mirror of
https://github.com/oven-sh/bun
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8618b32c0c
Co-authored-by: Michael H <git@riskymh.dev> Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com> Co-authored-by: Marko Vejnovic <marko@bun.com>
158 lines
3.6 KiB
Markdown
158 lines
3.6 KiB
Markdown
Let's write a simple HTTP server using the built-in `Bun.serve` API. First, create a fresh directory.
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```bash
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$ mkdir quickstart
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$ cd quickstart
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```
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Run `bun init` to scaffold a new project. It's an interactive tool; for this tutorial, just press `enter` to accept the default answer for each prompt.
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```bash
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$ bun init
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? Select a project template - Press return to submit.
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❯ Blank
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React
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Library
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✓ Select a project template: Blank
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+ .gitignore
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+ index.ts
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+ tsconfig.json (for editor autocomplete)
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+ README.md
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To get started, run:
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bun run index.ts
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bun install v$BUN_LATEST_VERSION
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+ @types/bun@$BUN_LATEST_VERSION
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+ typescript@5.9.2
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7 packages installed
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```
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Since our entry point is a `*.ts` file, Bun generates a `tsconfig.json` for you. If you're using plain JavaScript, it will generate a [`jsconfig.json`](https://code.visualstudio.com/docs/languages/jsconfig) instead.
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## Run a file
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Open `index.ts` and paste the following code snippet, which implements a simple HTTP server with [`Bun.serve`](https://bun.com/docs/api/http).
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```ts
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const server = Bun.serve({
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port: 3000,
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fetch(req) {
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return new Response("Bun!");
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},
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});
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console.log(`Listening on http://localhost:${server.port} ...`);
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```
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{% details summary="Seeing TypeScript errors on `Bun`?" %}
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If you used `bun init`, Bun will have automatically installed Bun's TypeScript declarations and configured your `tsconfig.json`. If you're trying out Bun in an existing project, you may see a type error on the `Bun` global.
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To fix this, first install `@types/bun` as a dev dependency.
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```sh
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$ bun add -d @types/bun
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```
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Then add the following to your `compilerOptions` in `tsconfig.json`:
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```json#tsconfig.json
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{
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"compilerOptions": {
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"lib": ["ESNext"],
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"target": "ESNext",
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"module": "Preserve",
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"moduleDetection": "force",
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"moduleResolution": "bundler",
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"allowImportingTsExtensions": true,
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"verbatimModuleSyntax": true,
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"noEmit": true,
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}
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}
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```
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{% /details %}
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Run the file from your shell.
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```bash
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$ bun index.ts
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Listening on http://localhost:3000 ...
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```
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Visit [http://localhost:3000](http://localhost:3000) to test the server. You should see a simple page that says "Bun!".
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## Run a script
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Bun can also execute `"scripts"` from your `package.json`. Add the following script:
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```json-diff
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{
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"name": "quickstart",
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"module": "index.ts",
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"type": "module",
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"private": true,
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+ "scripts": {
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+ "start": "bun run index.ts"
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+ },
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"devDependencies": {
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"@types/bun": "latest"
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},
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"peerDependencies": {
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"typescript": "^5"
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}
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}
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```
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Then run it with `bun run start`.
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```bash
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$ bun run start
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$ bun run index.ts
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Listening on http://localhost:3000 ...
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```
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{% callout %}
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⚡️ **Performance** — `bun run` is roughly 28x faster than `npm run` (6ms vs 170ms of overhead).
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{% /callout %}
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## Install a package
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Let's make our server a little more interesting by installing a package. First install the `figlet` package and its type declarations. Figlet is a utility for converting strings into ASCII art.
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```bash
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$ bun add figlet
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$ bun add -d @types/figlet # TypeScript users only
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```
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Update `index.ts` to use `figlet` in the `fetch` handler.
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```ts-diff
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+ import figlet from "figlet";
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const server = Bun.serve({
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port: 3000,
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fetch(req) {
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+ const body = figlet.textSync("Bun!");
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+ return new Response(body);
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- return new Response("Bun!");
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},
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});
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```
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Restart the server and refresh the page. You should see a new ASCII art banner.
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```txt
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____ _
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| __ ) _ _ _ __ | |
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| _ \| | | | '_ \| |
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| |_) | |_| | | | |_|
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|____/ \__,_|_| |_(_)
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```
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