Logger: inject_lambda_context overrides keys appended before in custom middleware

[heitorlessa]

What were you trying to accomplish?

Have a custom middleware to inject additional keys to the Logger as well as using inject_lambda_context.

@lambda_handler_decorator(trace_execution=True)
def process_booking_handler(
    handler: Callable, event: Dict, context: Any, logger: Logger = None
) -> Callable:
    if logger is None:
        logger = Logger()

    handler = logger.inject_lambda_context(handler)

    logger.info("Injecting and annotating process booking state machine")
    process_booking_context = _build_process_booking_model(event)
    _logger_inject_process_booking_sfn(logger=logger, event=event)
    _tracer_annotate_process_booking_sfn(process_booking_context=process_booking_context)

    return handler(event, context)

Expected Behavior

Have additional key added to the log when structure_logs is used outside the handler e.g. shared file, before the handler

Current Behavior

Any additional key is removed once the handler is executed with inject_lambda_context

Possible Solution

inject_lambda_context is overwriting existing structured logs instead of appending

Steps to Reproduce (for bugs)

1. Use structure_logs before inject_lambda_context is used

Code

    logger = Logger()
    logger.structure_logs(append=True, additional_key="test")

    @logger.inject_lambda_context
    def handler(event, context):
        logger.info("Hello") # will not contain additional_key

    handler({}, lambda_context)

Environment

• Powertools version used: 1.0.0
• Packaging format (Layers, PyPi): PyPi
• AWS Lambda function runtime: Python 3.7
• Debugging logs

How to enable debug mode**

# paste logs here