Graphql: Interceptors don't make sense when used on GraphQL resolvers.

[vnenkpet]

I'm submitting a...

[ ] Regression 
[x] Bug report
[x] Feature request
[x] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead post your question on Stack Overflow.

Current behavior

When interceptor is applied to a GraphQL resolver class, it is correctly applied to all it's methods. However, if we take the logging interceptor example from the docs (https://docs.nestjs.com/interceptors), we will soon find out that once we ask our GraphQL server for something like this

query {
 comments {
   id
   text
   author {
    id
    name
   }
 }
}

the interceptor is actually called multiple times for each comment's author as the author is a (most likely) @PropertyResolver method on the @Resolver class, which is correctly called for each comment. This makes the logger log "Before" and "After" multiple times in parallel for a single request and then it's impossible to use the interceptor as required.

Expected behavior

We should have a way to bind custom execution logic to before and after GraphQL request.
Or at least document how to do this. I was thinking of using a regular controller with a @Post route method on which an interceptor would be used and would work as an entry point to the GraphQL module, but I don't understand how to do this while using the GraphQLModule (not to mention how it works with subscriptions). Any suggestions?

What is the motivation / use case for changing the behaviour?

The interceptor lose some of their usefulness when used on GraphQL resolvers. One example is if we had a transactional request-scoped database connection provider and wanted to commit the transaction after each GraphQL mutation. If the mutation returns data in any format similar to what's described above, the interceptor would try to commit the transaction multiple times.

Environment

Nest version: 6.1.1

[kamilmysliwiec]

It should be fixed in the @next version ($ npm i @nestjs/graphql@next). You will also have to update @nestjs/core to 6.2.0 ($ npm i @nestjs/[email protected])

[kamilmysliwiec]

Published as 6.2.0 ($ npm i @nestjs/graphql@latest). You will also have to update @nestjs/core to 6.2.0 ($ npm i @nestjs/core@latest)

[lock[bot]]

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