Unknown Procedure Type - Next.js App Router

[alex-streza]

I'm running a project using create-t3-turbo and wanted to add OpenAPI support to trpc routers but I keep getting this error, any help is much appreciated, kinda counting on getting OpenAPI support this way.

@morrow/nextjs:dev:  ⨯ Error: Unknown procedure type
@morrow/nextjs:dev:     at getProcedureType (/Users/alex/Documents/GitHub/morrow/node_modules/trpc-openapi/dist/utils/procedure.js:26:11)

I went in the procedure.js file to debug and saw that procedure._def doesn't seem to exist in my trpc: next version (11.0.0-next-alpha.149+11361b82d)

I'm not 100% certain if it's because of this but I'm also using trpc in app router and trpc-openapi in pages/api

pages/api/[...trpc].ts

import type { NextApiRequest, NextApiResponse } from "next";
import { createOpenApiNextHandler } from "trpc-openapi";

import { appRouter } from "@morrow/api";
import { createTRPCOpenAPIContext } from "@morrow/api/src/trpc";

const handler = async (req: NextApiRequest, res: NextApiResponse) => {
  return createOpenApiNextHandler({
    router: appRouter,
    createContext: () => createTRPCOpenAPIContext(),
    onError({ error, path }) {
      console.error(`>>> tRPC OpenAPI Error on '${path}'`, error);
    },
    responseMeta: undefined,
  })(req, res);
};

export default handler;

trpc.ts

/**
 * YOU PROBABLY DON'T NEED TO EDIT THIS FILE, UNLESS:
 * 1. You want to modify request context (see Part 1)
 * 2. You want to create a new middleware or type of procedure (see Part 3)
 *
 * tl;dr - this is where all the tRPC server stuff is created and plugged in.
 * The pieces you will need to use are documented accordingly near the end
 */
import type { NextApiRequest } from "next";
import type {
  SignedInAuthObject,
  SignedOutAuthObject,
} from "@clerk/clerk-sdk-node";
import { getAuth } from "@clerk/nextjs/server";
import { initTRPC, TRPCError } from "@trpc/server";
import superjson from "superjson";
import type { OpenApiMeta } from "trpc-openapi";
import { ZodError } from "zod";

import { prisma } from "@morrow/db";

import { cloudflare } from "./cloudflare";

/**
 * 1. CONTEXT
 *
 * This section defines the "contexts" that are available in the backend API
 *
 * These allow you to access things like the database, the session, etc, when
 * processing a request
 *
 */

interface CreateContextOptions {
  auth?: SignedInAuthObject | SignedOutAuthObject;
}

/**
 * This helper generates the "internals" for a tRPC context. If you need to use
 * it, you can export it from here
 *
 * Examples of things you may need it for:
 * - testing, so we dont have to mock Next.js' req/res
 * - trpc's `createSSGHelpers` where we don't have req/res
 * @see https://create.t3.gg/en/usage/trpc#-servertrpccontextts
 */
const createInnerTRPCContext = (_opts: CreateContextOptions) => {
  return { ..._opts, prisma, cloudflare };
};

export const createTRPCOpenAPIContext = () => {
  return createInnerTRPCContext({});
};

export const createTRPCContext = (_opts: { req: Request }) => {
  return createInnerTRPCContext({
    auth: getAuth(_opts.req as unknown as NextApiRequest),
  });
};

/**
 * 2. INITIALIZATION
 *
 * This is where the trpc api is initialized, connecting the context and
 * transformer
 */
const t = initTRPC
  .context<typeof createTRPCContext>()
  .meta<OpenApiMeta>()
  .create({
    transformer: superjson,
    errorFormatter({ shape, error }) {
      return {
        ...shape,
        data: {
          ...shape.data,
          zodError:
            error.cause instanceof ZodError ? error.cause.flatten() : null,
        },
      };
    },
  });

/**
 * 3. ROUTER & PROCEDURE (THE IMPORTANT BIT)
 *
 * These are the pieces you use to build your tRPC API. You should import these
 * a lot in the /src/server/api/routers folder
 */

/**
 * This is how you create new routers and subrouters in your tRPC API
 * @see https://trpc.io/docs/router
 */
export const createTRPCRouter = t.router;

/**
 * Public (unauthed) procedure
 *
 * This is the base piece you use to build new queries and mutations on your
 * tRPC API. It does not guarantee that a user querying is authorized, but you
 * can still access user session data if they are logged in
 */
export const publicProcedure = t.procedure;

// check if the user is signed in, otherwise throw a UNAUTHORIZED CODE
const isAuthed = t.middleware(({ next, ctx }) => {
  if (!ctx.auth.userId) {
    throw new TRPCError({ code: "UNAUTHORIZED" });
  }
  return next({
    ctx: {
      auth: ctx.auth,
    },
  });
});

/**
 * Protected (authed) procedure
 *
 * If you want a query or mutation to ONLY be accessible to logged in users, use
 * this. It verifies the session is valid and guarantees ctx.session.user is not
 * null
 *
 * @see https://trpc.io/docs/procedures
 */

export const protectedProcedure = t.procedure.use(isAuthed);

[riazosama]

Facing the same issue. Any update on this?

[mulyoved]

see fix

https://github.com/jlalmes/trpc-openapi/issues/434#issuecomment-1936587096

[Vercjames]

Forked and Added support for Next.js 14. https://github.com/Vercjames/package-trpc-swagger

[kdy1]

I made https://www.npmjs.com/package/next-trpc-openapi

[KiranMantha]

@jlalmes / @alex-streza, i faced the same issue when i'm trying to use this via nest application. the issue lies in procedure.ts:getProcedureType method. the latest @trpc/server is emitting procedure definition as below:

 [AsyncFunction: procedure] {
  _def: {
    procedure: true,
    inputs: [],
    middlewares: [ [AsyncFunction: resolveMiddleware] ],
    meta: { openapi: [Object] },
    type: 'query',
    resolver: [Function (anonymous)]
  }
} 

currently this is the method implementation:

const getProcedureType = (procedure: OpenApiProcedure): ProcedureType => {
  if (procedure._def.query) return 'query';
  if (procedure._def.mutation) return 'mutation';
  if (procedure._def.subscription) return 'subscription';
  throw new Error('Unknown procedure type');
};

changing this to below:

const getProcedureType = (procedure: OpenApiProcedure): ProcedureType => {
  if (procedure._def.query) return 'query';
  if (procedure._def.mutation) return 'mutation';
  if (procedure._def.subscription) return 'subscription';
  if (procedure._def.type) return procedure._def.type; // return type if it exists on _def without breaking existing functionality
  throw new Error('Unknown procedure type');
};

may solve this issue.

This is the basic stackblitz app to reproduce this.

PS: i'm using @trpc/server@next version.