Say you have an app not dissimilar to StackOverflow where users vote on posts. Say an Up Vote causes the voter to receive one reputation point. You might see something like this in the vote_up model:
class UpVote < ActiveRecord::Base belongs_to :user after_create :increase_user_reputation private def increase_user_reputation user = self.user user.reputation == user.reputation + 1 end end There is one issue with this code: The value 1 is hard coded. Where does such a value belong? Another issue is that some UpVote should have no knowledge of user.reputation. We solve this by changing the callback: def increase_user_reputation self.user.modify_reputation(1) end Then we add an instance method to User: def modify_reputation(reputation) self.reputation = self.reputation + reputation self.save! end Questions... 1. Who's responsible for calling save! ? The *increase_user_reputation*inside the UpVote model or the *modify_reputation* method inside the user model? 2. The +1 one to reputation doesn't seem like a good idea to hard code. Where does Rails keep such configuration settings? 3. Does the code look reasonable? Are there any shortcuts? -- You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To view this discussion on the web visit https://groups.google.com/d/msg/rubyonrails-talk/-/_bQDSP0JAhsJ. To post to this group, send email to rubyonrails-talk@googlegroups.com. To unsubscribe from this group, send email to rubyonrails-talk+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en.