How can i get the current context type?

[piccinnigius]

Hi, thanks in advance for your awesome work. I have a question, given the following:

export const EmbeddDocumentsAction = os
  .input(EmbeddDocumentsPayload)
  .meta({ actionName: "embed-documents" })
  .use(loggingMiddleware)
  .use(authMiddleware)
  .use(CompanyConfigLoaderMiddleware)
  .handler(async function ({ input: { company_id, documents }, context }) {
    return await EmbeddDocumentsWorker({
      data: { company_id, documents },
      context,
    });
  });

how can i retrieve the context type from EmbeddDocumentsWorker?

[unnoq]

I treat EmbeddDocumentsWorker as an oRPC procedure and using .callable or .actionable at the end.

However, before doing that, you need to remove .callable and .actionable and instead use the call utility:

You can achieve this by applying a middleware:

export const EmbeddDocumentsAction = os
  .handler(async function ({ input: { company_id, documents }, context }) {
    let otherContext;
    
    const result = await call(EmbeddDocumentsWorker.use(({ context, next }) => {
      otherContext = context;
      return next()
    }), { context });
    
    
    return result
  });

[piccinnigius]

sorry for my poor explaination. i have this action that calls EmbeddDocumentsWorker

const EmbeddDocumentsAction = os
  .input(EmbeddDocumentsPayload)
  .meta({ actionName: "embed-documents" })
  .use(loggingMiddleware)
  .use(authMiddleware)
  .use(CompanyConfigLoaderMiddleware)
  .handler(async function ({ input: { company_id, documents }, context }) {
    return await EmbeddDocumentsWorker({
      data: { company_id, documents },
      context,
    });
  });

EmbeddDocumentsWorker is implemented like this:

export const EmbeddDocumentsWorker = async ({
  data,
  context,
}: {
  data: z.infer<typeof EmbeddDocumentsPayload>;
  context: any;
})=> {
//code

}

instead of that any i need to infer and pass the type of the context based on modifications of the middlewares

[unnoq]

I think you should manually define a separate context type instead. oRPC now doesn't has a neat way for this.

Or you can convert EmbeddDocumentsWorker to a procedure and make sure your middleware can safely execute multiple times like this:

const authMiddleware = os
  .$context<{user?: { id: number }}>()
  .middleware(async ({ context, next }) => {
    if (context.user){
      return next({
        context: {
          user: context.user,
        }
      })
    }

    const user = await getUser()

    return next({
      context: {
        user,
      }
    })
  })

[piccinnigius]

i'm not a ts expert, but i've managed to do in this semi-automated way:

type InferContext<T> =
  T extends DecoratedMiddleware<any, infer C, any, any, any, any> ? C : never;

export type BaseContext = {
  startTime: number;
};

type ContextMap = {
  auth: InferContext<typeof authMiddleware>;
  companyConfigLoader: InferContext<typeof CompanyConfigLoaderMiddleware>;
};

type UnionToIntersection<U> = (U extends any ? (k: U) => void : never) extends (
  k: infer I,
) => void
  ? I
  : never;

export type ORPCContext<K extends (keyof ContextMap)[]> = BaseContext &
  UnionToIntersection<ContextMap[K[number]]>;

and then where i need:

const EmbeddDocumentsWorker = async ({
  data,
  context,
}: {
  data: z.infer<typeof EmbeddDocumentsPayload>;
  context: ORPCContext<["auth", "companyConfigLoader"]>;
}) =>{
//rest
}

[unnoq]

Can can confirm InferContext is correct but UnionToIntersection and ORPCContext I'm not sure but if it works it works

[unnoq]

We making utility for it now: #201

[unnoq]

New InferRouterCurrentContexts utils has been available in latest version, please try it.

[unnoq]

Hey @piccinnigius can this solve your problem?

[piccinnigius]

Hi @unnoq, sorry for no feedback, I'll try it later today due to different projects, thanks again

[piccinnigius]

@unnoq i've tried with 1.0.0 beta and 0.48 but i've found too much breaking changes for a fast test, I'll try again when i have a bit more time :/

[unnoq]

1.0.0-beta.5 just drop I recommend you should upgrade now, feel free to DM me if face any issues @piccinnigius