API error handling in Flask - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of API error handling in Flask?

API error handling in Flask helps manage unexpected problems by sending clear, helpful error messages to users instead of crashing or showing confusing errors.

beginner

How do you create a custom error response in Flask?

You create a custom error response by defining an error handler function with @app.errorhandler(error_code) decorator and returning a JSON response with a message and status code.

beginner

What does the @app.errorhandler decorator do?

The @app.errorhandler decorator tells Flask to run a specific function when a certain error happens, like 404 Not Found or 500 Internal Server Error.

beginner

Why should API error responses use JSON format?

API error responses use JSON so that client apps can easily read and understand the error details and handle them properly, keeping communication clear and consistent.

beginner

What HTTP status code is commonly used for 'Resource Not Found' errors?

The HTTP status code 404 is used to indicate that the requested resource was not found on the server.

Which Flask decorator is used to handle specific HTTP errors?

A @app.errorhandler

B @app.route

C @app.before_request

D @app.after_request

The @app.errorhandler decorator is used to define functions that handle specific HTTP errors.

What should an API return when a requested item is not found?

A HTTP 200 with empty body

B HTTP 500 with server error

C HTTP 301 redirect

D HTTP 404 with JSON error message

APIs should return HTTP 404 status with a JSON error message to clearly indicate the resource was not found.

Why is it important to handle errors in an API?

A To crash the server quickly

B To provide clear feedback to users and clients

C To hide all errors silently

D To slow down the response time

Handling errors properly helps users and client apps understand what went wrong and how to fix it.

Which content type is best for API error responses?

A image/png

B text/html

C application/json

D text/plain

application/json is best because it allows clients to parse error details easily.

What does a 500 HTTP status code indicate?

A Server internal error

B Resource not found

C Client error

D Successful request

500 means the server encountered an unexpected condition that prevented it from fulfilling the request.

Explain how to create a custom error handler in Flask and why it is useful.

Think about how Flask knows what to do when an error happens.

Describe the importance of returning proper HTTP status codes and JSON error messages in API error handling.

Consider how apps talk to each other over the internet.