
+                allowed_exceptions={InternalServerError: _check_rst_stream_error},
+            )
 
         return [partition.partition_token for partition in response.partitions]
 
@@ -659,12 +666,17 @@ def partition_query(
             self._session,
             trace_attributes,
         ):
-            response = api.partition_query(
+            method = functools.partial(
+                api.partition_query,
                 request=request,
                 metadata=metadata,
                 retry=retry,
                 timeout=timeout,
             )
+            response = _retry(
+                method,
+                allowed_exceptions={InternalServerError: _check_rst_stream_error},
+            )
 
         return [partition.partition_token for partition in response.partitions]
 
@@ -791,10 +803,15 @@ def begin(self):
             )
         txn_selector = self._make_txn_selector()
         with trace_call("CloudSpanner.BeginTransaction", self._session):
-            response = api.begin_transaction(
+            method = functools.partial(
+                api.begin_transaction,
                 session=self._session.name,
                 options=txn_selector.begin,
                 metadata=metadata,
             )
+            response = _retry(
+                method,
+                allowed_exceptions={InternalServerError: _check_rst_stream_error},
+            )
         self._transaction_id = response.id
         return self._transaction_id
@@ -22,6 +22,8 @@
     _merge_query_options,
     _metadata_with_prefix,
     _metadata_with_leader_aware_routing,
+    _retry,
+    _check_rst_stream_error,
 )
 from google.cloud.spanner_v1 import CommitRequest
 from google.cloud.spanner_v1 import ExecuteBatchDmlRequest
@@ -33,6 +35,7 @@
 from google.cloud.spanner_v1._opentelemetry_tracing import trace_call
 from google.cloud.spanner_v1 import RequestOptions
 from google.api_core import gapic_v1
+from google.api_core.exceptions import InternalServerError
 
 
 class Transaction(_SnapshotBase, _BatchBase):
@@ -102,7 +105,11 @@ def _execute_request(
         transaction = self._make_txn_selector()
         request.transaction = transaction
         with trace_call(trace_name, session, attributes):
-            response = method(request=request)
+            method = functools.partial(method, request=request)
+            response = _retry(
+                method,
+                allowed_exceptions={InternalServerError: _check_rst_stream_error},
+            )
 
         return response
 
@@ -132,8 +139,15 @@ def begin(self):
             )
         txn_options = TransactionOptions(read_write=TransactionOptions.ReadWrite())
         with trace_call("CloudSpanner.BeginTransaction", self._session):
-            response = api.begin_transaction(
-                session=self._session.name, options=txn_options, metadata=metadata
+            method = functools.partial(
+                api.begin_transaction,
+                session=self._session.name,
+                options=txn_options,
+                metadata=metadata,
+            )
+            response = _retry(
+                method,
+                allowed_exceptions={InternalServerError: _check_rst_stream_error},
             )
         self._transaction_id = response.id
         return self._transaction_id
@@ -153,11 +167,16 @@ def rollback(self):
                     )
                 )
             with trace_call("CloudSpanner.Rollback", self._session):
-                api.rollback(
+                method = functools.partial(
+                    api.rollback,
                     session=self._session.name,
                     transaction_id=self._transaction_id,
                     metadata=metadata,
                 )
+                _retry(
+                    method,
+                    allowed_exceptions={InternalServerError: _check_rst_stream_error},
+                )
         self.rolled_back = True
         del self._session._transaction
 
@@ -212,10 +231,15 @@ def commit(self, return_commit_stats=False, request_options=None):
             request_options=request_options,
         )
         with trace_call("CloudSpanner.Commit", self._session, trace_attributes):
-            response = api.commit(
+            method = functools.partial(
+                api.commit,
                 request=request,
                 metadata=metadata,
             )
+            response = _retry(
+                method,
+                allowed_exceptions={InternalServerError: _check_rst_stream_error},
+            )
         self.committed = response.commit_timestamp
         if return_commit_stats:
             self.commit_stats = response.commit_stats

@@ -170,7 +170,7 @@ def test__session_checkout(self, mock_database):
         connection._session_checkout()
         self.assertEqual(connection._session, "db_session")
 
-    def test__session_checkout_database_error(self):
+    def test_session_checkout_database_error(self):
         from google.cloud.spanner_dbapi import Connection
 
         connection = Connection(INSTANCE)
@@ -191,7 +191,7 @@ def test__release_session(self, mock_database):
         pool.put.assert_called_once_with("session")
         self.assertIsNone(connection._session)
 
-    def test__release_session_database_error(self):
+    def test_release_session_database_error(self):
         from google.cloud.spanner_dbapi import Connection
 
         connection = Connection(INSTANCE)

@@ -14,6 +14,7 @@
 
 
 import unittest
+import mock
 
 
 class Test_merge_query_options(unittest.TestCase):
@@ -671,6 +672,83 @@ def test(self):
         self.assertEqual(metadata, [("google-cloud-resource-prefix", prefix)])
 
 
+class Test_retry(unittest.TestCase):
+    class test_class:
+        def test_fxn(self):
+            return True
+
+    def test_retry_on_error(self):
+        from google.api_core.exceptions import InternalServerError, NotFound
+        from google.cloud.spanner_v1._helpers import _retry
+        import functools
+
+        test_api = mock.create_autospec(self.test_class)
+        test_api.test_fxn.side_effect = [
+            InternalServerError("testing"),
+            NotFound("testing"),
+            True,
+        ]
+
+        _retry(functools.partial(test_api.test_fxn))
+
+        self.assertEqual(test_api.test_fxn.call_count, 3)
+
+    def test_retry_allowed_exceptions(self):
+        from google.api_core.exceptions import InternalServerError, NotFound
+        from google.cloud.spanner_v1._helpers import _retry
+        import functools
+
+        test_api = mock.create_autospec(self.test_class)
+        test_api.test_fxn.side_effect = [
+            NotFound("testing"),
+            InternalServerError("testing"),
+            True,
+        ]
+
+        with self.assertRaises(InternalServerError):
+            _retry(
+                functools.partial(test_api.test_fxn),
+                allowed_exceptions={NotFound: None},
+            )
+
+        self.assertEqual(test_api.test_fxn.call_count, 2)
+
+    def test_retry_count(self):
+        from google.api_core.exceptions import InternalServerError
+        from google.cloud.spanner_v1._helpers import _retry
+        import functools
+
+        test_api = mock.create_autospec(self.test_class)
+        test_api.test_fxn.side_effect = [
+            InternalServerError("testing"),
+            InternalServerError("testing"),
+        ]
+
+        with self.assertRaises(InternalServerError):
+            _retry(functools.partial(test_api.test_fxn), retry_count=1)
+
+        self.assertEqual(test_api.test_fxn.call_count, 2)
+
+    def test_check_rst_stream_error(self):
+        from google.api_core.exceptions import InternalServerError
+        from google.cloud.spanner_v1._helpers import _retry, _check_rst_stream_error
+        import functools
+
+        test_api = mock.create_autospec(self.test_class)
+        test_api.test_fxn.side_effect = [
+            InternalServerError("Received unexpected EOS on DATA frame from server"),
+            InternalServerError("RST_STREAM"),
+            True,
+        ]
+
+        _retry(
+            functools.partial(test_api.test_fxn),
+            allowed_exceptions={InternalServerError: _check_rst_stream_error},
+        )
+
+        self.assertEqual(test_api.test_fxn.call_count, 3)
+
+
 class Test_metadata_with_leader_aware_routing(unittest.TestCase):
     def _call_fut(self, *args, **kw):
         from google.cloud.spanner_v1._helpers import _metadata_with_leader_aware_routing