Serverless Scripting Example: Single and Multiple Origin Routing

Overview

You can use this document to learn how to create a script that can:

• Re-route a single URL path to a single, alternate origin 
• Re-route multiple URL paths to multiple origins

Before you begin, you must enable serverless scripting for your stack. To learn more, see Enable Serverless Scripting and Create a Script.

View a sample script for a single path

In the following example, the route is: /de

This script will apply to all requests that have /de in the path. As a result, after you create a script, you need to ensure that all URLs are accessible, or you can adjust the route and script accordingly. 

Review the following sample script: 

addEventListener("fetch", event => {
  event.respondWith(handleRequest(event.request));
});
    
function checkSite(url) {
  return new URL(url).pathname.split('/')[1]; // we're checking the URL path, e.g. domain.com/something/else would yield something
}
    
async function handleRequest(request) {
  try {
    const path = new URL(request.url).pathname; // we need get the url in order to figure out where to route them
    request.url = 'https://sitehash0.stackpathcdn.com' + path;
    return fetch(request);
  } catch (e) {
    return new Response(e.stack || e, { status: 500 }); // error handling
  }
}

Access your script 

You can access your script with any of the delivery domains on your account.

Based on the above example, you can access the script with https://sitehash.stackpathcdn.com/de/index, and then the request will be sent to https://sitehash0.stackpathcdn.com/de/index. 

View sample script for multiple paths

In the following example, the route is: *

This script will apply to all requests to your website. As a result, after you create a script, you need to ensure that all URLs are accessible, or you can adjust the route and script accordingly. 

Review the following script:

addEventListener("fetch", event => {
  event.respondWith(handleRequest(event.request));
});
    
function checkSite(url) {
  return new URL(url).pathname.split('/')[1]; // we're checking the URL path, e.g. domain.com/something/else would yield something
}
    
async function handleRequest(request) {
  try {
    const path = new URL(request.url).pathname; // we need get the url in order to figure out where to route them
    switch (checkSite(request.url)) { 
      case 'de': // if the request is towards the de, e.g. domain.com/de/something
        request.url = 'https://sitehash0.stackpathcdn.com' + path;
      case 'fr': // if the request is towards the fr, e.g. domain.com/fr/something
        request.url = 'https://sitehash1.stackpathcdn.com' + path;
      case 'us': // if the request is towards the us, e.g. domain.com/us/something
        request.url = 'https://sitehash2.stackpathcdn.com' + path;
    }
    return fetch(request);
  } catch (e) {
    return new Response(e.stack || e, { status: 500 }); // error handling
  }
}

Access your script

You can access your script with any of the delivery domains on your account. 

Based on the above example, you can access the script with https://sitehash.stackpathcdn.com/de/index, and then the request will be sent to https://sitehash0.stackpathcdn.com/de/index.