Chargify API coupon creation

I am currently working on a project and facing a problem with a task. I am trying to randomly generate a 6 digit coupon number and post it to chargify account via there API. If the coupon creation is successful I want the same coupon code to be send to the customer through Email.

As per chargify documentation this is how I should send all the details to chargify from my application :

{"subscription":{
      "product_handle":"[@product.handle]",
      "customer_attributes":{
        "first_name":"Joe",
        "last_name":"Blow",
        "email":"joe@example.com"
      },
      "credit_card_attribute开发者_如何学编程s":{
        "full_number":"1",
        "expiration_month":"10",
        "expiration_year":"2020"
      },
      "coupon_code":"6 digit random code"
    }}
    """

https://[@subdomain].chargify.com/subscriptions.json.

I am able to create a 6 digit random numerical code by this method :

rand(999999).to_s.center(6, rand(9).to_s).

However this does not seem to be working for me. Any suggestions would be highly appreciated.

Thanks

---

I'm not part of our tech or dev staff, but I'm 99% sure you can only specify a previously-defined coupon code in that API call. You must define coupon codes in the Chargify admin web interface. In the API call above, you can apply a coupon to the subscription, but the assumption is that you already defined that coupon code in the admin interface.

We will add that capability in the future, but I don't have a specific date for you.

Sorry about that.

--- Lance Walley --- Chargify

---

I'm not sure what you're trying to do with your call to center. The most sensible thing to do would be to zero-fill the coupon code. This would do it:

"%06d" % rand(1000000)

This will generate codes such as "664001" and "061532".

Note that you want rand(1000000) rather than rand(999999). That's because rand gives you random integers between 0 and one less than the argument. rand(999999) will only give you random numbers up to 999998.

There's a violation of DRY (Don't Repeat Yourself) in the above code: Both the "06" and the "1000000" depend upon the length of the coupon code. Here's a fix for that:

COUPON_CODE_LENGTH = 6
"%0#{COUPON_CODE_LENGTH}d" % rand(10 ** COUPON_CODE_LENGTH)

Although longer, there's now only one thing to change if the coupon code length should change. The replacement of "magic numbers" with a named constant also helps the code to communicate its intent.