How to handle partial updates of domain objects

[aloisbarreras]

HI @benbjohnson thanks for the great tutorials and code examples. I have a question about how you would handle an API route that can do partial updates. It's a fairly common pattern you see that only the fields specified in the body of the request are updated and any fields not specified will be unchanged.

I currently handle this using an Optional type like so:

type Optional[T any] struct {
	Valid bool
	Value *T
}

then for example we could modify the UserUpdate struct from this repo to look like this:

// UserUpdate represents a set of fields to be updated via UpdateUser().
type UserUpdate struct {
	Name  Optional[string] `json:"name"`
	Email Optional[string] `json:"email"`
}

and in the sqlite package when constructing the query, you can do (pseudocode):

if upd.Name.Valid {
    // add to the query
}

if upd.Email.Valid {
  // add to the query
}

This seems like kind of a gray area where it's not quite related to the domain and business logic, and I feel like it could be argued that it's leaking implementation details into the domain. I don't want to be too dogmatic about it, so I'll probably continue with this pattern, but I wanted to check if there was a different way of doing this that I hadn't thought of and how you've handled something like this in your experience.

Thanks!