How to import enum from graphql schema to resolvers

[michalkvasnicak]

Using next.js example https://github.com/vercel/next.js/tree/canary/examples/with-typescript-graphql when I try to do the following:

# lib/type-defs.graphqls

type Query {
  viewer: User!
}

# introduced Test enum
enum Test {
  VALUE_1
  VALUE_2
}

# lib/user.graphqls

type User {
  id: ID!
  name: String!
  status: String!
  val: Test! # used Test enum 
}

then when I try to import Test enum in lib/resolvers.ts

import { QueryResolvers, Test } from './type-defs.graphqls'
import { ResolverContext } from './apollo'

const Query: Required<QueryResolvers<ResolverContext>> = {
  viewer(_parent, _args, _context, _info) {
    return { id: String(1), name: 'John Smith', status: 'cached', val: Test.Value_1 }
  },
}

export default { Query }

I receive webpack error:

Is there any example how to import enums from GraphQL schema to typescript code so I can have them defined only in schema and use generated typescript files in my project?

[michalkvasnicak]

I tried to change webpack configuration to use babel loaders on graphqls files too but it didn't help.

[michalkvasnicak]

@piglovesyou I tried to change schemaLoader.js to be similar to loader.js:

• return content of a generated tsx file from processGraphQLCodegenSchemaLoader()
• set up this.resourcePath to the path of the generated tsx file
• return tsxContent in callback()

it seems to work OK but after yarn build it has problem to construct the schema because typeDefs are missing? Not sure what's happening.

[piglovesyou]

Hi @michalkvasnicak, thank you for pointing it out. So true. ResolverTypes support in graphql-let was originally designed just to get TypeScript types, but it turns out it's not enough. It was because I thought many users would run graphql-tag/loader after 'graphql-let/schema/loader'. But, at least in the Next.js example, it doesn't anymore.

As you said, perhaps we should do the same as .graphql loader. Your third try can be close to a PR we want. I mentioned "ResolverTypes support is experimental" in the docs, so I think we can change the behavior.

[piglovesyou]

• [ ] Let graphql-let/schema/loader return transformed source
• [ ] Modify the docs
• [ ] Mention the breaking change in the release note