Add support for reporting batch item failures

README.rst

@@ -66,7 +66,13 @@ Batch Mode
 ----------
 If the event source send multiple records to be processed, the layer will execute your handler one time for each record.
 To disable this behaviour, just create a variable called ``BATCH_REQUEST`` with value ``TRUE``. This option only works 
-if the ``THREADING_ENABLED`` was not set to ``TRUE``
+if the ``THREADING_ENABLED`` was not set to ``TRUE``.
+
+Reporting batch item failures (https://aws.amazon.com/about-aws/whats-new/2021/11/aws-lambda-partial-batch-response-sqs-event-source/)
+----------
+If the event source send multiple records to be processed, the layer can handle the partial batch item failures.
+To enable this feature, just create a variable called ``PARTIAL_BATCH_RESPONSE`` with value ``TRUE``. This option only works 
+if the ``THREADING_ENABLED`` was not set to ``TRUE``.
 
 Logging
 -------

phhelper/aws_lambda_helper.py

@@ -138,6 +138,22 @@ def __records_handler(f, event, context):
 
     return True
 
+def __partial_batch_records_handler(f, event, context):
+    batch_item_failures = []
+    batch_response = {}
+
+    for record in event['Records']:
+        try:
+            f(record, context)
+        except Exception as error:
+            batch_item_failures.append({"itemIdentifier": record['messageId']})
+
+            logging.error('lambda_handler error: %s' % (error))
+            logging.error('lambda_handler trace: %s' % traceback.format_exc())
+
+    batch_response["batchItemFailures"] = batch_item_failures
+    return batch_response
+
 def __cognito_handler(f, event, context):
     result = None
     try:
@@ -223,11 +239,15 @@ def generic_handler(event, context):
             if (thread_enabled == 'TRUE'):
                 __thread_records_handler(f, event, context)
             else:
-                batch_request = str(os.environ.get('BATCH_REQUEST','FALSE')).upper()
-                if (batch_request == 'TRUE'):
-                    return __batch_handler(f, event, context)
+                partial_batch_response = str(os.environ.get('PARTIAL_BATCH_RESPONSE','FALSE')).upper()
+                if (partial_batch_response == 'TRUE'):
+                    return __partial_batch_records_handler(f, event, context)
                 else:
-                    __records_handler(f, event, context)
+                    batch_request = str(os.environ.get('BATCH_REQUEST','FALSE')).upper()
+                    if (batch_request == 'TRUE'):
+                        return __batch_handler(f, event, context)
+                    else:
+                        __records_handler(f, event, context)
         elif 'requestContext' in event:
             return __apigateway_handler(f, event, context)
         elif 'source' in event and event['source'] == 'aws.events':

setup.py

@@ -6,7 +6,7 @@
 
 setuptools.setup(
     name='phhelper',
-    version='0.9.23',
+    version='0.9.24',
     author='Luiz Henrique Gomes',
     author_email="lhgnet@gmail.com",
     description='Python Handler Helper for Lambda',