How to handle error and send response in GraphQL

Question

I was starting with GraphQL and I was unable to comprehend how we can throw errors in GraphQL

I went through a couple of articles on the web but almost all of them use

Answer 1

graphql should be an application level layer that shouldn't (see last paragraph why shouldn't and not doesn't) require http to work. Although in 99% of cases it runs on top of http, because of how convenient it is to do so, graphql is itself a layer 7 protocol.

What does that mean in your case? Well, it means you should not mix concepts from HTTP/REST with concepts from graphql and focus on the latter. The headers error code is a HTTP/REST concept, graphql sends errors in the errors field of the response and the nodejs implementation already catches all your errors and adds them to the list. The HTTP status will be always 200, and your clients shouldn't care and consume your graphql api and not a mix of REST with graphql.

Now, that being said, there are couple of things that REST over HTTP does better. So people, including the developers of Apollo, kinda mixed concepts too, mainly because the graphql standard is not complete (aka, it doesn't have a standard/rule for solving all the problems you might encounter while building an API), so people improvised. Honestly, I wouldn't recommend graphql yet for any serious project. Been there, done that, not worth it. Just stick with REST over HTTP.

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