Proxy HTTP requests using fetch()

In Bun, fetch supports sending requests through an HTTP or HTTPS proxy. This is useful on corporate networks or when you need to ensure a request is sent through a specific IP address.

await fetch("https://example.com", {
  // The URL of the proxy server
  proxy: "https://username:password@proxy.example.com:8080",
});

The proxy option can be a URL string or an object with url and optional headers. The URL can include the username and password if the proxy requires authentication. It can be http:// or https://.

Custom proxy headers

To send custom headers to the proxy server (useful for proxy authentication tokens, custom routing, etc.), use the object format:

await fetch("https://example.com", {
  proxy: {
    url: "https://proxy.example.com:8080",
    headers: {
      "Proxy-Authorization": "Bearer my-token",
      "X-Proxy-Region": "us-east-1",
    },
  },
});

The headers property accepts a plain object or a Headers instance. These headers are sent directly to the proxy server in CONNECT requests (for HTTPS targets) or in the proxy request (for HTTP targets).

If you provide a Proxy-Authorization header, it will override any credentials specified in the proxy URL.

Environment variables

You can also set the $HTTP_PROXY or $HTTPS_PROXY environment variable to the proxy URL. This is useful when you want to use the same proxy for all requests.

$ HTTPS_PROXY=https://username:password@proxy.example.com:8080 bun run index.ts