Faster way to access prefix IDs for associated models

[cjavdev]

We started to bump up against performance issues when rendering lots of prefix IDs for subordinate objects in API responses. For example:

class Project < ARBase
  belongs_to :account
end

This causes an N+1 to fetch the account just to render it's prefix ID.

json.id project.prefix_id
json.account_prefix_id project.account.prefix_id

This also causes issues when we go to create a project with a prefix ID. Consider this:

project = Project.create!(account_id: "acct_abc123")

This fails unless we override the account_id setter method on Project so that it first finds the Account and then uses the found account's underlying ID like:

class Project
  belongs_to :account

  def account_id=(raw)
    super Account.find(raw).id # Has other deeper problems if not found
  end
end

[excid3]

Thanks @cjavdev! This is a great improvement.