Braintree subscription create XML with add-ons and discounts

gistfile1.txt

The type="array" is necessary

<subscription>                                                         
  <payment-method-token>the_payment_method_token</payment-method-token>
  <plan-id>the_plan_id</plan-id>                                       
  <add-ons>                                                            
    <add type="array">                                                 
      <item>                                                           
        <inherited-from-id>add_on_id_1</inherited-from-id>             
        <amount>20.00</amount>                                         
      </item>                                                          
    </add>                                                             
    <update type="array">                                              
      <item>                                                           
        <existing-id>add_on_id_2</existing-id>                         
        <quantity type="integer">2</quantity>                          
      </item>                                                          
    </update>                                                          
    <remove type="array">                                              
      <item>add_on_id_3</item>                                         
    </remove>                                                          
  </add-ons>                                                           
  <discounts>                                                          
    <add type="array">                                                 
      <item>                                                           
        <inherited-from-id>discount_id_1</inherited-from-id>           
        <amount>15.00</amount>                                         
      </item>                                                          
    </add>                                                             
    <update type="array">                                              
      <item>                                                           
        <existing-id>discount_id_2</existing-id>                       
        <quantity type="integer">3</quantity>                          
      </item>                                                          
    </update>                                                          
    <remove type="array">                                              
      <item>discount_id_3</item>                                       
    </remove>                                                          
  </discounts>                                                         
</subscription>