Provides the capability to override an news-projects script with a different script with settings defined in localStorage.

The script being overridden needs to import and use this library:

import { proxy } from '@abcnews/dev-proxy';

function init() {
  // The code that kicks off your script goes here.
}

proxy('project-name').then(init);

To put the override into effect localStorage needs to contain an entry with key proxy_<project-name> that contains the URL of the script to override with.

The proxy function returns a promise that will either:

• resolve successfully, indicating that the script initialisation should go ahead (i.e. the .then(init) part of the above implementation example), or
• be rejected, indicating that an alternative script has been successfully identified and added to the document and the init function should not be run.

For the proxy function to successfully identify a script to run instead a few criteria need to be met:

• The script importing the proxy function should not have a NODE_ENV of 'development' (this prevents infinite loops when this proxy function is used on a dev server.
• The script should not be running on a production URL.
• localStorage must contain an entry identifying a suitable replacement hosted on an ABC url (including localhost aliases that include abc.net.au).

As of version 1.2.0 pressing the key combination Alt-M when you're in an approprate dev or preview environment offers an easy way to set the appropriate localStorage values to proxy relevant scripts on the page.