Make ActiveResource able to handle authentication w/o acting like a global variable.

resource_factory.rb

# This is a gross hack to make it possible to access the same
# resource from the context of different users at the same time.
# I'm quite positive this is wasteful and bad, but it's the only
# way to 'de-global' subclasses of ActiveResource::Base. :(  It's
# also possible it leaks memory if the GC doesn't collect Class
# objects. -- Morgan Schweers, 09-Nov-2009

class ResourceFactory
  def self.get(klass)
    Class.new(klass) do |resource|
      resource.collection_name = klass.collection_name
      resource.element_name = klass.element_name
      resource.format = klass.format
    end
  end
end

# Usage (presuming a Message class exists, descended from ActiveResource::Base):
#   from = ResourceFactory.get(Message)
#   from.user='morgan'
#
#   to = ResourceFactory.get(Message)
#   to.user='corwin'
#
#   to.find(1)
#   from.find(1)