I hope I'm on the right track with what you're aiming to achieve here. From what I gather (pieced together from this and your previous question), it seems like you want something in the browser that, when clicked, retrieves status information from an external API and displays it in the client.
Based on this assumption, my recommendation would be to define your desired function as triggered by an HTTP request to the Express server. The server can then run the function and send whatever data you need back to the client.
In your Express server definition (assuming your Express variable is app):
app.get('/request', someFunction);
In the someFunction, outline the actions you want to take, how they relate to the request and response, and what should be sent back to the client. While Express expects the function to receive request and response as arguments, you may not necessarily have to use them:
someFunction(req,res) {
// do the required actions with aws or any other service
res.send(foo); // where foo can be JSON, text, or any other data for the client to manipulate
}
On the client side, you would have a function bound to onclick that sends a request to the /request endpoint. This function could utilize AJAX or even load a different page entirely.
This setup ensures that display and behavior are handled on the client side, while data retrieval and manipulation are managed by the server. It also eliminates concerns about require() statements on the client-side (although possible through tools like Browserify, they are not necessary and can add unnecessary complexity to the code).