Add check to ensure that a team member has atleast one Access Role selected

app/models/users_project.rb

@@ -9,6 +9,7 @@ class UsersProject < ActiveRecord::Base
   validates_uniqueness_of :user_id, :scope => [:project_id]
   validates_presence_of :user_id
   validates_presence_of :project_id
+  validate :user_has_a_role_selected
 
   delegate :name, :email, :to => :user, :prefix => true
 
@@ -18,6 +19,10 @@ class UsersProject < ActiveRecord::Base
     end
   end
 
+  def user_has_a_role_selected
+    errors.add(:base, "Please choose at least one Role in the Access list") unless read || write || admin
+  end
+
 end
 # == Schema Information
 #