Writing Lambda Handlers

Lambda handlers can be wrapped with the awstin.awslambda.lambda_handler() decorator factory, which accepts a parser function as an argument. The parser should accept an AWS event and context, and should return inputs to the wrapped function as a tuple (to be passed in as args) or dict (to be passed in as kwargs).

from awstin.awslambda import lambda_handler

def event_parser(event, context):
    request_id = event["requestContext"]["requestId"]
    memory_limit = context["memory_limit_in_mb"]
    return request_id, memory_limit


@lambda_handler(event_parser)
def handle_custom_event(request_id, memory_limit):
    print(request_id)
    print(memory_limit)

In this way, the event parsing and business logic of Lambda handlers are kept separate.