Add Stripe-based billing system

Author: jorgemanrubia

app/assets/stylesheets/fizzy/saas.css

@@ -0,0 +1,64 @@
+/* Subscriptions
+/* ------------------------------------------------------------------------ */
+:root {
+  --settings-subscription-background: linear-gradient(to bottom, var(--color-canvas), oklch(var(--lch-violet-lighter)));
+  --settings-subscription-color: oklch(var(--lch-violet-medium));
+  --settings-subscription-text-color: oklch(var(--lch-violet-dark));
+
+  .settings-subscription__button {
+    --btn-background: var(--settings-subscription-color);
+    --btn-border-color: var(--color-canvas);
+    --btn-color: var(--color-canvas);
+    --focus-ring-color: var(--color-ink);
+  }
+
+  .settings-subscription__divider {
+    --divider-color: currentColor;
+
+    color: var(--settings-subscription-color);
+    margin-block-start: calc(var(--block-space-half) * -1);
+  }
+
+  .settings-subscription__footer {
+    color: var(--settings-subscription-text-color);
+
+    &::before {
+      content: "————";
+      display: block;
+      margin: auto;
+      text-align: center;
+    }
+  }
+
+  .settings-subscription__notch {
+    animation: wiggle 500ms ease;
+    background: var(--settings-subscription-background);
+    box-shadow: 0 0 0.3em 0.2em var(--settings-subscription-color);
+    border-radius: 3em;
+    color: var(--settings-subscription-text-color);
+    margin-inline: auto;
+    padding: 0 0.3em 0 1.2em;
+    transform: rotate(-1deg);
+
+    @media (max-width: 640px) {
+      padding-block: 0.6em;
+      padding-inline-start: 0.3em;
+    }
+
+    .btn {
+      margin-block: 0.3em;
+    }
+  }
+
+  .settings-subscription__panel {
+    background: var(--settings-subscription-background);
+  }
+
+  .settings_subscription__warning {
+    color: var(--settings-subscription-text-color);
+
+    a {
+      color: var(--settings-subscription-text-color);
+    }
+  }
+}

app/assets/stylesheets/fizzy/saas/application.css

@@ -0,0 +1,19 @@
+class Account::BillingPortalsController < ApplicationController
+  before_action :ensure_admin
+  before_action :ensure_subscribed_account
+
+  def show
+    redirect_to create_stripe_billing_portal_session.url, allow_other_host: true
+  end
+
+  private
+    def ensure_subscribed_account
+      unless Current.account.subscribed?
+        redirect_to account_subscription_path, alert: "No billing information found"
+      end
+    end
+
+    def create_stripe_billing_portal_session
+      Stripe::BillingPortal::Session.create(customer: Current.account.subscription.stripe_customer_id, return_url: account_settings_url)
+    end
+end

app/controllers/account/billing_portals_controller.rb

@@ -0,0 +1,38 @@
+class Account::SubscriptionsController < ApplicationController
+  before_action :ensure_admin
+  before_action :set_stripe_session, only: :show
+
+  def show
+  end
+
+  def create
+    session = Stripe::Checkout::Session.create \
+      customer: find_or_create_stripe_customer,
+      mode: "subscription",
+      line_items: [ { price: Plan.paid.stripe_price_id, quantity: 1 } ],
+      success_url: account_subscription_url + "?session_id={CHECKOUT_SESSION_ID}",
+      cancel_url: account_subscription_url,
+      metadata: { account_id: Current.account.id, plan_key: Plan.paid.key }
+
+    redirect_to session.url, allow_other_host: true
+  end
+
+  private
+    def set_stripe_session
+      @session = Stripe::Checkout::Session.retrieve(params[:session_id]) if params[:session_id]
+    end
+
+    def find_or_create_stripe_customer
+      find_stripe_customer || create_stripe_customer
+    end
+
+    def find_stripe_customer
+      Stripe::Customer.retrieve(Current.account.subscription.stripe_customer_id) if Current.account.subscription&.stripe_customer_id
+    end
+
+    def create_stripe_customer
+      Stripe::Customer.create(email: Current.user.identity.email_address, name: Current.account.name, metadata: { account_id: Current.account.id }).tap do |customer|
+        Current.account.create_subscription!(stripe_customer_id: customer.id, plan_key: Plan.paid.key, status: "incomplete")
+      end
+    end
+end

app/controllers/account/subscriptions_controller.rb

@@ -0,0 +1,5 @@
+class Admin::AccountSearchesController < AdminController
+  def create
+    redirect_to saas.edit_admin_account_path(params[:q])
+  end
+end

app/controllers/admin/account_searches_controller.rb

@@ -0,0 +1,25 @@
+class Admin::AccountsController < AdminController
+  layout "public"
+
+  before_action :set_account, only: %i[ edit update ]
+
+  def index
+  end
+
+  def edit
+  end
+
+  def update
+    @account.update!(account_params)
+    redirect_to saas.edit_admin_account_path(@account.external_account_id), notice: "Account updated"
+  end
+
+  private
+    def set_account
+      @account = Account.find_by!(external_account_id: params[:id])
+    end
+
+    def account_params
+      params.expect(account: [ :cards_count ])
+    end
+end

app/controllers/admin/accounts_controller.rb

@@ -0,0 +1,20 @@
+class Admin::StatsController < AdminController
+  layout "public"
+
+  def show
+    @accounts_total = Account.count
+    @accounts_last_7_days = Account.where(created_at: 7.days.ago..).count
+    @accounts_last_24_hours = Account.where(created_at: 24.hours.ago..).count
+
+    @identities_total = Identity.count
+    @identities_last_7_days = Identity.where(created_at: 7.days.ago..).count
+    @identities_last_24_hours = Identity.where(created_at: 24.hours.ago..).count
+
+    @top_accounts = Account
+      .where("cards_count > 0")
+      .order(cards_count: :desc)
+      .limit(20)
+
+    @recent_accounts = Account.order(created_at: :desc).limit(10)
+  end
+end

app/controllers/admin/stats_controller.rb

@@ -0,0 +1,12 @@
+module Card::Limited
+  extend ActiveSupport::Concern
+
+  included do
+    before_action :ensure_can_create_cards, only: %i[ create ]
+  end
+
+  private
+    def ensure_can_create_cards
+      head :forbidden if Current.account.exceeding_card_limit?
+    end
+end

app/controllers/concerns/card/limited.rb

@@ -0,0 +1,83 @@
+class Stripe::WebhooksController < ApplicationController
+  allow_unauthenticated_access
+  skip_before_action :require_account
+  skip_before_action :verify_authenticity_token
+
+  def create
+    event = verify_webhook_signature
+    return head :bad_request unless event
+
+    dispatch_stripe_event(event)
+
+    head :ok
+  end
+
+  private
+    def dispatch_stripe_event(event)
+      case event.type
+        when "checkout.session.completed"
+          handle_checkout_completed(event.data.object)
+        when "customer.subscription.updated"
+          handle_subscription_updated(event.data.object)
+        when "customer.subscription.deleted"
+          handle_subscription_deleted(event.data.object)
+        when "invoice.payment_failed"
+          handle_payment_failed(event.data.object)
+      end
+    end
+
+    def verify_webhook_signature
+      payload = request.body.read
+      sig_header = request.env["HTTP_STRIPE_SIGNATURE"]
+
+      Stripe::Webhook.construct_event(payload, sig_header, ENV["STRIPE_WEBHOOK_SECRET"])
+    rescue Stripe::SignatureVerificationError => e
+      Rails.logger.error "Stripe webhook signature verification failed: #{e.message}"
+      nil
+    end
+
+    def handle_checkout_completed(session)
+      return unless session.mode == "subscription"
+
+      subscription = find_subscription_by_customer(session.customer)
+      return unless subscription
+
+      stripe_subscription = Stripe::Subscription.retrieve(session.subscription)
+
+      subscription.update! \
+        stripe_subscription_id: stripe_subscription.id,
+        plan_key: session.metadata["plan_key"],
+        status: stripe_subscription.status,
+        current_period_end: extract_current_period_end(stripe_subscription)
+    end
+
+    def handle_subscription_updated(stripe_subscription)
+      if subscription = find_subscription_by_customer(stripe_subscription.customer)
+        subscription.update! \
+          status: stripe_subscription.status,
+          current_period_end: extract_current_period_end(stripe_subscription),
+          cancel_at: stripe_subscription.cancel_at ? Time.at(stripe_subscription.cancel_at) : nil
+      end
+    end
+
+    def handle_subscription_deleted(stripe_subscription)
+      if subscription = find_subscription_by_customer(stripe_subscription.customer)
+        subscription.update!(status: "canceled", stripe_subscription_id: nil)
+      end
+    end
+
+    def handle_payment_failed(invoice)
+      if subscription = find_subscription_by_customer(invoice.customer)
+        subscription.update!(status: "past_due")
+      end
+    end
+
+    def find_subscription_by_customer(customer_id)
+      Account::Subscription.find_by(stripe_customer_id: customer_id)
+    end
+
+    def extract_current_period_end(stripe_subscription)
+      timestamp = stripe_subscription.items.data.first&.current_period_end
+      Time.at(timestamp) if timestamp
+    end
+end

app/controllers/stripe/webhooks_controller.rb

@@ -0,0 +1,11 @@
+module SubscriptionsHelper
+  def subscription_period_end_action(subscription)
+    if subscription.to_be_canceled?
+      "Your Fizzy subscription ends on"
+    elsif subscription.canceled?
+      "Your Fizzy subscription ended on"
+    else
+      "Your next payment of <b>$#{ subscription.plan.price }</b> will be billed on".html_safe
+    end
+  end
+end