Fulfilling product orders or how do I find the products a user purchased?

[caged]

👋 Thank you for the work on this. I have a question related to two previous ones (#443 #460), but I'm still not sure they answer my question after kicking around different ideas on how to solve my issue.

In short, how can I tell which products a user has purchased?

1. I have multiple products called things
2. A user can buy a Thing (Stripe Product) through the checkout process. They can also come back later and buy another Thing through a second checkout process.
3. I want to know what products the user has purchased. (e.g. user.purchased_things).

I've likely been staring at this too long, and I suspect I have been, because this seems like something this libray should be able to do.

The problem I'm having is that I'm unable to reliably get the associations and ids needed through webhooks or model concern extensions, even when using metadata.

Checkout with metadata

The metadata sent here is only available in the checkout.session.completed webhook.

class CheckoutsController < ApplicationController
  before_action :authenticate_user!
  before_action :set_course

  def show
    current_user.set_payment_processor(:stripe)
    current_user.payment_processor.customer

    @payment = current_user.payment_processor.checkout(
      mode: 'payment',
      line_items: 'price_123456789',
      metadata: {
        user_id: current_user.id,
        thing_id: @thing.id
      }
    )
  end
end

Fulfillment in webhooks

stripe.charge.succeeded

• metadata is empty in the stripe.charge.succeeded webhook.
• There's no reference to the Stripe Product.
• I know the customer, and that they were charged, but I don't know the Thing they bought.

class ChargeSucceeded
  def call(event)
    Rails.logger.info(event)
  end
end

stripe.checkout.session.completed

• metadata is available here!
• There's no way to get a reference to a charge. Now I have a way to get references to the User and Thing, but no way to find what charge is associated with this session.

class CheckoutSessionCompleted
  def call(event)
    Rails.logger.info(event)
  end
end

Fullfillment using Extensions/Concerns

• metadata is empty here
• no way to get a reference to the thing_id

module ChargeExtensions
  extend ActiveSupport::Concern

  included do
    after_create :fulfill_order
  end

  def fulfill_order
    Rails.logger.info(metadata)
  end
end

Any ideas where I've went astray here? Should metadata passed at checkout time, be available in the Charge object and in stripe.charge callbacks?

Thanks for your time! 🙏🏻

[caged]

I was kind of able to achieve this in the stripe.checkout.session.completed since I have access to both the user and the thing, so I can assume the user just made a purchase for the thing, however I'm still not sure how to tie that purchase back to a Charge object.

[cjavilla-stripe]

This is a little tricky because the line_items for the Checkout Session are not included in the webhook payload. Reference to the Price ID and the Product ID for each line item purchased on a Checkout Session is only available through the Checkout Session (with expand), not the PaymentIntent or Charge.

Here's how I'd solve:

checkout_session_id = event.data.object.id

checkout_session = Stripe::Checkout::Session.retrieve({ id: checkout_session_id, expand: ['line_items'] })
checkout_session.line_items.each do |line_item|
  # Do stuff to create Things here:
  puts line_item.price # Price object
  puts line_item.price.product # Product ID (you can change to `expand: ['line_items.data.price.product']` if you want the full product obj)
end

[caged]

Thanks for the suggestion @cjavilla-stripe. Using your example I was able to fill out a local Purchase model with enough info to make me comfortable that a user purchased a thing.

That leave's Pay's Charge object kind of orphaned out of the box for basic Product purchases. Subscriptions, on the other hand, have a foreign key and reference in the charges table. Correct me if I'm wrong, but here is my understanding of the out-of-the-box functionality (no custom webhooks or concerns):

You can

• Charge a user for a Stripe Product using a price_id.
• Get a users charges user.charges or user.payment_processor.charges

You can't

• Reference what Product a user was charged for using the Charge API or internal APIs.
• Reference who purchased a Product (thing.charges) using the Charge object or internal APIs.
• Fulfill product orders without implementing your own webhooks and join model. These docs suggests Pay will create a subscription for you, but similar features seem to be missing for Product purchases.

I believe there are two things that would help, individually, or together.

1. If Pay had a similar pay_products table, mirroring pay_subscriptions and if there was a reference to that table in pay_charges.
2. If Pay passed the metadata sent at checkout time to all callbacks or if there were references to the product_id and/or price_id in the Charge callbacks.

FWIW, I'm not complaining about missing functionality if it seems that way. I'm implementing in-app payments for the first time and trying to stay on the golden path if possible. I would love to be wrong 😄

Thanks for your time! I'm happy to mark this as answered, if you believe it to be. 🙏🏻