Order Fulfillment Strategy

Owned by steveR (Deactivated)
Last updated: Feb 12, 2015

This page covers the design ideas for Order Fulfillment in Django-Oscar. 

General Idea:

  • Fulfill enrollments synchronously through the Enrollment API.
  • Persist fulfillment status in django-oscar based on success or failure of request to Enrollment API.
  • Allow manual resubmission of failed fulfillment from django-oscar, if the Enrollment API fails to enroll students.

Related Sections of Code in django-oscar

  • order.processing.EventHandler is responsible for fulfillment via the "handle_shipping_event()" function. 
  • For all our digital product types, "handle_shipping_event()" will need to be extended to handle fulfillment.
    • Each ProductType will require unique fulfillment actions, such as Enrollments requiring the Enrollment API.
    • Each ProductType must have a unique fulfillment strategy defined in a new fulfillment API.
  • We can use Order Status via order.abstract_models.AbstractOrder to have statuses for failed fulfillment.

Fulfillment API

  • order.processing.EventHandler#handler_shipping_event() calls fulfillment_api.fulfill(order)
  • settings.py has a configured mapping of ProductTypes to Fulfillment classes

fulfillment.py

  • New fulfillment API module that has two functions
    • fulfill(order)
    • refund(order)
  • Each function returns status on whether on success or failure.
    • TODO: Need to identify all failure scenarios and map them to Order Status

Fulfillment Modules

  • There will be a base fulfillment module that has the following interface:
    • fulfill_product(product)
    • refund_product(product)
  • There will be an implementation per ProductType of "Fulfillment"
  • For Q3 we only need the EnrollmentFulfillment implementation.
  • EnrollmentFulfillment will contain the logic to call the Enrollment API synchronously to enroll a student.

 

Remaining Work

  • Create a ProductType Definition (stories exist)
  • Fulfillment API
    • Wired into EventHandler
    • Takes an Order
    • Fulfills associated products
    • Updates Order status
  • Define order status
    • state machine
  • Update the Marketing Site to call into the new endpoint
  • Course Mode table with SKUs for checking whether to use the new or old order workflows (short term)
  • Login and Registration Pages
  • Third Party Enrollment
  • Bypassing Payment (via RESTful API work)
    • Need to extend for payment gateways
    • Can have additional logic for bypassing payment on free products
    • The sandbox store has business logic for bypassing payment of free products as well.

 

Other Concerns

  • Error Handling on order fulfillment
    • Need celery task (or other queue) to re-attempt fulfillment on failed orders
  • Incremental rollout means there will be a need to update the course modes table as well as Oscar
    • Have a SKU table in the LMS that references rows in course_modes table (or add a new column)
    • Pass the SKU through the Enrollment API
    • Allows Drupal to build URLs based on the Enrollment API that can be used to purchase enrollments through Oscar.