hono

curl -H "Accept: text/markdown" https://hono.dev/docs/helpers/cookie

npm install -D @hono/cli@next
npx hono agent-context

import { Hono } from 'hono'
 
const app = new Hono()
 
// With TypeScript generics
type Env = {
  Bindings: { DATABASE: D1Database; KV: KVNamespace }
  Variables: { user: User }
}
const app = new Hono<Env>()

app.get('/path', handler)
app.post('/path', handler)
app.put('/path', handler)
app.delete('/path', handler)
app.patch('/path', handler)
app.options('/path', handler)
app.all('/path', handler) // all HTTP methods
app.on('PURGE', '/path', handler) // custom method
app.on(['PUT', 'DELETE'], '/path', handler) // multiple methods

// Path parameters
app.get('/user/:name', (c) => {
  const name = c.req.param('name')
  return c.json({ name })
})
 
// Multiple params
app.get('/posts/:id/comments/:commentId', (c) => {
  const { id, commentId } = c.req.param()
})
 
// Optional parameters
app.get('/api/animal/:type?', (c) => c.text('Animal!'))
 
// Wildcards
app.get('/wild/*/card', (c) => c.text('Wildcard'))
 
// Regexp constraints
app.get('/post/:date{[0-9]+}/:title{[a-z]+}', (c) => {
  const { date, title } = c.req.param()
})
 
// Chained routes
app
  .get('/endpoint', (c) => c.text('GET'))
  .post((c) => c.text('POST'))
  .delete((c) => c.text('DELETE'))

// Using route()
const api = new Hono()
api.get('/users', (c) => c.json([]))
 
const app = new Hono()
app.route('/api', api) // mounts at /api/users
 
// Using basePath()
const app = new Hono().basePath('/api')
app.get('/users', (c) => c.json([])) // GET /api/users

app.notFound((c) => c.json({ message: 'Not Found' }, 404))
 
app.onError((err, c) => {
  console.error(err)
  return c.json({ message: 'Internal Server Error' }, 500)
})

c.text('Hello') // text/plain
c.json({ message: 'Hello' }) // application/json
c.html('<h1>Hello</h1>') // text/html
c.redirect('/new-path') // 302 redirect
c.redirect('/new-path', 301) // 301 redirect
c.body('raw body', 200, headers) // raw response
c.notFound() // 404 response

c.status(201)
c.header('X-Custom', 'value')
c.header('Cache-Control', 'no-store')

// In middleware
c.set('user', { id: 1, name: 'Alice' })
 
// In handler
const user = c.get('user')
// or
const user = c.var.user

const value = await c.env.KV.get('key')
const db = c.env.DATABASE
c.executionCtx.waitUntil(promise)

app.use(async (c, next) => {
  c.setRenderer((content) =>
    c.html(
      <html><body>{content}</body></html>
    )
  )
  await next()
})
 
app.get('/', (c) => c.render(<h1>Hello</h1>))

c.req.param('id') // path parameter
c.req.param() // all path params as object
c.req.query('page') // query string parameter
c.req.query() // all query params as object
c.req.queries('tags') // multiple values: ?tags=A&tags=B → ['A', 'B']
c.req.header('Authorization') // request header
c.req.header() // all headers (keys are lowercase)
 
// Body parsing
await c.req.json() // parse JSON body
await c.req.text() // parse text body
await c.req.formData() // parse as FormData
await c.req.parseBody() // parse multipart/form-data or urlencoded
await c.req.arrayBuffer() // parse as ArrayBuffer
await c.req.blob() // parse as Blob
 
// Validated data (used with validator middleware)
c.req.valid('json')
c.req.valid('query')
c.req.valid('form')
c.req.valid('param')
 
// Properties
c.req.url // full URL string
c.req.path // pathname
c.req.method // HTTP method
c.req.raw // underlying Request object

import { cors } from 'hono/cors'
import { logger } from 'hono/logger'
import { basicAuth } from 'hono/basic-auth'
import { prettyJSON } from 'hono/pretty-json'
import { secureHeaders } from 'hono/secure-headers'
import { etag } from 'hono/etag'
import { compress } from 'hono/compress'
import { poweredBy } from 'hono/powered-by'
import { timing } from 'hono/timing'
import { cache } from 'hono/cache'
import { bearerAuth } from 'hono/bearer-auth'
import { jwt } from 'hono/jwt'
import { jwk } from 'hono/jwk'
import { csrf } from 'hono/csrf'
import { ipRestriction } from 'hono/ip-restriction'
import { bodyLimit } from 'hono/body-limit'
import { timeout } from 'hono/timeout'
import { requestId } from 'hono/request-id'
import { methodOverride } from 'hono/method-override'
import { methodNotAllowed } from 'hono/method-not-allowed'
import { languageDetector } from 'hono/language'
import { some, every, except } from 'hono/combine'
import { contextStorage, getContext } from 'hono/context-storage'
import { trailingSlash, trimTrailingSlash } from 'hono/trailing-slash'
 
// Registration
app.use(logger()) // all routes
app.use('/api/*', cors()) // specific path
app.post('/api/*', basicAuth({ username: 'admin', password: 'secret' }))

// Inline
app.use(async (c, next) => {
  const start = Date.now()
  await next()
  const elapsed = Date.now() - start
  c.res.headers.set('X-Response-Time', `${elapsed}ms`)
})
 
// Reusable with createMiddleware
import { createMiddleware } from 'hono/factory'
 
const auth = createMiddleware(async (c, next) => {
  const token = c.req.header('Authorization')
  if (!token) return c.json({ error: 'Unauthorized' }, 401)
  await next()
})
 
app.use('/api/*', auth)

Request → mw1 before → mw2 before → handler → mw2 after → mw1 after → Response

app.use(async (c, next) => {
  // before handler
  await next()
  // after handler
})

import { zValidator } from '@hono/zod-validator'
import { z } from 'zod'
 
const schema = z.object({
  title: z.string().min(1),
  body: z.string()
})
 
app.post('/posts', zValidator('json', schema), (c) => {
  const data = c.req.valid('json') // fully typed
  return c.json(data, 201)
})

import { sValidator } from '@hono/standard-validator'
import * as v from 'valibot'
 
const schema = v.object({ name: v.string(), age: v.number() })
 
app.post('/users', sValidator('json', schema), (c) => {
  const data = c.req.valid('json')
  return c.json(data, 201)
})

{
  "compilerOptions": {
    "jsx": "react-jsx",
    "jsxImportSource": "hono/jsx"
  }
}

import type { PropsWithChildren } from 'hono/jsx'
 
const Layout = (props: PropsWithChildren) => (
  <html>
    <head>
      <title>My App</title>
    </head>
    <body>{props.children}</body>
  </html>
)
 
const UserCard = ({ name }: { name: string }) => (
  <div class="card">
    <h2>{name}</h2>
  </div>
)
 
app.get('/', (c) => {
  return c.html(
    <Layout>
      <UserCard name="Alice" />
    </Layout>
  )
})

const UserList = async () => {
  const users = await fetchUsers()
  return (
    <ul>
      {users.map((u) => (
        <li>{u.name}</li>
      ))}
    </ul>
  )
}

const Items = () => (
  <>
    <li>Item 1</li>
    <li>Item 2</li>
  </>
)

import { stream, streamText, streamSSE } from 'hono/streaming'
 
// Basic stream
app.get('/stream', (c) => {
  return stream(c, async (stream) => {
    stream.onAbort(() => console.log('Aborted'))
    await stream.write(new Uint8Array([0x48, 0x65]))
    await stream.pipe(readableStream)
  })
})
 
// Text stream
app.get('/stream-text', (c) => {
  return streamText(c, async (stream) => {
    await stream.writeln('Hello')
    await stream.sleep(1000)
    await stream.write('World')
  })
})
 
// Server-Sent Events
app.get('/sse', (c) => {
  return streamSSE(c, async (stream) => {
    let id = 0
    while (true) {
      await stream.writeSSE({
        data: JSON.stringify({ time: new Date().toISOString() }),
        event: 'time-update',
        id: String(id++)
      })
      await stream.sleep(1000)
    }
  })
})

// GET
const res = await app.request('/posts')
expect(res.status).toBe(200)
expect(await res.json()).toEqual({ posts: [] })
 
// POST with JSON
const res = await app.request('/posts', {
  method: 'POST',
  body: JSON.stringify({ title: 'Hello' }),
  headers: { 'Content-Type': 'application/json' }
})
 
// POST with FormData
const formData = new FormData()
formData.append('name', 'Alice')
const res = await app.request('/users', { method: 'POST', body: formData })
 
// With mock env (Cloudflare Workers bindings)
const res = await app.request('/api/data', {}, { KV: mockKV, DATABASE: mockDB })
 
// Using Request object
const req = new Request('http://localhost/api', { method: 'DELETE' })
const res = await app.request(req)

// Server: routes MUST be chained to preserve types
const route = app
  .post('/posts', zValidator('json', schema), (c) => {
    return c.json({ ok: true }, 201)
  })
  .get('/posts', (c) => {
    return c.json({ posts: [] })
  })
export type AppType = typeof route
 
// Client: use hc() with the exported type
import { hc } from 'hono/client'
import type { AppType } from './server'
 
const client = hc<AppType>('http://localhost:8787/')
const res = await client.posts.$post({ json: { title: 'Hello' } })
const data = await res.json() // fully typed

import type { InferRequestType, InferResponseType } from 'hono/client'
 
type ReqType = InferRequestType<typeof client.posts.$post>
type ResType = InferResponseType<typeof client.posts.$post, 200>

import { getConnInfo } from 'hono/conninfo'
import { getCookie, setCookie, deleteCookie } from 'hono/cookie'
import { css, Style } from 'hono/css'
import { createFactory } from 'hono/factory'
import { html, raw } from 'hono/html'
import { stream, streamText, streamSSE } from 'hono/streaming'
import { testClient } from 'hono/testing'
import { upgradeWebSocket } from 'hono/cloudflare-workers' // or other adapter

import { createFactory } from 'hono/factory'
 
const factory = createFactory<Env>()
 
// Create app (Env type is inherited)
const app = factory.createApp()
 
// Create middleware (Env type is inherited, no need to pass generics)
const mw = factory.createMiddleware(async (c, next) => {
  await next()
})
 
// Create handlers separately (preserves type inference)
const handlers = factory.createHandlers(logger(), (c) => c.json({ message: 'Hello' }))
app.get('/api', ...handlers)

// Cloudflare Workers / Deno / Bun
export default app
 
// Node.js
import { serve } from '@hono/node-server'
serve(app)
```**