Context

The Context object is passed to every route handler and middleware function. It provides access to the request, response helpers, environment bindings, and context variables.

Constructor

You typically don’t create Context instances directly. Hono creates them for each request.

const c = new Context(request, options?)

Request Properties

req

The HonoRequest instance for accessing request data.

c.req: HonoRequest<P, I['out']>

app.get('/users/:id', (c) => {
  const id = c.req.param('id')
  const query = c.req.query('search')
  return c.json({ id, query })
})

See the HonoRequest API reference for available methods.

env

Environment bindings (e.g., Cloudflare Workers KV, D1, etc.).

c.env: E['Bindings']

app.get('/todos', async (c) => {
  // Access Cloudflare D1 database
  const todos = await c.env.DB.prepare('SELECT * FROM todos').all()
  return c.json(todos)
})

event

The FetchEvent associated with the current request (Cloudflare Workers).

c.event: FetchEventLike

Throws an error if the context does not have a FetchEvent.

app.get('/data', async (c) => {
  // Use waitUntil for async operations that shouldn't block response
  c.event.waitUntil(
    fetch('https://analytics.example.com/track')
  )
  return c.text('OK')
})

executionCtx

The ExecutionContext for the current request.

c.executionCtx: ExecutionContext

Throws an error if the context does not have an ExecutionContext.

app.get('/data', async (c) => {
  c.executionCtx.waitUntil(analyticsTask())
  return c.text('Processing')
})

error

Error object if a handler threw an error (available in error handlers).

c.error: Error | undefined

app.use('*', async (c, next) => {
  await next()
  if (c.error) {
    console.error('Request error:', c.error)
  }
})

finalized

Boolean indicating whether the response has been finalized.

c.finalized: boolean

res

The Response object for the current request.

c.res: Response

app.use('*', async (c, next) => {
  await next()
  console.log('Status:', c.res.status)
})

Response Methods

text

Respond with plain text.

c.text(text, status?, headers?)
c.text(text, init?)

string

required

Text content to send

StatusCode

HTTP status code (default: 200)

HeaderRecord

Additional headers to set

Response

Response with Content-Type: text/plain

app.get('/hello', (c) => {
  return c.text('Hello, World!')
})

app.get('/error', (c) => {
  return c.text('Not Found', 404)
})

json

Respond with JSON.

c.json(object, status?, headers?)
c.json(object, init?)

JSONValue | {}

required

Object to serialize as JSON

StatusCode

HTTP status code (default: 200)

HeaderRecord

Additional headers to set

Response

Response with Content-Type: application/json

app.get('/api/user', (c) => {
  return c.json({ name: 'John', age: 30 })
})

app.post('/api/user', async (c) => {
  const body = await c.req.json()
  return c.json({ created: true }, 201)
})

html

Respond with HTML.

c.html(html, status?, headers?)
c.html(html, init?)

string | Promise<string>

required

HTML content to send

StatusCode

HTTP status code (default: 200)

HeaderRecord

Additional headers to set

Response | Promise<Response>

Response with Content-Type: text/html

app.get('/', (c) => {
  return c.html('<h1>Hello, World!</h1>')
})

app.get('/page', (c) => {
  return c.html(
    <html>
      <body>
        <h1>Welcome</h1>
      </body>
    </html>
  )
})

body

Respond with a raw body.

c.body(data, status?, headers?)
c.body(data, init?)

Data | null

required

Body data (string, ArrayBuffer, ReadableStream, or Uint8Array)

StatusCode

HTTP status code

HeaderRecord

Headers to set

Response

Response with the provided body

app.get('/binary', (c) => {
  const buffer = new Uint8Array([1, 2, 3, 4])
  return c.body(buffer)
})

redirect

Redirect to a different URL.

c.redirect(location, status?)

string | URL

required

URL to redirect to

RedirectStatusCode

HTTP redirect status code (default: 302)

Response

Redirect response with Location header

app.get('/old-path', (c) => {
  return c.redirect('/new-path')
})

app.get('/permanent', (c) => {
  return c.redirect('/new-url', 301)
})

notFound

Return a 404 Not Found response.

c.notFound()

Response

404 Not Found response

app.get('/users/:id', async (c) => {
  const user = await findUser(c.req.param('id'))
  if (!user) {
    return c.notFound()
  }
  return c.json(user)
})

newResponse

Create a new Response with merged headers.

c.newResponse(data, status?, headers?)
c.newResponse(data, init?)

Data | null

required

Response body

StatusCode

HTTP status code

HeaderRecord

Headers to set

Response

New Response with headers merged from c.header() calls

app.get('/data', (c) => {
  c.header('X-Custom', 'value')
  return c.newResponse('Hello', 200)
})

Header Methods

Set a response header.

c.header(name, value?, options?)

string

required

Header name

string

Header value. If undefined, the header is deleted.

SetHeadersOptions

Options object with append boolean

app.get('/data', (c) => {
  c.header('X-Custom', 'value')
  c.header('Content-Type', 'application/json')
  return c.body(JSON.stringify({ data: 'value' }))
})

// Append header
c.header('Set-Cookie', 'token=abc', { append: true })
c.header('Set-Cookie', 'user=john', { append: true })

status

Set the response status code.

c.status(status)

StatusCode

required

HTTP status code to set

app.get('/data', (c) => {
  c.status(201)
  return c.json({ created: true })
})

It’s usually cleaner to pass the status directly to response methods like c.json(data, 201) instead of calling c.status() separately.

Context Variables

Context variables allow you to pass data between middleware and handlers.

set

Set a context variable.

c.set(key, value)

string

required

Variable name

any

required

Value to store

app.use('*', async (c, next) => {
  c.set('requestTime', Date.now())
  c.set('user', { id: 1, name: 'John' })
  await next()
})

get

Get a context variable.

c.get(key)

string

required

Variable name

any

The stored value, or undefined if not set

app.get('/', (c) => {
  const user = c.get('user')
  const time = c.get('requestTime')
  return c.json({ user, time })
})

var

Read-only object containing all context variables.

c.var: Readonly<ContextVariableMap & E['Variables']>

app.get('/', (c) => {
  const { user, requestTime } = c.var
  return c.json({ user, requestTime })
})

c.var provides type-safe access to variables when using TypeScript with proper type definitions.

Rendering Methods

render

Render content using the configured renderer.

c.render(...args)

Response | Promise<Response>

Rendered response

app.get('/', (c) => {
  return c.render('Hello!')
})

setRenderer

Set a custom renderer for the application.

c.setRenderer(renderer)

Renderer

required

Function that renders content to a Response

app.use('*', async (c, next) => {
  c.setRenderer((content) => {
    return c.html(
      <html>
        <body>
          <div>{content}</div>
        </body>
      </html>
    )
  })
  await next()
})

app.get('/', (c) => c.render('Hello!'))
// Renders: <html><body><div>Hello!</div></body></html>

setLayout

Set a layout component.

c.setLayout(layout)

Layout

required

Layout component function

Layout

The layout function

getLayout

Get the current layout.

c.getLayout()

Layout | undefined

The current layout function, or undefined

Type Parameters

The Context class accepts generic type parameters for type safety:

Env

default:"any"

Environment type defining bindings and variables

string

default:"any"

Path parameter type for type-safe param access

Input

default:"{}"

Input type for validated data

type Env = {
  Bindings: {
    DB: D1Database
  }
  Variables: {
    user: User
  }
}

app.get('/users/:id', (c: Context<Env, '/users/:id'>) => {
  const id = c.req.param('id') // Type-safe
  const db = c.env.DB // Type-safe
  const user = c.var.user // Type-safe
  return c.json({ id })
})

Core

Built-in Middleware

Helpers

Routers

Adapters

Client

Context

Context

Constructor

Request Properties

req

env

event

executionCtx

error

finalized

res

Response Methods

text

json

html

body

redirect

notFound

newResponse

Header Methods

header

status

Context Variables

set

get

var

Rendering Methods

render

setRenderer

setLayout

getLayout

Type Parameters

​Context

​Constructor

​Request Properties

​req

​env

​event

​executionCtx

​error

​finalized

​res

​Response Methods

​text

​json

​html

​body

​redirect

​notFound

​newResponse

​Header Methods

​header

​status

​Context Variables

​set

​get

​var

​Rendering Methods

​render

​setRenderer

​setLayout

​getLayout

​Type Parameters

Context

Constructor

Request Properties

req

env

event

executionCtx

error

finalized

res

Response Methods

text

json

html

body

redirect

notFound

newResponse

Header Methods

header

status

Context Variables

set

get

var

Rendering Methods

render

setRenderer

setLayout

getLayout

Type Parameters