fix(event_handler): serialize pydantic/dataclasses in exception handler

[heitorlessa]

Issue number: #3451

Summary

This PR changes Powertools JSON Encoder to always serialize pydantic v1/v2 and dataclasses. This addresses an issue for the new data validation feature in Event Handler, where customers might return a Pydantic model as a response in the exception handler.

Changes

Please provide a summary of what's being changed

User experience

Please share what the user experience looks like before and after this change

from typing import List

import requests
from pydantic import BaseModel, Field

from aws_lambda_powertools import Logger, Tracer
from aws_lambda_powertools.event_handler import APIGatewayRestResolver, Response, content_types
from aws_lambda_powertools.utilities.typing import LambdaContext

tracer = Tracer()
logger = Logger()
app = APIGatewayRestResolver(enable_validation=True, debug=True)

class ErrorModel(BaseModel):
    status_code:int
    message: str

@app.exception_handler(ValueError)
def handle_invalid_limit_qs(ex: ValueError) -> Response[ErrorModel]:  # receives exception raised
    metadata = {"path": app.current_event.path, "query_strings": app.current_event.query_string_parameters}
    logger.error(f"Malformed request: {ex}", extra=metadata)

    return Response(
        status_code=400,
        content_type=content_types.APPLICATION_JSON,
        body=ErrorModel(
            status_code=400,
            message="Invalid data"
        ),
    )


class Todo(BaseModel):
    userId: int
    id_: int = Field(alias="id")
    title: str
    completed: bool


@app.get("/todos")
def get_todos() -> Response[List[Todo]]:
    todo = requests.get("https://jsonplaceholder.typicode.com/todos")
    todo.raise_for_status()

	return todo


def lambda_handler(event: dict, context: LambdaContext) -> dict:
    return app.resolve(event, context)

Checklist

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• Meet tenets criteria
• I have performed a self-review of this change
• Changes have been tested
• Changes are documented
• PR title follows conventional commit semantics

Is this a breaking change?

RFC issue number:

Checklist:

• Migration process documented
• Implement warnings (if it can live side by side)

Acknowledgment

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Disclaimer: We value your time and bandwidth. As such, any pull requests created on non-triaged issues might not be successful.

[leandrodamascena]

LGTM

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
3.1% Duplication

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 95.42%. Comparing base (99aef19) to head (901c4d5).
⚠️ Report is 2751 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #3455   +/-   ##
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  Coverage    95.41%   95.42%           
========================================
  Files          209      209           
  Lines         9648     9664   +16     
  Branches      1770     1773    +3     
========================================
+ Hits          9206     9222   +16     
  Misses         329      329           
  Partials       113      113           

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