Rails: How to disable app after certain amount of usage - ruby-on-rails

Question

I have a Rails/Shopify app that processes orders from the User's Shopify store. I want to have tiered plans (e.g. Bronze < 20 orders, Silver < 100 orders, Gold 100+).
What's the best way to implement this?
1) How do I track which subscription plan they are on, when it changes etc?
2) How do I disable the app once a user hits their limit?
Any links to articles/tutorials/gems to help would be great.

Answer 1

I would do it the following way. Once you have the token you can access the application charges for the shop you're in. You could either use
GET /admin/recurring_application_charges/455696195.json
or like I use it
ShopifyAPI::RecurringApplicationCharges.current
which gets you the current plan the user is on. You can access the name of the plan etc. To track how many orders were processed I would write a controller and implement a simple counter. Each time a request is being sent the counter is incremented. Once the limit is reached you can redirect him to an error page or somewhere else.
To answer the second part of your question you could access the current charge as mentioned above and get all the information you need (e.g. "billing_on": "2015-03-27T00:00:00+00:00")
Here is a sample response with all the available fields:
HTTP/1.1 200 OK
{
"recurring_application_charge": {
"activated_on": null,
"api_client_id": 755357713,
"billing_on": "2015-03-27T00:00:00+00:00",
"cancelled_on": null,
"created_at": "2015-03-28T13:31:19-04:00",
"id": 455696195,
"name": "Super Mega Plan",
"price": "15.00",
"return_url": "http:\/\/yourapp.com",
"status": "pending",
"test": null,
"trial_days": 0,
"trial_ends_on": null,
"updated_at": "2015-03-28T13:31:19-04:00",
"decorated_return_url": "http:\/\/yourapp.com?charge_id=455696195",
"confirmation_url": "https:\/\/apple.myshopify.com\/admin\/charges\/455696195\/confirm_recurring_application_charge?signature=BAhpBENfKRs%3D--a911ece9470850c96f6c7735c684b8a3f6869594"
}
}
You can find more under https://docs.shopify.com/api/recurringapplicationcharge or https://docs.shopify.com/api/applicationcharge
Hope I could help