Communicate with a server

Often, an extension running on a simulator or a device will need to communicate with a development server running on a local machine. One solution is to use the session API to get session tokens, and to pass these tokens to your development servers for authentication using the shopify_app gem.

Requests originating from an extension will be of origin cdn.shopify.com. Your server needs to allow requests from this origin.

Shopify POS will refuse to fetch any non-HTTPS requests. Therefore, you must find a way to host your development server where it serves HTTPS requests. For example, a standard rails server will run on localhost:3000. Attempting to access this server from an Android emulator using 10.0.2.2:3000 will fail. One strategy is to use Cloudflare Quick Tunnels, which provide an HTTPS URL to connect.

Below is an example extension that presents a Smart Grid tile. When tapped, the tile will present a modal that uses the Session API to get a session token, and then fetches a test endpoint on the development server.