If you’re using fragment caching and you’re application is deployed to a hosting provider with multiple slices. don’t forget to define the location of the cache and store your cache in a location that all slices have access to. by default rails stores the cache in /tmp/cache , normally I would point it to RAILS_ROOT + tmp/cache

Here’s how to explicitly define the location of your cache:

Just need to define this in your environment.rb or create a file in the initializers directory.

ActionController::Base.fragment_cache_store = :file_store, "/path/to/cache/directory"

Some links about caching that I find very useful:

http://www.railsenvy.com/2007/2/28/rails-caching-tutorial

http://www.railsenvy.com/2007/3/20/ruby-on-rails-caching-tutorial-part-2

The Mechanics:

• Each team is given a question.
• Each team will create a working web application prototype in 1 day ( 12 hours ), based on the the solution to the question
• With team mates that we will be working with for the first time.
• Every team will start from scratch.
• You can use any tool available.
• The application will be made with rails.

The team I’m in got the question : “I smoke a pack a day. How many years before I die?”. My Teammates are marjun , and rachel. marjun and I work at the same office but rachel works at the cebu office.

We all got our questions 3 days before the event so we had time to research about the question and come up with an idea. I stumbled across this website here. And obviously it answered the question. We were lucky to have been given such an easy question. but The moment I saw that site I have been asking myself questions as to how can our application be different, I guess I was just so obsessed on being different. And thats what I did until the day of the hackathon arrived.

On the day of the hackathon, The first thing we did was find a means of communication. Which gave us our first problem. Our first option was to use yahoo messenger. Since its what we normally use in the office with regular work. but I was using adium, marjun was using pidgin and rachel I think she was using the original yahoo client. So we tried to make a chat room . Unfortunately I’m not sure if this is a bug but I can’t get their invite. so that didn’t work. The next option is to use old school irc. It went fine for a while. but The Cebu office had problems with their connection , it became intermittent and rachel missed a couple of conversations because of that. So we finally chose to use campfire. Went ok from there on, because even if rachel gets disconnected she can still see past conversations and its web based so even if we are using different operating systems, its not an issue.

While undergoing communication problems , we went ahead and tried to discuss how we were going to go about it. Here were our agendas:

1. Which Rails version are we going to use?
2. Which authentication plugin are we going to use?
3. How are we going to build the layout? ( we are three backend developers no ui person )
4. What features are we going to put in?
5. Which plugins/gems are we going to install in order to support the features we decide on?
6. How are we going to split up the tasks?

And thats about it for the first part.

Lets say you have a view which uses the date helper datetime_select like so:

<% form_for(:ticket, :url => tickets_path) do |f| %>
  	 <%= f.text_field :title -%>
  	 <%= f.text_field :description -%>
  	 <%= f.datetime_select :date_this_ticket_might_get_resolved -%>
<% end %>

And here’s a sample controller:

class TicketsController < ApplicationController

	def	create
		@ticket = Ticket.new(params[:ticket])
		@ticket.save
	end

end

And lastly the model:

class Ticket < ActiveRecord::Base

  	 def date_this_ticket_might_get_resolved=(val)
    	 	self.date_of_submission = Time.mktime( val[:year], val[:month], val[:day], 
                                            val[:hour], val[:minute]) + 1.year
  	 end

  	 def date_this_ticket_might_get_resolved
    	 	self.date_of_submission + 1.year # add another year just to be sure
  	 end

end

You will get something like this error:

NoMethodError (You have a nil object when you didn’t expect it!
The error occurred while evaluating nil.klass):
    /vendor/rails/activerecord/lib/active_record/base.rb:2645:in `execute_callstack_for_multiparameter_attributes’
    /vendor/rails/activerecord/lib/active_record/base.rb:2644:in `each’
    /vendor/rails/activerecord/lib/active_record/base.rb:2644:in `execute_callstack_for_multiparameter_attributes’
    /vendor/rails/activerecord/lib/active_record/base.rb:2630:in `assign_multiparameter_attributes’
    /vendor/rails/activerecord/lib/active_record/base.rb:2375:in `attributes=’

I was using Rails 2.1 with Ruby 1.8.6 , The patch can be found on this link, Just follow the instructions its just a one liner change on ActiveRecord::Base.