Improve DDB bytes encoding (#10740)

localstack/utils/json.py

@@ -1,3 +1,4 @@
+import base64
 import decimal
 import json
 import logging
@@ -47,11 +48,11 @@ def default(self, o):
 
 
 class BytesEncoder(json.JSONEncoder):
- """Helper class that converts JSON documents with bytes"""
+ """Specialized JSON encoder that encode bytes into Base64 strings."""
 
  def default(self, obj):
  if isinstance(obj, bytes):
- return to_str(obj, errors="replace")
+ return to_str(base64.b64encode(obj))
  return super().default(obj)
 
 

tests/aws/services/lambda_/test_lambda_integration_dynamodbstreams.py

@@ -63,7 +63,6 @@ def _get_lambda_logs_event(function_name, expected_num_events, retries=30):
  "$..TableDescription.ProvisionedThroughput.LastIncreaseDateTime",
  "$..TableDescription.StreamSpecification",
  "$..TableDescription.TableStatus",
- "$..Records..dynamodb.NewImage.binary_key.B",
  "$..Records..dynamodb.SizeBytes",
  "$..Records..eventVersion",
  ],

tests/unit/utils/test_json.py

@@ -0,0 +1,9 @@
+import json
+
+from localstack.utils.json import BytesEncoder
+
+
+def test_json_encoder():
+ payload = {"foo": b"foobar"}
+ result = json.dumps(payload, cls=BytesEncoder)
+ assert result == '{"foo": "Zm9vYmFy"}'