Braintree::Configuration.environment = :sandbox
Braintree::Configuration.merchant_id = ''
Braintree::Configuration.public_key = ''
Braintree::Configuration.private_key = ''

customer = BraintreeRails::Customer.new(:first_name => 'Foo') # new record

customer.save! # => persisted

customer = BraintreeRails::Customer.new(customer.id) # fetched from Braintree for given id

customer = BraintreeRails::Customer.new(Braintree::Customer.find(customer.id)) # wrapping Braintree model objects

customer = BraintreeRails::Customer.create!(:first_name => 'Foo')

customer = BraintreeRails::Customer.find(customer.id)

customer.company = 'Foo Bar'

customer.save!

customer.update_attributes(:website => 'www.example.com')

customer.update_attributes!(:email => '[email protected]')

customer.destroy

customer = BraintreeRails::Customer.create!(:first_name => 'Foo')

customer.credit_cards # => []

credit_card = customer.credit_cards.build(
  :cardholder_name => 'Foo',
  :number => '4111111111111111',
  :cvv => '123',
  :expiration_month => '12',
  :expiration_year => '2020',
  :billing_address => {:street_address => 'Foo St', :postal_code => '12345'}
)

credit_card.save

transaction = credit_card.transactions.create!(:amount => '10.00') # => authorized

transaction.submit_for_settlement # => submitted_for_settlement

transaction.void! # => voided

transaction.void! # => raises Braintree::ValidationsFailed

credit_card = customer.credit_cards.build

credit_card.save! # => raises RecordInvalid

credit_card.errors # => ActiveModel::Errors

credit_card.valid? # => false

credit_card.assign_attributes(
  :cardholder_name => 'Foo',
  :number => '4111111111111111',
  :cvv => '123',
  :expiration_month => '12',
  :expiration_year => '2020',
  :billing_address => {:street_address => 'Foo St', :postal_code => '12345'}
)

credit_card.save! # => true

= simple_form_for @credit_card, :url => url, :html => { :class => 'form-horizontal' } do |f|
  = f.input :number if @credit_card.new_record?
  = f.input :cardholder_name
  = f.input :cvv, :maxlength => 4, :label => 'CVV'
  = f.input :expiration_month, options_for_month_select
  = f.input :expiration_year, options_for_year_select
  = f.simple_fields_for :billing_address, @credit_card.billing_address do |ba|
    = ba.input :first_name
    = ba.input :last_name
    = ba.input :company
    = ba.input :street_address
    = ba.input :extended_address
    = ba.input :locality, :label => 'City'
    = ba.input :country_code_alpha2, options_for_country_select
    = ba.input :region, options_for_region_select
    = ba.input :postal_code
  .form-actions
    = f.button :submit, :class => 'btn-primary'
    = link_to 'Cancel', user_customer_credit_cards_path(@user), :class => 'btn'

class TransactionsController < ApplicationController
  ...
  def index
    @transactions = (@credit_card || @customer).transactions
  end

  def new
    @transaction = @customer.transactions.build(:amount => "10.00")
  end

  def create
    @transaction = @customer.transactions.build(params[:transaction])
    if @transaction.save
      flash[:notice] = "Transaction has been successfully created."
      redirect_to user_customer_transaction_path(@user, @transaction.id)
    else
      flash.now[:alert] = @transaction.errors[:base].join("\n")
      render :new
    end
  end
  ...
end