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

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User experience

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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 ✅

Comparison is base (99aef19) 95.41% compared to head (901c4d5) 95.42%.
Report is 1 commits behind head on develop.

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Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #3455   +/-   ##
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  Coverage    95.41%   95.42%           
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  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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