DEV: Add pagination to plans request (#272)

When pulling up a users subscriptions a 500 might occur if we don't find
their plan. If your account happens to have over 100 plans this can be
the cause of the 500 error. This change adds pagination when fetching
plans form stripe, so that we fetch them all.

https://meta.discourse.org/t/problem-with-500-error-with-subscriptions/360808?u=blake

app/controllers/discourse_subscriptions/user/subscriptions_controller.rb

@@ -24,7 +24,14 @@ module DiscourseSubscriptions
           subscriptions = []
 
           if subscription_ids
-            plans = ::Stripe::Price.list(expand: ["data.product"], limit: 100)
+            prices = []
+            price_params = { limit: 100, expand: ["data.product"] }
+            loop do
+              response = ::Stripe::Price.list(price_params)
+              prices.concat(response[:data])
+              break unless response[:has_more]
+              price_params[:starting_after] = response[:data].last.id
+            end
             all_subscriptions = []
 
             stripe_customer_ids.each do |stripe_customer_id|
@@ -35,7 +42,7 @@ module DiscourseSubscriptions
 
             subscriptions = all_subscriptions.select { |sub| subscription_ids.include?(sub[:id]) }
             subscriptions.map! do |subscription|
-              plan = plans[:data].find { |p| p[:id] == subscription[:items][:data][0][:price][:id] }
+              plan = prices.find { |p| p[:id] == subscription[:items][:data][0][:price][:id] }
               subscription.to_h.except!(:plan)
               subscription.to_h.merge(plan: plan, product: plan[:product].to_h.slice(:id, :name))
             end

spec/requests/user/subscriptions_controller_spec.rb

@@ -5,6 +5,14 @@ require "rails_helper"
 RSpec.describe DiscourseSubscriptions::User::SubscriptionsController do
   before { SiteSetting.discourse_subscriptions_enabled = true }
 
+  def create_price(id, product)
+    price = { id: id, product: product }
+    def price.id
+      self[:id]
+    end
+    price
+  end
+
   it "is a subclass of ApplicationController" do
     expect(DiscourseSubscriptions::User::SubscriptionsController < ::ApplicationController).to eq(
       true,
@@ -80,6 +88,42 @@ RSpec.describe DiscourseSubscriptions::User::SubscriptionsController do
         expect(subscription[:items][:data][0][:plan][:id]).to eq("price_1OrmlvEYXaQnncShNahrpKvA")
         expect(subscription[:product][:name]).to eq("Exclusive Access")
       end
+
+      it "aggregates prices from multiple pages using pagination logic" do
+        subscription_data = { id: "sub_10z", items: { data: [{ price: { id: "price_200" } }] } }
+        ::Stripe::Subscription
+          .stubs(:list)
+          .with(customer: "cus_23456", status: "all")
+          .returns({ data: [subscription_data] })
+
+        # Build the first page of 100 prices that do NOT include the desired price.
+        prices_page_1 =
+          (1..100).map do |i|
+            create_price("price_#{i}", { id: "prod_dummy", name: "Dummy Product #{i}" })
+          end
+
+        # Second page containing the desired price.
+        prices_page_2 = [create_price("price_200", { id: "prod_200", name: "Matching Product" })]
+
+        ::Stripe::Price
+          .expects(:list)
+          .with(has_entries(limit: 100, expand: ["data.product"]))
+          .returns({ data: prices_page_1, has_more: true })
+
+        ::Stripe::Price
+          .expects(:list)
+          .with(has_entries(limit: 100, expand: ["data.product"], starting_after: "price_100"))
+          .returns({ data: prices_page_2, has_more: false })
+
+        get "/s/user/subscriptions.json"
+        result = JSON.parse(response.body, symbolize_names: true)
+        subscription = result.first
+
+        expect(subscription[:id]).to eq("sub_10z")
+        expect(subscription[:plan][:id]).to eq("price_200")
+        expect(subscription[:product][:id]).to eq("prod_200")
+        expect(subscription[:product][:name]).to eq("Matching Product")
+      end
     end
 
     describe "update" do