Authentication errors in context in GraphQL - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an authentication error in GraphQL context?

An authentication error occurs when a user tries to access a GraphQL API without valid credentials or tokens, causing the server to reject the request.

beginner

How is authentication information typically passed in a GraphQL request context?

Authentication info is usually passed via HTTP headers (like Authorization) and then added to the GraphQL context object for resolvers to check.

intermediate

Why should authentication errors be handled in the GraphQL context?

Handling authentication errors in context centralizes security checks, making it easier to reject unauthorized requests before resolver logic runs.

intermediate

What is a common way to signal an authentication error in GraphQL?

Throwing an AuthenticationError (from packages like apollo-server-errors) which sends a clear error message and HTTP 401 status to the client.

beginner

How can you protect a GraphQL resolver from unauthorized access?

Check the user's authentication status in the context before running resolver logic; if unauthorized, throw an authentication error.

Where is authentication data usually stored for GraphQL resolvers to access?

A In the client-side cookies only

B In the query string

C In the GraphQL context object

D In the database schema

Authentication data is passed in HTTP headers and then added to the GraphQL context object for resolvers to use.

What HTTP status code is commonly returned for authentication errors in GraphQL?

A 401

B 200

C 404

D 500

401 Unauthorized is the standard status code for authentication errors.

Which package is often used to throw authentication errors in Apollo Server?

A graphql-tools

B jsonwebtoken

C express-session

D apollo-server-errors

apollo-server-errors provides AuthenticationError to signal auth failures.

What happens if a resolver does not check authentication in context?

A The server crashes

B The resolver runs normally, possibly exposing data

C The client automatically retries

D The query is blocked by default

Without checks, unauthorized users may access sensitive data.

Why is it better to handle authentication errors early in the GraphQL request lifecycle?

A To reduce unnecessary resolver execution

B To speed up client rendering

C To avoid database schema changes

D To allow anonymous access

Early handling stops unauthorized requests before expensive resolver logic runs.

Explain how authentication errors are detected and handled in the GraphQL context.

Think about where the server checks credentials and how it responds to unauthorized requests.

Describe why it is important to check authentication in GraphQL resolvers and what could happen if you don't.

Consider the consequences of skipping authentication checks.