feat(event_handler): add exception handling mechanism for AppSyncResolver

[leandrodamascena]

Issue number: #2184

Summary

Changes

This PR introduces a new feature to handle exceptions in AppSyncResolver using a standard error handling mechanism, similar to the one used for HTTP Resolvers. Currently, there is no built-in support for exception handling in AppSyncResolver, and this PR aims to address that gap.

Changes

1. Added exception catching function: A new decorator @app.exception_handler has been implemented to catch and handle exceptions raised during the execution of AppSync resolvers. This decorator allows developers to define custom error handling logic based on the type of exception raised.

2. Added tests: Test cases have been added to ensure the proper functioning of the exception handling mechanism and to maintain code quality.

3. Added documentation: The usage and implementation details of the @app.exception_handler decorator have been documented to provide guidance for developers who wish to utilize this new feature.

Note

It's important to note that this exception handling mechanism is not supported when using single async resolvers.

User experience

from aws_lambda_powertools.event_handler import AppSyncResolver

app = AppSyncResolver()

@app.exception_handler(ValueError)
def handle_value_error(ex: ValueError):
    return {"message": "error"}

@app.resolver(field_name="createSomething")
def create_something(id: str):
    raise ValueError("Error")

def lambda_handler(event, context):
    return app.resolve(event, context)

Checklist

If your change doesn't seem to apply, please leave them unchecked.

• 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.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.16%. Comparing base (150623b) to head (d4950b2).
Report is 3 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #5588   +/-   ##
========================================
  Coverage    96.16%   96.16%           
========================================
  Files          229      229           
  Lines        10836    10853   +17     
  Branches      2015     2018    +3     
========================================
+ Hits         10420    10437   +17     
  Misses         327      327           
  Partials        89       89           

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