如何创建支付意图等于 $ 0 的条带或其他替代方案的订阅？

Question

我正在使用 Stripe 元素创建订阅，一切都很好......除非数量支付意图是 0 美元

来自 Stripe PaymentIntent 文档：

 The minimum amount is $0.50 US or equivalent in charge currency.

在这里，我有使用条纹元素创建付款意图的方法

# Here I created an object of type subscription incompletely (@subscription)
# In such a way that the user can enter their credit card and with the help of 
# @subscriptions confirm if everything is fine
def checkout
    @subscription = Stripe::Subscription.create(
      customer: current_user.stripe_customer_id, # stripe customer_id for suscription 
      items: [{
        price: params[:price] # attached price of suscription plans
      }],
      payment_behavior: 'default_incomplete', # PaymentIntent with status=incomplete
      expand: ['latest_invoice.payment_intent'] # return the payment_intent data
    )
end

And it displays a checkout.html.erb where it will allow the user to place their card and then pay

# checkout.html.erb
<form id="payment-form">
  <div class="form-row">
    <label for="card-element">
      <!-- Debit/credit card -->
    </label>

    <div id="card-element">
      <!-- a Stripe Element will be inserted here -->
    </div>

    <!-- Used to display Elements errors -->
    <div id="card-errors" role="alert"></div>
  </div>

  <button id="submit">Submit Payment</button>
</form>

<script>
   // Initialize stripe elements
   var stripe = Stripe("<%= ENV['STRIPE_PUBLISHABLE_KEY'] %>");
   var elements = stripe.elements();
   var cardElement = elements.create('card');
   cardElement.mount('#card-element');

   var formElement = document.getElementById('payment-form');

   formElement.addEventListener('submit', function(event) {
     event.preventDefault();

  # here I create the payment intention but when the plan has a subscription of $ 0 
  # it 
  # does not recognize me neither the field client_secret nor the payment_intent

  stripe.confirmCardPayment("<%= 
     @subscription.latest_invoice.payment_intent.client_secret %>", {
    payment_method: { card: cardElement }
     }).then(function(result) {
    if (result.error) {
      console.log(result.error.message);
      window.location.reload();
    } else {
      window.location.href = "/" ;
    }
  });

 });

简而言之，一切对我来说都很好，除非付款意图是 0 美元并且文档说“最低是 0.50”

有没有办法用 0 美元创建订阅（即使金额为 0 美元，用户也必须插入有效的信用卡/借记卡才能订阅）？

例如：当我们订阅herokuapp而不花一美元获得更多权限时，我们甚至需要一张有效的卡，所以我们可以订阅heroku权限

谢谢你的时间

Answer 1

对于使用payment_behavior: default_incomplete创建的订阅，并且第一张发票是 $0，您应该在pending_setup_intent取回设置意图（请参阅api 参考）。 您不能为此使用付款意向，因为如果没有到期付款，Stripe 不会为发票生成付款意向。

您可以使用此 SetupIntent 收集带有 Card 元素的付款详细信息，然后使用stripe.confirmCardSetup （请参阅api 参考）完成对卡的配置以供将来使用。