Route to a different origin based on origin response

export default {
  async fetch(request) {
    // Send original request to the origin
    const response = await fetch(request);

    // If response is not 200 OK or a redirect, send to another origin
    if (!response.ok && !response.redirected) {
      // First, clone the original request to construct a new request
      const newRequest = new Request(request);
      // Add a header to identify a re-routed request at the new origin
      newRequest.headers.set("X-Rerouted", "1");
      // Clone the original URL
      const url = new URL(request.url);
      // Send request to a different origin / hostname
      url.hostname = "example.com";
      // Serve response to the new request from the origin
      return await fetch(url, newRequest);
    }

    // If response is 200 OK or a redirect, serve it
    return response;
  },
};

Was this helpful?

What did you like?

Accurate

Easy to understand

Solved my problem

Helped me decide to use the product

Other

What went wrong?

Hard to understand

Incorrect information

Missing the information

Other

Thank you for helping improve Cloudflare's documentation!