The update_function_configuration currently returns an empty dict no matter what but certain lambda libraries (ie, Zappa) require a realistic return value... which is simply the current config after being updated.

https://github.com/localstack/localstack/blob/9cba1010dfcbf2b7672df4d7da46b7e8ab287f64/localstack/services/awslambda/lambda_api.py#L872

https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/lambda.html#Lambda.Client.update_function_configuration

There might also be some other magic enriching that result but my quick read-through looks like it's an empty dict.



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'Message': message,
                    'Timestamp': timestamp(format=TIMESTAMP_FORMAT_MILLIS),
                    'MessageAttributes': message_attributes
                }
            }]
        }
        return run_lambda(event=event, context={}, func_arn=func_arn, asynchronous=True)
    except Exception as e:
        LOG.warning('Unable to run Lambda function on SNS message: %s %s' % (e, traceback.format_exc()))
def process_kinesis_records(records, stream_name):
    
    try:
        stream_arn = aws_stack.kinesis_stream_arn(stream_name)
        sources = get_event_sources(source_arn=stream_arn)
        for source in sources:
            arn = source['FunctionArn']
            event = {
                'Records': []
            }
            for rec in records:
                event['Records'].append({
                    'eventID': 'shardId-000000000000:{0}'.format(rec['sequenceNumber']),
                    'eventSourceARN': stream_arn,
                    'kinesis': rec
                })
            run_lambda(event=event, context={}, func_arn=arn)
    except Exception as e:
        LOG.warning('Unable to run Lambda function on Kinesis records: %s %s' % (e, traceback.format_exc()))
def process_sqs_message(message_body, message_attributes, queue_name, region_name=None):