jakanapes.com

According the the Riding Rails Blog the final release for Rails 3.0 should be this week. Lots of tweaks and bug fixes, but the things most people (including me!) are excited about are the new methods for handling gems (Bundler) and ARel. Accessing models using relational algebra. Should be much more efficient!

So as happy as I am with my action caching over on Alternity, there is one problem that’s bugging me.

I’d like each world and category to have a title that reflects the content. I put the content_for :title in my views, threw a yield :title in my layout and as expected, each of my pages had an appropriate title. Committed the change and didn’t think about it too much afterward until I noticed that there was no custom title on my live site. Duh, the content_for method is called when the view is rendered and since my action caching was fetching the pre-rendered *.cache files from my cache, naturally there was no :title for the layout to render. One solution would be to simply include the layout in the action cache, but I have reasons for not wanting to do that. It makes cache invalidation a bear.

I looked up how content_for worked and found that it simply saved the text into an instance variable:
@content_for_{name_of_the_content_block}
@content_for_title in my case.

It seems like the way to fix this would be to have the action cacher check for those instance variables and append them to the bottom of the *.cache files, then check for them when rendering and put them back into an instance variable.

Say, a chunk of text at the bottom of the file:

content_for_title blah blah blah
content_for_nav blah blah blah

Anybody done anything similar? I’m planning it out, but I want to wait until Rails 3 drops to see if there’s changes to the caching.

If you want to hurry up the indexing of the links on your site, it helps to have a sitemap. Google has a handy way to upload one: Webmaster Tools.

The problem can be generating one. There are a number of tools online (most of them cost money beyond a certain link count) or you can hand create the xml and submit, but your best bet is to create a script and auto-generate the sitemap frequently. Since my Alternity site is in Ruby on Rails, I decided to create a quick rake task to do the deed.

So in lib/tasks, I created a file called alternity_sitemap.rb

namespace :alternity do
  desc "Create a google sitemap"
  task :sitemap => :environment do
    include ActionController::UrlWriter
    default_url_options[:host] = 'alternity.jakanapes.com'
 
    #do a bunch of ruby code to generate the xml in the format described on the google webmaster pages
 
   sitemap = File.new("#{RAILS_ROOT}/public/alternity_sitemap.xml",  "w")
 
    sitemap.write(xml)
 
    sitemap.close
  end
end

:sitemap => :environment is so I can pull in my models
include ActionController::UrlWriter pulls in the url helper (i.e. worlds_url)
default_url_options[:host] = ‘alternity.jakanapes.com’ sets the base host of the url

I set up a cron job to run rake alternity:sitemap once a month and pointed the google webmaster tools to that location.

I quickly went from less than 100 indexed links to nearly 2000!

So if you’ve done any Ruby on Rails work with something that’s dynamically fetched but has pretty static content (like my worlds over on Alternity) then you know the joy of action caching.  Personally, I was seeing a speed increase of around 10x when fetching the cached page.

I got my caching and cache invalidation going, but ran into another problem when I attached admin actions to items.  I wanted to add an edit link to an item when I was logged in as an admin user.  Of course, if the page had been cached, I would never see the link and if it was the first time to view the page, then the edit link would get cached.

My solution was to add an around toggle to those actions that I would be doing editing on:

def toggle_caching
ActionController::Base.perform_caching = !ActionController::Base.perform_caching if session[:logged_in]
 
yield
 
ActionController::Base.perform_caching = !ActionController::Base.perform_caching if session[:logged_in]
end

Works like a champ.  My admin views are a little slower, but since I’m the only one who sees them, I can’t say I care that much.

If anyone knows of a better way, though, I’d love to hear it.