Question

I’m on Rails 3.0. For a model’s updated_at column, I need to output that as a user friendly format in JSON, so instead of seeing this 2011-09-14T22:01:32Z as the value, I would like to show less than a minute ago (or whatever user-friendly message I decide) for updated_at. I wrote a method that returns the output in the user-friendly format and now needs the functionality to be available in views, controller and model. What’s the best way to do this so it isn’t convoluted or bad practice.

EDIT Per answer from @klochner, here’s what my date.rb looks like but now it throws date.rb:21:informat’: wrong number of arguments (2 for 0) (ArgumentError)`

include ActionView::Helpers::DateHelper

class ActiveSupport::TimeWithZone
  def friendly
    format
  end
end

class Date
  def friendly
    format
  end
end

class Time
  def friendly
    format
  end
end

def format
  if self.today?
    format_time = ...
  elsif (self < Time.now.beginning_of_day) and (self > Time.now.yesterday.beginning_of_day)
    format_time = ...
  else
    format_time = ...
  end
end

@klochner suggestion changing format to format_helper works great. Thanks!

Answer 1

MonkeyPatch the ActiveSupport::TimeWithZone class, here’s what I do (I put this in config/initializers/date.rb)

class ActiveSupport::TimeWithZone
  def mdy
    self.strftime("%m/%d/%Y")
  end
end
class Date
  def mdy
    self.strftime("%m/%d/%Y")
  end
end
class Time
  def mdy
    self.strftime("%m/%d/%Y")
  end
end

Then for any date object (or date field in an AR model), you can call mdy():

 > Time.now.mdy
 => "09/14/2011" 
> User.first.created_at.mdy
 => "02/27/2009" 
> Date.today.mdy
 => "09/14/2011" 

For json, you probably want to write an as_json method for the model that you’re rendering. See this related answer:
render :json does not accept options