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Bun

Bun is another JavaScript runtime. It's not Node.js or Deno. Bun includes a trans compiler, we can write the code with TypeScript. Hono also works on Bun.

1. Install Bun

To install bun command, follow the instruction in the official web site.

2. Setup

A starter for Bun is available. Start your project with "create-hono" command.

npm create [email protected] my-app
npm create [email protected] my-app

Move into my-app and install the dependencies.

cd my-app
bun install
cd my-app
bun install

3. Hello World

"Hello World" script is below. Almost the same as writing on other platforms.

ts
import { Hono } from 'hono'

const app = new Hono()
app.get('/', (c) => c.text('Hello Bun!'))

export default {
  port: 3000,
  fetch: app.fetch,
}
import { Hono } from 'hono'

const app = new Hono()
app.get('/', (c) => c.text('Hello Bun!'))

export default {
  port: 3000,
  fetch: app.fetch,
}

4. Run

Run the command.

ts
bun run --hot src/index.ts
bun run --hot src/index.ts

Then, access http://localhost:3000 in your browser.

Serve static files

To server static files, use serveStatic imported from hono/bun.

ts
import { serveStatic } from 'hono/bun'

const app = new Hono()

app.use('/static/*', serveStatic({ root: './' }))
app.use('/favicon.ico', serveStatic({ path: './favicon.ico' }))
app.get('/', (c) => c.text('You can access: /static/hello.txt'))
app.get('*', serveStatic({ path: './static/fallback.txt' }))
import { serveStatic } from 'hono/bun'

const app = new Hono()

app.use('/static/*', serveStatic({ root: './' }))
app.use('/favicon.ico', serveStatic({ path: './favicon.ico' }))
app.get('/', (c) => c.text('You can access: /static/hello.txt'))
app.get('*', serveStatic({ path: './static/fallback.txt' }))

For the above code, it will work well with the following directory structure.

./
├── favicon.ico
├── index.ts
└── static
    ├── demo
    │   └── index.html
    ├── fallback.txt
    ├── hello.txt
    └── images
        └── dinotocat.png
./
├── favicon.ico
├── index.ts
└── static
    ├── demo
    │   └── index.html
    ├── fallback.txt
    ├── hello.txt
    └── images
        └── dinotocat.png

Testing

You can use bun:test for testing on Bun.

ts
import { describe, expect, it } from 'bun:test'
import app from '.'

describe('My first test', () => {
  it('Should return 200 Response', async () => {
    const req = new Request('http://localhost/')
    const res = await app.fetch(req)
    expect(res.status).toBe(200)
  })
})
import { describe, expect, it } from 'bun:test'
import app from '.'

describe('My first test', () => {
  it('Should return 200 Response', async () => {
    const req = new Request('http://localhost/')
    const res = await app.fetch(req)
    expect(res.status).toBe(200)
  })
})

Then, run the command.

bun wiptest index.test.ts
bun wiptest index.test.ts

WARNING

"wiptest" command is a still WIP. "test" command that is not a WIP might be released.

Released under the MIT License.