tRPC Server Middleware adapts a tRPC server as middleware for Hono. Hono works on almost any JavaScript runtime, including Cloudflare Workers, Deno, and Bun. So, with this middleware, the same code will run as tRPC server.
npm install @hono/trpc-server
Router:
import { initTRPC } from '@trpc/server'
import { z } from 'zod'
const t = initTRPC.create()
const publicProcedure = t.procedure
const router = t.router
export const appRouter = router({
hello: publicProcedure.input(z.string().nullish()).query(({ input }) => {
return `Hello ${input ?? 'World'}!`
}),
})
export type AppRouter = typeof appRouterHono app using tRPC Server Middleware:
import { Hono } from 'hono'
import { trpcServer } from '@hono/trpc-server' // Deno 'npm:@hono/trpc-server'
import { appRouter } from './router'
const app = new Hono()
app.use(
'/trpc/*',
trpcServer({
router: appRouter,
})
)
export default appClient:
import { createTRPCProxyClient, httpBatchLink } from '@trpc/client'
import type { AppRouter } from './router'
const client = createTRPCProxyClient<AppRouter>({
links: [
httpBatchLink({
url: 'http://localhost:8787/trpc',
}),
],
})
console.log(await client.hello.query('Hono'))You can also access c.env from hono context from the trpc ctx. eg. here's an example using cloudflare D1 binding available as env.DB
import { initTRPC } from '@trpc/server'
import { z } from 'zod'
type Env = {
DB: D1Database;
}
type HonoContext = {
env: Env,
};
const t = initTRPC.context<HonoContext>().create()
const publicProcedure = t.procedure
const router = t.router
export const appRouter = router({
usersCount: publicProcedure.query(({ input, ctx }) => {
const result = await ctx.env.DB.prepare("SELECT count(*) from user;").all();
return result.results[0].count;
}),
})
export type AppRouter = typeof appRouterFor further control, you can optionally specify a createContext that in this case will receive the hono context as 2nd argument:
app.use(
'/trpc/*',
trpcServer({
router: appRouter,
createContext: (_opts, c) => ({
// c is the hono context
var1: c.env.MY_VAR1,
var2: c.req.header('X-VAR2'),
})
})
)Yusuke Wada https://github.com/yusukebe
MIT