Stripe::Rails: A Rails Engine for use with stripe.com

This gem can help your rails application integrate with Stripe in the following ways

• manage stripe configurations in a single place.
• makes stripe.js available from the asset pipeline.
• manage plans and coupons from within your app.
• painlessly receive and validate webhooks from stripe.

Installation

Add this line to your application's Gemfile:

gem 'stripe-rails'

If you are going to be using stripe.js to securely collect credit card information on the client, then you will need to add the stripe javascript tags into your template. stripe-rails provides a helper to make this easy:

<%= stripe_javascript_tag %>

or, you can render it as a partial:

<%= render :partial => 'stripe/js' %>

In both cases, stripe-rails will choose a version of stripe.js appropriate for your development environment and automatically configure it to use your publishable API key. By default it uses stripe-debug.js for your development environment and stripe.js for everything else, but you can manually configure it per environment.

config.stripe.debug_js = true  # use stripe-debug.js
config.stripe.debug_js = false # use stripe.js

By default the helper renders the v3 version of stripe.js. You can provide an alternate version to the helper to generate the appropriate tag:

<%= stripe_javascript_tag(:v2) %>

Setup your API keys.

You will need to configure your application to authenticate with stripe.com using your api key. There are two methods to do this, you can either set the environment variable STRIPE_SECRET_KEY:

export STRIPE_SECRET_KEY=sk_test_xxyyzz

or if you are on heroku:

heroku config:add STRIPE_SECRET_KEY=sk_test_xxyyzz

You can also set this value from inside ruby configuration code:

config.stripe.secret_key = "sk_test_xxyyzz"

In either case, it is recommended that you not check in this value into source control.

You can verify that your api is set up and functioning properly by running the following command:

rake stripe:verify

If you are going to be using stripe.js, then you will also need to set the value of your publishable key. A nice way to do it is to set your test publishable for all environments:

# config/application.rb
# ...
config.stripe.publishable_key = 'pk_test_XXXYYYZZZ'

And then override it to use your live key in production only

# config/environments/production.rb
# ...
config.stripe.publishable_key = 'pk_live_XXXYYYZZZ'

This key will be publicly visible on the internet, so it is ok to put in your source.

Manually set your API version (optional)

If you need to test a new API version in development, you can override the version number manually.

# config/environments/development.rb
# ...
config.stripe.api_version = '2015-10-16'

Setup your payment configuration

If you're using subscriptions, then you'll need to set up your application's payment plans and discounts. Stripe::Rails lets you automate the management of these definitions from within the application itself. To get started:

rails generate stripe:install

this will generate the configuration files containing your plan and coupon definitions:

create  config/stripe/products.rb
create  config/stripe/plans.rb
create  config/stripe/coupons.rb

Configuring your plans and coupons

Use the plan builder to define as many plans as you want in config/stripe/plans.rb

Stripe.plan :silver do |plan|
  plan.name = 'ACME Silver'
  plan.amount = 699 # $6.99
  plan.interval = 'month'
end

Stripe.plan :gold do |plan|
  plan.name = 'ACME Gold'
  plan.amount = 999 # $9.99
  plan.interval = 'month'
end

Stripe.plan :bronze do |plan|
  # Use an existing product id to prevent a new plan from
  # getting created
  plan.product_id = 'prod_XXXXXXXXXXXXXX'
  plan.amount = 999 # $9.99
  plan.interval = 'month'
end

This will define constants for these plans in the Stripe::Plans module so that you can refer to them by reference as opposed to an id string.

Stripe::Plans::SILVER # => 'silver: ACME Silver'
Stripe::Plans::GOLD # => 'gold: ACME Gold'

Coupons are created in much the same way:

Stripe.coupon :super_elite_free_vip do |coupon|
  coupon.duration = 'forever'
  coupon.percent_off = 100
  coupon.max_redemptions = 5
end

As are Products:

Stripe.product :primo do |product|
  product.name = 'PRIMO as a service'
  product.type = 'service'
  product.statement_descriptor = 'PRIMO'
end

To upload your plans and coupons onto stripe.com, run:

rake stripe:prepare

This will create any plans and coupons that do not currently exist, and treat as a NOOP any plans that do, so you can run this command safely as many times as you wish. Now you can use any of these plans in your application.

NOTE: You must destroy plans manually from your stripe dashboard.

Webhooks

Stripe::Rails automatically sets up your application to receive webhooks from stripe.com whenever a payment event is generated. To enable this, you will need to configure your stripe webhooks to point back to your application. By default, the webhook controller is mounted at '/stripe/events' so you would want to enter in http://myproductionapp.com/stripe/events as your url for live mode, and http://mystagingapp.com/stripe/events for your test mode.

If you want to mount the stripe engine somewhere else, you can do so by setting the stripe.endpoint parameter. E.g.

config.stripe.endpoint = '/payment/stripe-integration'

Your new webhook URL would then be http://myproductionapp/payment/stripe-integration/events

Signed Webhooks

Validation of your webhook's signature uses your webhook endpoint signing secret. Before you can verify signatures, you need to retrieve your endpoint’s secret your Stripe Dashboard. Select an endpoint for which you want to obtain the secret, then select the Click to reveal button.

# config/application.rb
# ...
config.stripe.signing_secret = 'whsec_XXXYYYZZZ'

Each secret is unique to the endpoint to which it corresponds. If you use multiple endpoints, you must obtain a secret for each one. After this setup, Stripe starts to sign each webhook it sends to the endpoint. Because of this, we recommend setting this variable with an environment variable:

export STRIPE_SIGNING_SECRET=whsec_XXXYYYZZZ

config.stripe.signing_secret = ENV.fetch('STRIPE_SIGNING_SECRET')

Testing Signed Webhooks Locally

In order to test signed webhooks, you'll need to trigger test webhooks from your Stripe dashboard, and configure your local environment to receive remote network requests. To do so, we recommend using ngrok to configure a secure tunnel to localhost.

Once configured and running, ngrok will give you a unique URL which can be used to set up a webhook endpoint. Webhook endpoints are configured in your Dashboard's Webhook settings section. Make sure you are in Test mode and click Add endpoint, and provide your ngrok URL along with the stripe.endpoint suffix.

An example webhook URL would then be https://bf2a5d21.ngrok.io/stripe/events.

Once your endpoint is configured, you can reveal the Signing secret. This will need to be set as documented above:

# config/application.rb
# ...
config.stripe.signing_secret = 'whsec_XXXYYYZZZ'

And you'll need to restart your rails server with:

rails restart

Now you're ready to click Send test webhook, and trigger whichever events you'd like to test from Stripe itself.

Disabling auto mount

Sometimes, you don't want the stripe engine to be auto-mounted so that you control exactly what priority it will take in your routing table. This is especially important if you have a catch-all route which should appear after all other routes. In order to disable auto-mounting of the Stripe engine:

# in application.rb
config.stripe.auto_mount = false

Then, you will have to manually mount the engine in your main application.

# in your application's routes.rb:
mount Stripe::Engine => "/stripe"

Responding to webhooks

Once you have your webhook URL configured you can respond to a stripe webhook anywhere in your application just by including the Stripe::Callbacks module into your class and declaring a callback with one of the callback methods. For example, to update a customer's payment status:

class User < ActiveRecord::Base
  include Stripe::Callbacks

  after_customer_updated! do |customer, event|
    user = User.find_by_stripe_customer_id(customer.id)
    if customer.delinquent
      user.is_account_current = false
      user.save!
    end
  end
end

or to send an email with one of your customer's monthly invoices

class InvoiceMailer < ActionMailer::Base
  include Stripe::Callbacks

  after_invoice_created! do |invoice, event|
    user = User.find_by_stripe_customer(invoice.customer)
    new_invoice(user, invoice).deliver
  end

  def new_invoice(user, invoice)
    @user = user
    @invoice = invoice
    mail :to => user.email, :subject => '[Acme.com] Your new invoice'
  end
end

Note: Stripe::Callbacks won't get included until the including class has been loaded. This is usually not an issue in the production environment as eager loading is enabled by default (config.eager_load = true). You may run into an issue in your development environment where eager loading is disabled by default.

If you don't wish to enable eager loading in development, you can configure the classes to be eager loaded like so

# in your application's config/environments/development.rb
config.stripe.eager_load = 'account', 'module/some_class', 'etc'

This will ensure that callbacks will get loaded in those configured classes if eager loading is disabled.

The naming convention for the callback events is after__{callback_name}! where callback_name is name of the stripe event with all . characters substituted with underscores. So, for example, the stripe event customer.discount.created can be hooked by after_customer_discount_created! and so on...

Each web hook is passed an instance of the stripe object to which the event corresponds (Stripe::Customer, Stripe::Invoice, Stripe::Charge, etc...) as well as the Stripe::Event which contains metadata about the event being raised.

By default, the event is re-fetched securely from stripe.com to prevent damage to your system by a malicious system spoofing real stripe events.

Critical and non-critical hooks

So far, the examples have all used critical hooks, but in fact, each callback method comes in two flavors: "critical", specified with a trailing ! character, and "non-critical", which has no "bang" character at all. What distinguishes one from the other is that if an exception is raised in a critical callback, it will cause the entire webhook to fail.

This will indicate to stripe.com that you did not receive the webhook at all, and that it should retry it again later until it receives a successful response. On the other hand, there are some tasks that are more tangential to the payment work flow and aren't such a big deal if they get dropped on the floor. For example, A non-critical hook can be used to do things like have a bot notify your company's chatroom that something a credit card was successfully charged:

class AcmeBot
  include Stripe::Callbacks

  after_charge_succeeded do |charge|
    announce "Attention all Dudes and Dudettes. Ya'll are so PAID!!!"
  end
end

Chances are that if you experience a momentary failure in connectivity to your chatroom, you don't want the whole payment notification to fail.

Filtering Callbacks

Certain stripe events represent updates to existing data. You may want to only fire the event when certain attributes of that data are updated. You can pass an :only option to your callback to filter to specify which attribute updates you're interested in. For example, to warn users whenever their credit card has changed:

class StripeMailer
  include Stripe::Callbacks

  after_customer_updated! :only => :active_card do |customer, evt|
    your_credit_card_on_file_was_updated_are_you_sure_this_was_you(customer).deliver
  end
end

Filters can be specified as an array as well:

module Accounting
  include Stripe::Callbacks

  after_invoice_updated! :only => [:amount, :subtotal] do
    # update our records
  end
end

Alternatively, you can just pass a proc to filter the event manually. It will receive an instance of Stripe::Event as its parameter:

module StagingOnly
  include Stripe::Callbacks

  after_charge_succeeded! :only => proc {|charge, evt| unless evt.livemode} do |charge|
    puts "FAKE DATA, PLEASE IGNORE!"
  end
end

Catchall Callback

The special 'stripe.event' callback will be invoked for every single event received from stripe.com. This can be useful for things like logging and analytics:

class StripeFirehose
  include Stripe::Callbacks

  after_stripe_event do |target, event|
    # do something useful
  end
end

See the complete listing of all stripe events, and the webhook tutorial for more great information on this subject.

Unit testing

If you want to test your callbacks, you can use the Stripe::Rails::Testing module to send mocked Stripe events.

require 'stripe/rails/testing'
test "my callback handles new subscription" do
  Stripe::Rails::Testing.send_event "customer.subscription.created"
  # Assertions
end

You can also overwrite some event properties: (More info)

require 'stripe/rails/testing'
test "my callback handles new subscription" do
  Stripe::Rails::Testing.send_event "customer.subscription.created", {
    :email => "[email protected]",
    :account_balance => 40
  }
  # Assertions
end

The default fixtures come from the stripe-ruby-mock gem.

Thanks

Stripe::Rails was originally developed with love and fondness by your friends at Frontside. They are available for your custom software development needs, including integration with stripe.com.

Stripe::Rails has also been supported by the fine folks at Evercondo, the next generation condo management software.

Code of Conduct

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms, which can be found in the CODE_OF_CONDUCT.md file in this repository.