bun-types/docs/guides/http/stream-file.mdx

Type definitions and documentation for Bun, an incredibly fast JavaScript runtime

---
title: Stream a file as an HTTP Response
sidebarTitle: Stream file response
mode: center
---

This snippet reads a file from disk using [`Bun.file()`](/docs/runtime/file-io#reading-files-bun-file). This returns a `BunFile` instance, which can be passed directly into the `new Response` constructor.

```ts server.ts icon="/icons/typescript.svg"
const path = "/path/to/file.txt";
const file = Bun.file(path);
const resp = new Response(file);
```

---

The `Content-Type` is read from the file and automatically set on the `Response`.

```ts server.ts icon="/icons/typescript.svg"
new Response(Bun.file("./package.json")).headers.get("Content-Type");
// => application/json;charset=utf-8

new Response(Bun.file("./test.txt")).headers.get("Content-Type");
// => text/plain;charset=utf-8

new Response(Bun.file("./index.tsx")).headers.get("Content-Type");
// => text/javascript;charset=utf-8

new Response(Bun.file("./img.png")).headers.get("Content-Type");
// => image/png
```

---

Putting it all together with [`Bun.serve()`](/docs/runtime/http/server).

```ts server.ts icon="/icons/typescript.svg"
// static file server
Bun.serve({
  async fetch(req) {
    const path = new URL(req.url).pathname;
    const file = Bun.file(path);
    return new Response(file);
  },
});
```

---

See [Docs > API > File I/O](/docs/runtime/file-io#writing-files-bun-write) for complete documentation of `Bun.write()`.