I'm new to the Shopify App Platform and checking out how to use it and got stuck. Please help out if you know the answer.
I am creating an app to show a popup on the store and collect user's email address and display it in an embedded app. I am using the `ScriptTag` to show the modal and can write some code to hit a `POST` API. I read on the community that the API route must be there in my app's `server.js` file from where I can connect to my MongoDB instance to save it. Can you please share how to do it along with some code snippet which shows the same. Also, how do i authenticate the API request to make sure that the request is coming from the submitted modal and not some person hitting it via an API client or script?