How to share typescript types between plugins && resolvers

[Warxcell]

for example, how to fix following error, given this plugin:

const amazonTraceIdPlugin: Plugin<{ amazonTraceId: string | undefined | null }> = {
  onPluginInit: ({ addPlugin }) => {
    addPlugin(useExtendContext((contextValue) => {
        const amazonTraceId = contextValue.request?.headers?.get('x-amzn-trace-id');
        return {
          amazonTraceId: amazonTraceId
        }
      })
    )

    addPlugin(usePayloadFormatter((result, executionArgs) => {
      result.extensions = {
        ...(result.extensions ?? {}),
        ...{ amazonTraceId: executionArgs.contextValue.amazonTraceId }
      }
      return result;
    }))
  }
}

 error TS2345: Argument of type 'Plugin<{}>' is not assignable to parameter of type 'Plugin<{ amazonTraceId: string | null | undefined; }>'.
  Types of property 'onPluginInit' are incompatible.
    Type 'OnPluginInitHook<{}> | undefined' is not assignable to type 'OnPluginInitHook<{ amazonTraceId: string | null | undefined; }> | undefined'.
      Type 'OnPluginInitHook<{}>' is not assignable to type 'OnPluginInitHook<{ amazonTraceId: string | null | undefined; }>'.
        Types of parameters 'options' and 'options' are incompatible.
          Type 'OnPluginInitEventPayload<{ amazonTraceId: string | null | undefined; }>' is not assignable to type 'OnPluginInitEventPayload<{}>'.
            Types of property 'plugins' are incompatible.
              Type 'Plugin<{ amazonTraceId: string | null | undefined; }>[]' is not assignable to type 'Plugin<{}>[]'.
                Type 'Plugin<{ amazonTraceId: string | null | undefined; }>' is not assignable to type 'Plugin<{}>'.
                  Types of property 'onEnveloped' are incompatible.
                    Type 'OnEnvelopedHook<{ amazonTraceId: string | null | undefined; }> | undefined' is not assignable to type 'OnEnvelopedHook<{}> | undefined'.
                      Type 'OnEnvelopedHook<{ amazonTraceId: string | null | undefined; }>' is not assignable to type 'OnEnvelopedHook<{}>'.
                        Types of parameters 'options' and 'options' are incompatible.
                          Type 'OnEnvelopedHookEventPayload<{}>' is not assignable to type 'OnEnvelopedHookEventPayload<{ amazonTraceId: string | null | undefined; }>'.
                            Types of property 'context' are incompatible.
                              Type 'Readonly<Maybe<{}>>' is not assignable to type 'Readonly<Maybe<{ amazonTraceId: string | null | undefined; }>>'.
                                Property 'amazonTraceId' is missing in type 'Readonly<{}>' but required in type 'Readonly<{ amazonTraceId: string | null | undefined; }>'.

Also: after usage of several plugins, how to get final context type in resolvers ? (through graphql codegen)

[EmrysMyrddin]

Hi, can you share more of your setup code ? Like the code creating the yoga server ?

The idea to share context type in your server is to define you context once and use it for every plugin.

Here a basic example:

import { YogaInitialContext, createYoga, createSchema } from 'graphql-yoga';
import { loadFilesSync } from '@graphql-tools/load-files';
import { otherPluginUsingContext } from './otherPlugin' 
import { Resolvers } from './schema.graphql' // import the Resolver type of your generated file

interface GraphqlContext {
  amazonTraceId?: string
  // add any other custom context fields that are used by other plugins
}

type Context = GraphQLContext & YogaInitialContext

const resolvers: Resolver<Context> = {
  exampleResolver: (_, __, ctx) => {
    // Here, ctx have the right type, including `amazonTraceId` field
  }
}

const amazonTraceIdPlugin: Plugin<Context> = {
  onPluginInit: ({ addPlugin }) => {
    addPlugin(useExtendContext(({ request }) => ({
      amazonTraceId: request?.headers?.get('x-amzn-trace-id')
    })),

    addPlugin(usePayloadFormatter((result, { contextValue }) => {
      result.extensions = { ...result.extensions, amazonTraceId: contextValue.amazonTraceId }
      return result;
    }))
  }
}

const yoga = createYoga<YogaInitialContext, GraphqlContext>({
  schema: createSchema({ 
    typeDefs: loadFilesSync('./schema.graphql'),
    resolvers
  }),
  plugins: [
    amazonTraceIdPlugin,
    otherPluginUsingContext<GraphqlContext>(),
  ]
})

[Warxcell]

Its graphql-mesh, creating yoga server happens somewhere unknown. :)

[EmrysMyrddin]

Aah sorry, didn't understood that!

Can you provide more information about how you get this error ? It's when you start your mesh server ?

[Warxcell]

I'm just using tsc --noEmit to verify all types are correct. Basically the code should be self-enough/contained - it provides additional context, and later it uses it.

And btw - the issue with that way of sharing context is that if you remove some plugin - nothing will prevent you to push the code - and it will stop working, because type is there, but the runtime is not.