perf(forwarder): reuse boto3 S3 client across SQS batch records (#1079)

S3EventHandler._get_s3_client() created a new boto3.client("s3") per
record. For a 10-record SQS batch that means 10 client constructions
(service model parsing, session setup, connection pool init).

Extract create_s3_client() as a module-level function, accept an
optional s3_client parameter in S3EventHandler.__init__, and create the
client once in sqs_handler() before the loop.

Backward compatible: callers that omit s3_client get a client created
at construction time.

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: LorisFriedel

aws/logs_monitoring/steps/handlers/s3_handler.py

@@ -38,6 +38,17 @@
 )
 
 
+def create_s3_client():
+    """Create a boto3 S3 client with VPC-aware configuration when applicable."""
+    if DD_USE_VPC:
+        return boto3.client(
+            "s3",
+            os.environ["AWS_REGION"],
+            config=botocore.config.Config(s3={"addressing_style": "path"}),
+        )
+    return boto3.client("s3")
+
+
 class S3EventDataStore:
     def __init__(self):
         self.bucket = None
@@ -48,14 +59,15 @@ def __init__(self):
 
 
 class S3EventHandler:
-    def __init__(self, context, metadata, cache_layer):
+    def __init__(self, context, metadata, cache_layer, s3_client=None):
         self.logger = logging.getLogger()
         self.logger.setLevel(
             logging.getLevelName(os.environ.get("DD_LOG_LEVEL", "INFO").upper())
         )
         self.context = context
         self.metadata = metadata
         self.cache_layer = cache_layer
+        self._s3_client = s3_client or create_s3_client()
         self.multiline_regex_start_pattern = _MULTILINE_REGEX_START_PATTERN
         self.multiline_regex_pattern = _MULTILINE_REGEX_PATTERN
         self.data_store = S3EventDataStore()
@@ -122,26 +134,12 @@ def _add_s3_tags_from_cache(self):
             )
 
     def _extract_data(self):
-        s3_client = self._get_s3_client()
-        response = s3_client.get_object(
+        response = self._s3_client.get_object(
             Bucket=self.data_store.bucket, Key=self.data_store.key
         )
         body = response.get("Body")
         self.data_store.data = body.read()
 
-    def _get_s3_client(self):
-        # Need to use path style to access s3 via VPC Endpoints
-        # https://github.com/gford1000-aws/lambda_s3_access_using_vpc_endpoint#boto3-specific-notes
-        if DD_USE_VPC:
-            s3 = boto3.client(
-                "s3",
-                os.environ["AWS_REGION"],
-                config=botocore.config.Config(s3={"addressing_style": "path"}),
-            )
-        else:
-            s3 = boto3.client("s3")
-        return s3
-
     def _get_structured_lines_for_s3_handler(self):
         self._decompress_data()
 

aws/logs_monitoring/steps/parsing.py

@@ -16,7 +16,7 @@
 )
 from steps.enums import AwsEventSource, AwsEventType, AwsEventTypeKeyword
 from steps.handlers.awslogs_handler import AwsLogsHandler
-from steps.handlers.s3_handler import S3EventHandler
+from steps.handlers.s3_handler import S3EventHandler, create_s3_client
 from telemetry import send_event_metric, set_forwarder_telemetry_tags
 
 logger = logging.getLogger()
@@ -97,14 +97,15 @@ def parse_event_type(event):
 
 # Handle S3 events delivered via SQS (S3 -> SQS or S3 -> SNS -> SQS)
 def sqs_handler(event, context, cache_layer):
+    s3_client = create_s3_client()
     for record in event["Records"]:
         inner_event = _extract_inner_event_from_sqs(record)
         if inner_event is None:
             continue
         # Fresh metadata per SQS record: S3EventHandler mutates metadata
         # (DD_SOURCE, tags, service), so each record needs its own copy.
         metadata = generate_metadata(context)
-        s3_handler = S3EventHandler(context, metadata, cache_layer)
+        s3_handler = S3EventHandler(context, metadata, cache_layer, s3_client=s3_client)
         for log_event in s3_handler.handle(inner_event):
             if isinstance(log_event, dict):
                 yield merge_dicts(log_event, metadata)

aws/logs_monitoring/tests/test_s3_handler.py

@@ -232,17 +232,16 @@ def test_s3_handler_with_sns(self):
         self.assertEqual(self.s3_handler.metadata["ddsource"], "s3")
 
     @patch("caching.cloudwatch_log_group_cache.CloudwatchLogGroupTagsCache.__init__")
-    @patch("steps.handlers.s3_handler.S3EventHandler._get_s3_client")
     def test_s3_tags_added_to_metadata(
         self,
-        mock_get_s3_client,
         mock_cache_init,
     ):
-        mock_get_s3_client.side_effect = MagicMock()
         mock_cache_init.return_value = None
         cache_layer = CacheLayer("")
         cache_layer._s3_tags_cache.get = MagicMock(return_value=["s3_tag:tag_value"])
         self.s3_handler.cache_layer = cache_layer
+        self.s3_handler._extract_data = MagicMock()
+        self.s3_handler.data_store.data = b""
         event = {
             "Records": [
                 {