Release Notes

Hono v4.10.0 is now available!

This release brings improved TypeScript support and new utilities.

The main highlight is the enhanced middleware type definitions that solve a long-standing issue with type safety for RPC clients.

Middleware Type Improvements

Imagine the following app:

import { Hono } from 'hono'

const app = new Hono()

const routes = app.get(
  '/',
  (c) => {
    return c.json({ errorMessage: 'Error!' }, 500)
  },
  (c) => {
    return c.json({ message: 'Success!' }, 200)
  }
)

The client with RPC:

import { hc } from 'hono/client'

const client = hc<typeof routes>('/')

const res = await client.index.$get()

if (res.status === 500) {
}

if (res.status === 200) {
}

Previously, it couldn't infer the responses from middleware, so a type error was thrown.

Now the responses are correctly typed.

This was a long-standing issue and we were thinking it was super difficult to resolve it. But now come true.

Thank you for the great work @slawekkolodziej!

cloneRawRequest Utility

The new cloneRawRequest utility allows you to clone the raw Request object after it has been consumed by validators or middleware.

import { cloneRawRequest } from 'hono/request'

app.post('/api', async (c) => {
  const body = await c.req.json()

  // Clone the consumed request
  const clonedRequest = cloneRawRequest(c.req)
  await externalLibrary.process(clonedRequest)
})

Thanks @kamaal111!

New features

feat(types): passing middleware types #4393
feat(ssg): add default plugin that defines the recommended behavior #4394
feat(request): add cloneRawRequest utility for request cloning #4382

All changes

feat(types): passing middleware types by @slawekkolodziej in #4393
feat(ssg): add default plugin that defines the recommended behavior by @3w36zj6 in #4394
feat(request): add cloneRawRequest utility for request cloning by @kamaal111 in #4382
fix(proxy): Correct hop-by-hop header handling per RFC 9110 by @sugar-cat7 in #4459

New Contributors

@slawekkolodziej made their first contribution in #4393
@kamaal111 made their first contribution in #4382

Full Changelog: v4.9.12...v4.10.0

honojs/hono v4.10.0 on GitHub