aa-stripe 0.10.0

Stripe integration for Django-based projects

Stripe integration for Django-based projects

This project’s target is to make the Stripe API easier to use in Django-based applications. At the moment the library supports:

• charging users

• plans

• subscriptions

• webhooks

Support for Python 2.7 has been dropped since aa-stripe 0.6.0.

Installation

Add aa_stripe to your app’s INSTALLED_APPS, and also set STRIPE_API_KEY in project settings. After all please migrate the app (./manage.py migrate aa_stripe). Add STRIPE_WEBHOOK_ENDPOINT_SECRET into your settings from stripe webhooks configuration to enable webhooks. Add STRIPE_USER_MODEL if it is different than settings.AUTH_USER_MODEL. In example when CC is connected to office not person. STRIPE_USER_MODEL defaults to AUTH_USER_MODEL.

Add aa_stripe.api_urls into your url conf.

Usage

Creating a token for user

Use stripe.js (https://stripe.com/docs/stripe.js) to get single use token (stripe.js->createToken) and send it to API using /aa-stripe/customers to create Customer for the user. It runs:

customer = stripe.Customer.create(source=data["id"]) # data is the response dictionary from Stripe API (in front-end)
token = StripeToken.objects.create(user=request.user, content=data,
                                 customer_id=customer["id"])

This endpoint requires authenticated user. In case you need diferent implementation (like one call with register) you’ll have to adjust your code.

Charging

First of all, make sure to obtain Stripe user token from the Stripe API, and then save it to aa_stripe.models.StripeToken, for example:

import stripe
from aa_stripe.models import StripeToken

customer = stripe.Customer.create(source=data["id"]) # data is the response dictionary from Stripe API (in front-end)
token = StripeToken.objects.create(user=request.user, content=data,
                                   customer_id=customer["id"])

To charge users, create an instance of aa_stripe.models.StripeCharge model and then call the charge() method:

c = StripeCharge.objects.create(user=user, token=token, amount=500,  # in cents
                                description="Charge for stuff",  # sent to Stripe
                                comment="Comment for internal information",
                                statement_descriptor="My Company" # sent to Stripe
)
c.charge()

Upon successfull charge also sends signal, stripe_charge_succeeded with instance as single parameter.

If charge fails due to CardError, charge_attept_failed is set to True and this charge will not be automatically retried by charge_stripe command. Signal stripe_charge_card_exception with instance and exception will be send.

There is also a management command called charge_stripe in case you need to process all the remaining charges or to run it by cron.

Subscriptions support

With Stripe user token already obtained you can create subscription.

import stripe
from aa_stripe.models import StripeSubscription

subscription = StripeSubscription.objects.create(
  customer=self.customer,
  user=self.user,
  plan=self.plan,
  metadata={"name": "test subscription"},
)

The newly created object is not sent to Stripe just yet.

subscription_data = subscription.create_at_stripe()

The command above returns whole subscription data send by stripe, including, in example, discounts.

https://stripe.com/docs/api#subscriptions

Utility functions for subscriptions

• subscription.refresh_from_stripe() - gets updated subscription data from Stripe. Example usage: parsing webhooks - when webhook altering subscription is received it is good practice to verify the subscription at Stripe before making any actions.

• subscription.cancel() - cancels subscription at Stripe.

• StripeSubscription.get_subcriptions_for_cancel() - returns all subscriptions that should be canceled. Stripe does not support end date for subscription so it is up the user to implement expiration mechanism. Subscription has end_date that can be used for that.

• StripeSubscription.end_subscriptions() - cancels all subscriptions on Stripe that has passed end date. Use with caution, check internal comments.

• management command: end_subscription.py. Terminates outdated subscriptions in a safe way. In case of error returns it at the end, using Sentry if available or in console. Should be used in cron script. By default sets at_period_end=True.

Subscription Plans

Subscription Plans can be created using Stripe UI however there are cases when those needs to be created using API.

import stripe
from aa_stripe.models import StripeSubscriptionPlan

plan = StripeSubscriptionPlan.objects.create(
  source={"a": "b"},
  amount=5000,
  name="gold-basic",
  interval=StripeSubscriptionPlan.INTERVAL_MONTH,
  interval_count=3,
)

As with Subscription, the object has to be sent to stripe.

plan_data = plan.create_at_stripe()

The command above returns whole plan data send by stripe.

https://stripe.com/docs/api#plans

Coupons Support

Stripe coupons can be created both in the Stripe Dashboard and using the aa_stripe.models.StripeCoupon model, and also if webhooks are properly configured in your app, you will be able to see all changes related to coupons made in the Stripe Dashboard. This works both ways, if a coupon was created, edited or deleted on the application side, the list of coupons in Stripe will be updated respectively.

from aa_stripe.models import StripeCoupon

coupon = StripeCoupon.objects.create(
    coupon_id="SALE10",
    duration=StripeCoupon.DURATION_FOREVER,
    currency="usd",
    amount_off=10,  # in dollars
)
# coupon was created at Stripe
coupon.delete()
# coupon was deleted from Stripe, but the StripeCoupon object is kept
print(coupon.is_deleted)  # True

Important: When updating coupon data, do not use the StripeCoupon.objects.update() method, because it does not call the StripeCoupon.save() method, and therefore the coupon will not be updated at Stripe.

The refresh_coupons management command

To make sure your app is always up to date with Stripe, the refresh_coupons management command should be run chronically. It allows to periodically verify if all coupons are correctly stored in your app and no new coupons were created or deleted at Stripe.

For more information about coupons, see: https://stripe.com/docs/api#coupons

Webhooks support

All webhooks should be sent to /aa-stripe/webhooks url. Add STRIPE_WEBHOOK_ENDPOINT_SECRET to your settings to enable webhook verifications. Each received webhook is saved as StripeWebhook object in database. User need to add parsing webhooks depending on the project. Be advised. There might be times that Webhooks will not arrive because of some error or arrive in incorrect order. When parsing webhook it is also good to download the refered object to verify it’s state.

Stripe has the weird tendency to stop sending webhooks, and they have not fixed it yet on their side. To make sure all events have arrived into your system, the check_pending_webhooks management command should be run chronically. In case there is more pending webhooks than specified in the STRIPE_PENDING_WEBHOOKS_THRESHOLD variable in your settings (default: 20), an email to project admins will be sent with ids of the pending events, and also the command will fail raising an exception, so if you have some kind of error tracking service configured on your servers (for example: Sentry), you will be notified. Also if ENV_PREFIX is specified in your settings file, it will be included in the email to admins to indicate on which server the fail occurred.

By default the site used in the check_pending_webhooks command is the first django.contrib.sites.models.Site object from the database, but in case you need to use some other site, please use the --site parameter to pass your site’s id.

Parsing webhooks

To parse webhooks, you can connect to the aa_stripe.models.webhook_pre_parse signal, which is sent each time a StripeWebhook object is parsed.

Sample usage:

from aa_stripe.models import StripeWebhook, webhook_pre_parse

def stripewebhook_pre_parse(sender, instance, event_type, event_model, event_action, **kwargs):
    if not instance.is_parsed:
        # parse

webhook_pre_parse.connect(stripewebhook_pre_parse, sender=StripeWebhook)

Arguments:

• sender - the StripeWebhook class

• instance - the StripeWebhook event object

• event_type - Stripe event type (for example: coupon.created, invoice.payment_failed, ping, etc., see: https://stripe.com/docs/api#event_types)

• event_model - the model which created the event (for example: coupon, invoice, charge.dispute, etc.)

• event_action - the action done on the event_model (for example: created, updated, payment_failed, etc.)

Both event_model and event_action equal to None if event_type is a ping event.

Updating customer card data

StripeCustomer.sources list is updated after receiving Webhook from Stripe about updating the customer object. It is a list of Stripe source objects.

Another way of updating the credit card information is to run the refresh_customers management command in cron.

Support

• Django 2.2-3.1

• Python 3.6-3.8