Middlewares

Middlewares are functions that can be used to modify requests and responses. By default, Toruk provides multiple middlewares to help you handle common tasks.

Middlewares can be registered at the app level or at the route level, by using use keyword.

import { App } from 'https://deno.land/x/toruk/mod.ts'
import { cors } from 'https://deno.land/x/toruk/middlewares/mod.ts'

// Affects all routes
new App({
  routes: [ /* ... */ ],
  use: [
    cors(),
  ]
}).serve()

// Affects only '/user' route
new App({
  routes: [
    {
      path: '/user',
      handler: () => new Response('Hello World!'),
      use: [
        cors(),
      ]
    }
  ]
}).serve()

Execution

They are executed in the order they are registered and can run before or/and after the route handler.

import { App } from 'https://deno.land/x/toruk/mod.ts'
import { cors, jwt } from 'https://deno.land/x/toruk/middlewares/mod.ts'

new App({
  routes: [ /* ... */ ],
  use: [
    cors(),
    jwt(),
  ]
}).serve()

Nesting

Child routes share middlewares with their parent uses them. This allows for common patterns as protected routes.

{
  path: '/private',
  children: [{
      path: '/user',
      handler: () => new Response('User Profile')
  }],
  use: [
    jwt(),
  ]
}

Parameters

Middlewares can emit parameters that can be used by the route handler.

Each middleware provides typings. You can combine them with Handler to strongly type the parameters.

import type { Handler } from 'https://deno.land/x/toruk/mod.ts'
import type { UseJWT } from 'https://deno.land/x/toruk/middlewares/mod.ts'

const handler: Handler<'/private/me/username', [ UseJWT ]> = async ({ jwt }) => {
  return Response.json({ username: jwt.payload.username })
}