This is an issue we have ran into multiple times now... very much looking forward to others' opinions!
Scenario Description (for illustration purposes):
Somebody visits our website, perhaps they fill out some forms, whatever. To us, this person is a prospect/lead. They have not been fully onboarded as a customer; they are simply a potential future customer.
Certain actions can be performed on these Prospects, such as adding certain data to their profile. Let's call this add_foobar_data. Of course, if they become a real customer (somebody consuming our service), we still need to be able to add/remove said data from their account.
Scenario (tl;dr):
Prospects can become Customersadd_foobar_data conceptually applies to both Prospects and CustomersProspects only have a subset of data of Customers (they are a true subset; currently Customers have a lot of non-nullable fields Prospects do not have)Options:
Create a union type, e.g. Customerable. add_foobar_data would return a Customerable (or backref to a Customerable) rather than a specific type.
Create separate mutations for modifying Prospects and Customers (add_foobar_data_to_prospect, add_foobar_data_to_customer)
Everybody is a Customer! Make all those non-nullable fields on Customer that are not in Prospect nullable and add a new flag called isProspect (or isDraft if we want to change how we think about the flow).
Perhaps some other approach I did not think of...
Anybody have thoughts on what is the best approach to this situation and why?
Ended up using an Interface since Prospect is a direct subset of Customer, and not by coincidence.