Set Up Your Server

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Install and configure


Requires Ruby 2.0 or later.

Add the braintree gem to your project's Gemfile:

gem "braintree", "~> 2.92.0"

And run bundle install to install it.

Construct your gateway object

In your code, you must first construct a gateway object with the environment-specific (sandbox or production) access token provided in your PayPal dashboard:

gateway =
  :access_token => use_your_access_token

This must be called before performing any method (e.g. client token generation, authorizations, captures).


Keep in mind that the step to initialize the gateway using the Express Checkout integration is different than that used for a direct integration with Braintree.

Generate a client token

Your server is responsible for generating a client token, which contains all the authorization and configuration information your client needs to initialize the client SDK to communicate with Braintree. The client-side page covers the client side of the exchange.

Send a client token to your client

Here is an example of how your server would generate and expose a client token:

get "/client_token" do

How the token is used by the client may vary. In JavaScript integrations the client token is often included in the generated HTML/JS, although you could load the client token from an AJAX call instead. These methods are discussed in the client token setup section.

Receive a payment method nonce from your client

Once your customer has successfully completed the PayPal checkout flow your client will receive a payment_method_nonce representing customer payment authorization, which it then sends to your server.

Your server implementation is then responsible for receiving the payment_method_nonce and creating a transaction.

post "/checkout" do
  nonce = params[:payment_method_nonce]
  # Use payment method nonce here...

Create a transaction

You can create a transaction using a payment_method_nonce and an amount. Below is an example of all relevant PayPal parameters you can pass in your transaction call:

gateway =
  :access_token => use_your_access_token

result =
  :amount => "10.00",
  :merchant_account_id => "USD",
  :payment_method_nonce => params[:payment_method_nonce],
  :order_id => "Mapped to PayPal Invoice Number",
  :descriptor => {
    :name => "Descriptor"
  :shipping => {
    :first_name => "Jen",
    :last_name => "Smith",
    :company => "Braintree",
    :street_address => "1 E 1st St",
    :extended_address => "Suite 403",
    :locality => "Bartlett",
    :region => "IL",
    :postal_code => "60103",
    :country_code_alpha2 => "US"
  :options => {
    :paypal => {
      :custom_field => "PayPal custom field",
      :description => "Description for PayPal email receipt",
if result.success?
  "Success ID: #{}"

Specify currency

The customer will be charged in the currency you specify in the merchant_account_id field on the transaction call. You should pass the same currency here that you specified on the client side.


If you don't pass the merchant_account_id field, the customer will be charged in the default currency for the country associated with your account.

The merchant_account_id field accepts the 3-letter currency code of each of the currencies currently enabled for your account. You can see these currencies on the My Apps & Credentials page in your PayPal Developer Dashboard.

Shipping addresses

PayPal validates the shipping address, so it must follow the PayPal address conventions.

Seller Protection

By passing a shipping address, you may also be eligible for PayPal Seller Protection. You can check the status of Seller Protection as follows:

transaction = braintree.gateway.find("the_transaction_id")


See also

The below are links to reference pages used by merchants performing direct integrations with Braintree. If you have questions about your Express Checkout integration, please be sure to contact PayPal Support rather than Braintree Support.

Next Page: Testing and Go Live →

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