I have a user model subclassed into Employees and Managers using STI. I
am using FileColumn to manage images, in this case logos. If an Employee
doesn’t have a logo of its own, I want my app to use the Manager’s logo
in views.
I did the following in models/users.rb:
class User < ActiveRecord::Base
file_column :logo
end
class Employee < User
belongs_to :Manager
def logo
self[:logo] || self.manager[:logo]
end
end
class Manager < User
has_many :employees
end
When I call <%= @user.logo %> and @user is an Employee, it returns the
correct filename, using the Employee’s when one is set, and otherwise
falling back on the Manager’s.
However, none of the file_column methods are available. All I’m getting
in @user.logo is a string. @user.logo.relative_path, for instance,
returns nil, as do calls to url_for_file_column. Obviously all my
accessor is returning is a string attribute, noit a file_coilumn. Is
there a sensible way in my model to get the behavior I want, i.e. to
override the default read accessor and return a file_column with the
methods and attributes automagically brought along?
I suppose I could replace instances of url_for_file_column with a custom
helper that checks the user object type and generates a
url_for_file_column for either the Employee or Manager as needed, but I
also use this in an ActionMailer template, and bringing view helpers
into there gets ugly.
Thanks.