FEATURE: Cancel payments at end of subscription vs immediately

Previously, when a user canceled a subscription, the access would revoke
immediately on Discourse vs. at the end of the billing period. This
commit changes the behavior to remove membership at the end of the
billing period using Stripe's `cancel_at_period_end` attribute on the
Subscription object.

This commit now requires the setup of webhooks for subscription
processing to occur correctly.

app/controllers/discourse_subscriptions/hooks_controller.rb

@@ -3,6 +3,10 @@
 module DiscourseSubscriptions
   class HooksController < ::ApplicationController
     include DiscourseSubscriptions::Group
+    include DiscourseSubscriptions::Stripe
+    layout false
+    skip_before_action :check_xhr
+    skip_before_action :redirect_to_login_if_required
     skip_before_action :verify_authenticity_token, only: [:create]
 
     def create
@@ -15,7 +19,7 @@ module DiscourseSubscriptions
       rescue JSON::ParserError => e
         render_json_error e.message
         return
-      rescue Stripe::SignatureVerificationError => e
+      rescue ::Stripe::SignatureVerificationError => e
         render_json_error e.message
         return
       end
@@ -34,19 +38,7 @@ module DiscourseSubscriptions
         end
 
       when 'customer.subscription.deleted'
-
-        customer = Customer.find_by(
-          customer_id: event[:data][:object][:customer],
-          product_id: event[:data][:object][:plan][:product]
-        )
-
-        if customer
-          customer.delete
-
-          user = ::User.find(customer.user_id)
-          group = plan_group(event[:data][:object][:plan])
-          group.remove(user) if group
-        end
+        delete_subscription(event)
       end
 
       head 200
@@ -59,11 +51,32 @@ module DiscourseSubscriptions
     end
 
     def subscription_complete?(event)
-      event.dig(:data, :object, :status) == 'complete'
+      event && event[:data] && event[:data][:object] && event[:data][:object][:status] && event[:data][:object][:status] == 'complete'
     end
 
     def previously_incomplete?(event)
-      event.dig(:data, :previous_attributes, :status) == 'incomplete'
+      event && event[:data] && event[:data][:previous_attributes] && event[:data][:previous_attributes][:status] && event[:data][:previous_attributes][:status] == 'incomplete'
+    end
+
+    def delete_subscription(event)
+      customer = Customer.find_by(
+        customer_id: event[:data][:object][:customer],
+        product_id: event[:data][:object][:plan][:product]
+      )
+
+      if customer
+        sub_model = Subscription.find_by(
+          customer_id: customer.id,
+          external_id: [:id]
+        )
+
+        sub_model.delete if sub_model
+
+        user = ::User.find(customer.user_id)
+        customer.delete
+        group = plan_group(event[:data][:object][:plan])
+        group.remove(user) if group
+      end
     end
   end
 end

app/controllers/discourse_subscriptions/user/subscriptions_controller.rb

@@ -48,30 +48,13 @@ module DiscourseSubscriptions
       end
 
       def destroy
+        # we cancel but don't remove until the end of the period
+        # full removal is done via webhooks
         begin
-          subscription = ::Stripe::Subscription.retrieve(params[:id])
+          subscription = ::Stripe::Subscription.update(params[:id], { cancel_at_period_end: true, } )
 
-          customer = Customer.find_by(
-            user_id: current_user.id,
-            customer_id: subscription[:customer],
-            product_id: subscription[:plan][:product]
-          )
-
-          if customer.present?
-            sub_model = Subscription.find_by(
-              customer_id: customer.id,
-              external_id: params[:id]
-            )
-
-            deleted = ::Stripe::Subscription.delete(params[:id])
-            customer.delete
-
-            sub_model.delete if sub_model
-
-            group = plan_group(subscription[:plan])
-            group.remove(current_user) if group
-
-            render_json_dump deleted
+          if subscription
+            render_json_dump subscription
           else
             render_json_error I18n.t('discourse_subscriptions.customer_not_found')
           end

assets/javascripts/discourse/routes/user-billing-subscriptions.js.es6

@@ -29,6 +29,7 @@ export default Route.extend({
               )
               .finally(() => {
                 subscription.set("loading", false);
+                this.refresh();
               });
           }
         }

assets/javascripts/discourse/templates/user/billing/subscriptions.hbs

@@ -19,7 +19,7 @@
           {{#if subscription.loading}}
             {{loading-spinner size="small"}}
           {{else}}
-            {{d-button disabled=subscription.canceled label="cancel" action=(route-action "cancelSubscription" subscription) icon="times"}}
+            {{d-button disabled=subscription.canceled_at label="discourse_subscriptions.user.subscriptions.cancelled" action=(route-action "cancelSubscription" subscription) icon="times"}}
           {{/if}}
         </td>
       </tr>

config/locales/client.en.yml

@@ -51,6 +51,7 @@ en:
           id: Subscription ID
           status: Status
           created_at: Created
+          cancelled: cancelled
           operations:
             destroy:
               confirm: Are you sure you want to cancel this subscription?

config/routes.rb

@@ -19,13 +19,13 @@ DiscourseSubscriptions::Engine.routes.draw do
   end
 
   resources :customers, only: [:create]
-  resources :hooks, only: [:create]
   resources :plans, only: [:index], constraints: SubscriptionsUserConstraint.new
   resources :products, only: [:index, :show]
   resources :subscriptions, only: [:create]
 
   post '/subscriptions/finalize' => 'subscriptions#finalize'
 
+  post '/hooks' => 'hooks#create'
   get '/' => 'subscriptions#index', constraints: SubscriptionsUserConstraint.new
   get '/:id' => 'subscriptions#index', constraints: SubscriptionsUserConstraint.new
 end

spec/requests/user/subscriptions_controller_spec.rb

@@ -82,153 +82,6 @@ module DiscourseSubscriptions
           )
         end
       end
-
-      describe "delete" do
-        let(:group) { Fabricate(:group, name: 'subscribers') }
-
-        before do
-          # Users can have more than one customer id
-          Customer.create(user_id: user.id, customer_id: 'customer_id_1', product_id: 'p_1')
-          Customer.create(user_id: user.id, customer_id: 'customer_id_1', product_id: 'p_2')
-          Customer.create(user_id: user.id, customer_id: 'customer_id_2', product_id: 'p_2')
-
-          group.add(user)
-        end
-
-        it "does not delete a subscription when the customer is wrong" do
-          ::Stripe::Subscription
-            .expects(:retrieve)
-            .with('sub_12345')
-            .returns(
-              plan: { product: 'p_1' },
-              customer: 'wrong_id'
-            )
-
-          ::Stripe::Subscription
-            .expects(:delete)
-            .never
-
-          expect {
-            delete "/s/user/subscriptions/sub_12345.json"
-          }.not_to change { DiscourseSubscriptions::Customer.count }
-
-          expect(response.status).to eq 422
-        end
-
-        it "does not deletes the subscription when the product is wrong" do
-          ::Stripe::Subscription
-            .expects(:retrieve)
-            .with('sub_12345')
-            .returns(
-              plan: { product: 'p_wrong' },
-              customer: 'customer_id_2'
-            )
-
-          ::Stripe::Subscription
-            .expects(:delete)
-            .never
-
-          expect {
-            delete "/s/user/subscriptions/sub_12345.json"
-          }.not_to change { DiscourseSubscriptions::Customer.count }
-
-          expect(response.status).to eq 422
-        end
-
-        it "removes the user from the group" do
-          ::Stripe::Subscription
-            .expects(:retrieve)
-            .with('sub_12345')
-            .returns(
-              plan: { product: 'p_1', metadata: { group_name: 'subscribers' } },
-              customer: 'customer_id_1'
-            )
-
-          ::Stripe::Subscription
-            .expects(:delete)
-
-          expect {
-            delete "/s/user/subscriptions/sub_12345.json"
-          }.to change { user.groups.count }.by(-1)
-        end
-
-        it "does not remove the user from the group" do
-          ::Stripe::Subscription
-            .expects(:retrieve)
-            .with('sub_12345')
-            .returns(
-              plan: { product: 'p_1', metadata: { group_name: 'does_not_exist' } },
-              customer: 'customer_id_1'
-            )
-
-          ::Stripe::Subscription
-            .expects(:delete)
-
-          expect {
-            delete "/s/user/subscriptions/sub_12345.json"
-          }.not_to change { user.groups.count }
-        end
-
-        it "deletes the first subscription product 1" do
-          ::Stripe::Subscription
-            .expects(:retrieve)
-            .with('sub_12345')
-            .returns(
-              plan: { product: 'p_1', metadata: {} },
-              customer: 'customer_id_1'
-            )
-
-          ::Stripe::Subscription
-            .expects(:delete)
-            .with('sub_12345')
-
-          expect {
-            delete "/s/user/subscriptions/sub_12345.json"
-          }.to change { DiscourseSubscriptions::Customer.count }.by(-1)
-
-          expect(response.status).to eq 200
-        end
-
-        it "deletes the first subscription product 2" do
-          ::Stripe::Subscription
-            .expects(:retrieve)
-            .with('sub_12345')
-            .returns(
-              plan: { product: 'p_2', metadata: {} },
-              customer: 'customer_id_1'
-            )
-
-          ::Stripe::Subscription
-            .expects(:delete)
-            .with('sub_12345')
-
-          expect {
-            delete "/s/user/subscriptions/sub_12345.json"
-          }.to change { DiscourseSubscriptions::Customer.count }.by(-1)
-
-          expect(response.status).to eq 200
-        end
-
-        it "deletes the second subscription" do
-          ::Stripe::Subscription
-            .expects(:retrieve)
-            .with('sub_12345')
-            .returns(
-              plan: { product: 'p_2', metadata: {} },
-              customer: 'customer_id_2'
-            )
-
-          ::Stripe::Subscription
-            .expects(:delete)
-            .with('sub_12345')
-
-          expect {
-            delete "/s/user/subscriptions/sub_12345.json"
-          }.to change { DiscourseSubscriptions::Customer.count }.by(-1)
-
-          expect(response.status).to eq 200
-        end
-      end
     end
   end
 end