Bug: event_parser decorator catches an irrelevant AttributeError and raises InvalidModelTypeError exception.

[junkor-1011]

Expected Behaviour

The expected behavior is that exceptions related to Powertools do not arise from the event_parser decorator in code like the following:

from aws_lambda_powertools.utilities.parser import event_parser
from pydantic import BaseModel


class EventModel(BaseModel):
    """It's just a sample, so the content can be anything."""
    val: str


@event_parser(model=EventModel)
def lambda_handler(event: EventModel, context):
    print(event)  # correctly parsed

    a = "aaa"
    a.property  # raise AttributeError (**NOT related to event_parser**)


# The following is intended for simple reproduction in a local environment:
if __name__ == "__main__":
    lambda_handler({"val": "hello, lambda"}, None)

Assume that the event is in a format that matches the EventModel by pydantic and is correctly parsed.
Therefore, the exception happening in the above code has nothing to do with powertools event_parser.

Current Behaviour

InvalidModelTypeError occurs within powertools, as shown below:

raise InvalidModelTypeError(f"Error: {str(exc)}. Please ensure the type you're trying to parse into is correct")
aws_lambda_powertools.utilities.parser.exceptions.InvalidModelTypeError: Error: 'str' object has no attribute 'property'. Please ensure the type you're trying to parse into is correct

I consider it very confusing because even if the event validation in the event_parser decorator succeeds, the above exception is raised.

Code snippet

Same as described in “Expected Behaviour”.

Possible Solution

Currently (v3.3.0), AttributeError is caught at the error location in powertools as follows:

https://github.com/aws-powertools/powertools-lambda-python/blob/v3.3.0/aws_lambda_powertools/utilities/parser/parser.py#L114

Is it problematic to rewrite this part to catch Pydantic-derived Exceptions (e.g. pydantic.ValidationError) instead of AttributeError?

Steps to Reproduce

• Python version: 3.12
• architecture: x86_64
• The libraries used are the same versions as those installed by the following requirements.txt file:

# requirements.txt
annotated-types==0.7.0
aws-lambda-powertools==3.3.0
jmespath==1.0.1
pydantic==2.10.3
pydantic-core==2.27.1
typing-extensions==4.12.2

Powertools for AWS Lambda (Python) version

3.3.0

AWS Lambda function runtime

3.12

Packaging format used

PyPi

Debugging logs

[boring-cyborg]

Thanks for opening your first issue here! We'll come back to you as soon as we can.
In the meantime, check out the #python channel on our Powertools for AWS Lambda Discord: Invite link

[anafalcao]

Hey @junkor-1011 ! Thank you so much for opening this issue. We'll evaluate and get back to you soon. 🚀

[github-actions]

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[github-actions]

This is now released under 3.4.0 version!