app.rb

post '/charge' do
  # Output the params hash with the values from Checkout in the bash
  puts params.inspect
  
  # Store Stripe Token and Customer Email Address in local variables
  token = params[:stripeToken]
  email = params[:stripeEmail]
  
  # Create a new Customer
  # Store the Response in a local variable
    customer = Stripe::Customer.create(
      :source => token,
      :email => email,
      :description => "Ruby customer"
    )
    
    # Charge the Customer instead of the card
    Stripe::Charge.create(
        :amount => 2000, # in cents
        :currency => "eur",
        :customer => customer.id
    )
    
    # Output the Customer ID to the user
    "Successfully created customer with ID: #{customer.id}"
end