Error handling on client in GraphQL - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main purpose of error handling on the client in GraphQL?

To detect and manage errors returned by the GraphQL server, ensuring the user gets clear feedback and the app can respond gracefully.

beginner

In GraphQL, where are errors typically found in the response?

Errors are usually found in the errors field of the GraphQL response JSON, separate from the data field.

intermediate

How can a client handle partial data when a GraphQL response contains both data and errors?

The client can use the available data to update the UI and also show error messages for the parts that failed, allowing partial success handling.

beginner

What is a common method to catch network or server errors in a GraphQL client?

Using try-catch blocks around the fetch or client request, or handling promise rejections, to catch errors like network failures or server downtime.

intermediate

Why is it important to differentiate between GraphQL errors and network errors on the client?

Because GraphQL errors mean the server processed the request but found issues, while network errors mean the request didn't reach or get a response from the server. Handling them differently improves user experience.

Where does a GraphQL client find errors in a typical response?

A In the 'headers' field

B In the 'status' field

C In the 'errors' field

D In the 'data' field only

GraphQL responses include an 'errors' field when there are errors, separate from the 'data' field.

What should a client do if a GraphQL response has both 'data' and 'errors'?

A Use the data and show error messages for failed parts

B Ignore the data and show only errors

C Discard the entire response

D Retry the request immediately

Clients can use partial data and inform users about errors to provide a better experience.

Which of these is a network error example in GraphQL client context?

A Query syntax error

B Server returns 500 status

C Field not found in schema

D No internet connection

No internet connection is a network error; others are GraphQL or server errors.

How can a client catch network errors when making GraphQL requests?

A Using try-catch or promise rejection handlers

B By checking the 'errors' field in response

C By validating the query before sending

D By inspecting the 'data' field

Network errors occur outside the GraphQL response and are caught via try-catch or promise rejection.

Why handle GraphQL errors and network errors differently on the client?

A Because network errors contain error messages

B Because GraphQL errors mean server processed request; network errors mean no response

C Because GraphQL errors never affect UI

D Because network errors are always temporary

Understanding error types helps the client respond appropriately and inform the user correctly.

Explain how a GraphQL client should handle a response that contains both data and errors.

Think about showing what works and informing about what failed.

Describe the difference between GraphQL errors and network errors from a client perspective.

Consider where the error happens and what it means for the app.