Define an API endpoint

To define a new API endpoint you can either create a new module or add a new endpoint to an existing module.

Create a new module

To create a new module you can create a new folder in the modules folder. For example modules/posts. In this folder create a new sub-folder /procedures with an index.ts file.

Then create a new .ts file for the endpoint in the /procedures folder. For example modules/posts/procedures/published-posts.ts:

import { z } from "zod";
import { publicProcedure } from "../../trpc";
import { db, PostSchema } from "database";

export const publishedPosts = publicProcedure
  .output(z.array(PostSchema))
  .query(async () => {
    const posts = await db.post.findMany({
      where: {
        published: true,
      },
    });

    return posts;
  });

Export endpoint from module

To export the endpoint from the module you need to add it to the /procedures/index.ts file of the module:

export * from "./published-posts";

If you want to add an endpoint to an existing module you can simply add the endpoint to the /procedures folder of the module and export it in the index.ts file.

Register module router

To make the module and it's endpoints available in the API you need to register a router for this module in the /trpc/router.ts file:

import * as postsProcedures from "../posts/procedures";

export const apiRouter = router({
  // ...
  posts: router(postsProcedures),
});