```ruby
class Api::BraintreeController < ApplicationController

  def token
    render json: { token: ::Braintree::ClientToken.generate }
  end

  def transaction
    sale = braintree.make_transaction(options)

    if sale.success?
      render json: { success: true, transaction_id: sale.transaction.id }
    else
      render json: { success: false, errors: sale.errors }
    end
  end

  private

  def options
    {
      nonce: params[:payment_method_nonce],
      user: params[:user],
      amount: params[:amount].to_f,
      store: Payment
    }
  end

  def braintree
    PaymentProcessor::Clients::Braintree::Transaction
  end
end
```

Add controller handling for subscriptions, rename the transaction-specific methods
user
```ruby
class Api::BraintreeController < ApplicationController

  def token
    render json: { token: ::Braintree::ClientToken.generate }
  end

  def transaction
    result = braintree::Transaction.make_transaction(transaction_options)
    if result.success?
      render json: { success: true, transaction_id: result.transaction.id }
    else
      render json: { success: false, errors: result.errors }
    end
  end

  def subscription
    result = braintree::Subscription.make_subscription(subscription_options)
    if result.success?
      render json: { success: true, subscription_id: result.subscription.id }
    else
      render json: { success: false, errors: result.errors.for(:subscription) }
    end
  end

  private

  def transaction_options
    {
      nonce: params[:payment_method_nonce],
      user: params[:user],
      amount: params[:amount].to_f,
      store: Payment
    }
  end

  def subscription_options
    {
      amount: params[:amount].to_f,
      plan_id: '35wm',
      payment_method_token: Payment.customer(params[:email]).default_payment_method.token
    }
  end

  def braintree
    PaymentProcessor::Clients::Braintree
  end
end
```
assistant