handle percent coupons w/ stripe subscriptions

CHANGELOG.md

@@ -4,6 +4,7 @@
 - Refactored theme builder to use scss files
 - Updated stripe gem to 5.21.0
 - Architecture documentation
+- Improved coupon creation/deletion workflow
 - Fix a bug: unable to access embedded plan views
 - Fix a bug: warning message overflow in credit wallet modal
 - Fix a bug: when using a cash coupon, the amount shown in the statistics is invalid

app/models/coupon.rb

@@ -5,7 +5,7 @@ class Coupon < ApplicationRecord
   has_many :invoices
   has_many :payment_schedule
 
-  after_commit :create_stripe_coupon, on: [:create]
+  after_save :create_stripe_coupon, on: [:create]
   after_commit :delete_stripe_coupon, on: [:destroy]
 
   validates :name, presence: true
@@ -94,7 +94,7 @@ class Coupon < ApplicationRecord
   private
 
   def create_stripe_coupon
-    StripeWorker.perform_async(:create_stripe_coupon, id)
+    StripeService.create_stripe_coupon(id)
   end
 
   def delete_stripe_coupon

app/models/payment_schedule.rb

@@ -52,7 +52,7 @@ class PaymentSchedule < PaymentDocument
   def post_save(setup_intent_id)
     return unless payment_method == 'stripe'
 
-    StripeService.create_stripe_subscription(id, setup_intent_id)
+    StripeService.create_stripe_subscription(self, setup_intent_id)
   end
 
   private

app/models/reservation.rb

@@ -45,9 +45,7 @@ class Reservation < ApplicationRecord
   def generate_subscription
     return unless plan_id
 
-    self.subscription = Subscription.find_or_initialize_by(statistic_profile_id: statistic_profile_id)
+    self.subscription = Subscription.new(plan_id: plan_id, statistic_profile_id: statistic_profile_id, expiration_date: nil)
-    subscription.attributes = { plan_id: plan_id, statistic_profile_id: statistic_profile_id, expiration_date: nil }
-
     subscription.init_save
     subscription
   end

app/services/payment_schedule_service.rb

@@ -20,8 +20,8 @@ class PaymentScheduleService
     ps = PaymentSchedule.new(scheduled: plan, total: price + other_items, coupon: coupon)
     deadlines = plan.duration / 1.month
     per_month = (price / deadlines).truncate
-    adjustment = if per_month * deadlines != price
+    adjustment = if per_month * deadlines + other_items.truncate != ps.total
-                   price - (per_month * deadlines)
+                   ps.total - (per_month * deadlines + other_items.truncate)
                  else
                    0
                  end
@@ -30,9 +30,9 @@ class PaymentScheduleService
       date = DateTime.current + i.months
       details = { recurring: per_month }
       amount = if i.zero?
-                 details[:adjustment] = adjustment
+                 details[:adjustment] = adjustment.truncate
-                 details[:other_items] = other_items
+                 details[:other_items] = other_items.truncate
-                 per_month + adjustment + other_items
+                 per_month + adjustment.truncate + other_items.truncate
                else
                  per_month
                end
@@ -48,7 +48,7 @@ class PaymentScheduleService
 
   def create(subscription, total, coupon: nil, operator: nil, payment_method: nil, reservation: nil, user: nil, setup_intent_id: nil)
     subscription = reservation.generate_subscription if !subscription && reservation&.plan_id
-    raise InvalidSubscriptionError unless subscription
+    raise InvalidSubscriptionError unless subscription&.persisted?
 
     schedule = compute(subscription.plan, total, coupon)
     ps = schedule[:payment_schedule]

app/services/reservations/reserve.rb

@@ -25,16 +25,16 @@ class Reservations::Reserve
                                     operator_profile_id: operator_profile_id,
                                     user: user,
                                     payment_method: payment_method,
-                                    coupon_code: payment_details[:coupon],
+                                    coupon: payment_details[:coupon],
                                     setup_intent_id: intent_id)
                 else
                   generate_invoice(reservation, operator_profile_id, payment_details, intent_id)
                 end
       WalletService.debit_user_wallet(payment, user, reservation)
-      payment.save
       reservation.save
-      payment.post_save(intent_id)
       reservation.post_save
+      payment.save
+      payment.post_save(intent_id)
     end
     true
   end
@@ -44,10 +44,9 @@ class Reservations::Reserve
   ##
   # Generate the invoice for the given reservation+subscription
   ##
-  def generate_schedule(reservation: nil, total: nil, operator_profile_id: nil, user: nil, payment_method: nil, coupon_code: nil,
+  def generate_schedule(reservation: nil, total: nil, operator_profile_id: nil, user: nil, payment_method: nil, coupon: nil,
                         setup_intent_id: nil)
     operator = InvoicingProfile.find(operator_profile_id)&.user
-    coupon = Coupon.find_by(code: coupon_code) unless coupon_code.nil?
 
     PaymentScheduleService.new.create(
       nil,

app/services/stripe_service.rb

@@ -5,9 +5,8 @@ class StripeService
   class << self
 
     # Create the provided PaymentSchedule on Stripe, using the Subscription API
-    def create_stripe_subscription(payment_schedule_id, setup_intent_id)
+    def create_stripe_subscription(payment_schedule, setup_intent_id)
       stripe_key = Setting.get('stripe_secret_key')
-      payment_schedule = PaymentSchedule.find(payment_schedule_id)
       first_item = payment_schedule.ordered_items.first
 
       case payment_schedule.scheduled_type
@@ -35,8 +34,8 @@ class StripeService
       stp_subscription = Stripe::Subscription.create({
                                                        customer: payment_schedule.invoicing_profile.user.stp_customer_id,
                                                        cancel_at: subscription.expiration_date.to_i,
-                                                       promotion_code: payment_schedule.coupon&.code,
                                                        add_invoice_items: items,
+                                                       coupon: payment_schedule.coupon&.code,
                                                        items: [
                                                          { price: price[:id] }
                                                        ],
@@ -45,6 +44,25 @@ class StripeService
       payment_schedule.update_attributes(stp_subscription_id: stp_subscription.id)
     end
 
+    def create_stripe_coupon(coupon_id)
+      coupon = Coupon.find(coupon_id)
+      stp_coupon = {
+        id: coupon.code,
+        duration: coupon.validity_per_user
+      }
+      if coupon.type == 'percent_off'
+        stp_coupon[:percent_off] = coupon.percent_off
+      elsif coupon.type == 'amount_off'
+        stp_coupon[:amount_off] = coupon.amount_off
+        stp_coupon[:currency] = Setting.get('stripe_currency')
+      end
+
+      stp_coupon[:redeem_by] = coupon.valid_until.to_i unless coupon.valid_until.nil?
+      stp_coupon[:max_redemptions] = coupon.max_usages unless coupon.max_usages.nil?
+
+      Stripe::Coupon.create(stp_coupon, api_key: Setting.get('stripe_secret_key'))
+    end
+
     private
 
     def subscription_invoice_items(payment_schedule, subscription, first_item, reservable_stp_id)

app/services/subscriptions/subscribe.rb

@@ -24,13 +24,15 @@ class Subscriptions::Subscribe
 
     ActiveRecord::Base.transaction do
       subscription.init_save
+      raise InvalidSubscriptionError unless subscription&.persisted?
+
       payment = if schedule
                   generate_schedule(subscription: subscription,
                                     total: payment_details[:before_coupon],
                                     operator_profile_id: operator_profile_id,
                                     user: user,
                                     payment_method: payment_method,
-                                    coupon_code: payment_details[:coupon],
+                                    coupon: payment_details[:coupon],
                                     setup_intent_id: intent_id)
                 else
                   generate_invoice(subscription, operator_profile_id, payment_details, intent_id)
@@ -75,10 +77,9 @@ class Subscriptions::Subscribe
   ##
   # Generate the invoice for the given subscription
   ##
-  def generate_schedule(subscription: nil, total: nil, operator_profile_id: nil, user: nil, payment_method: nil, coupon_code: nil,
+  def generate_schedule(subscription: nil, total: nil, operator_profile_id: nil, user: nil, payment_method: nil, coupon: nil,
                         setup_intent_id: nil)
     operator = InvoicingProfile.find(operator_profile_id)&.user
-    coupon = Coupon.find_by(code: coupon_code) unless coupon_code.nil?
 
     PaymentScheduleService.new.create(
       subscription,

app/workers/stripe_worker.rb

@@ -21,28 +21,11 @@ class StripeWorker
     user.update_columns(stp_customer_id: customer.id)
   end
 
-  def create_stripe_coupon(coupon_id)
-    coupon = Coupon.find(coupon_id)
-    stp_coupon = {
-      id: coupon.code,
-      duration: coupon.validity_per_user
-    }
-    if coupon.type == 'percent_off'
-      stp_coupon[:percent_off] = coupon.percent_off
-    elsif coupon.type == 'amount_off'
-      stp_coupon[:amount_off] = coupon.amount_off
-      stp_coupon[:currency] = Setting.get('stripe_currency')
-    end
-
-    stp_coupon[:redeem_by] = coupon.valid_until.to_i unless coupon.valid_until.nil?
-    stp_coupon[:max_redemptions] = coupon.max_usages unless coupon.max_usages.nil?
-
-    Stripe::Coupon.create(stp_coupon, api_key: Setting.get('stripe_secret_key'))
-  end
-
   def delete_stripe_coupon(coupon_code)
     cpn = Stripe::Coupon.retrieve(coupon_code, api_key: Setting.get('stripe_secret_key'))
     cpn.delete
+  rescue Stripe::InvalidRequestError => e
+    STDERR.puts "WARNING: Unable to delete the coupon on Stripe: #{e}"
   end
 
   def create_or_update_stp_product(class_name, id)