New to cacheing

rubyonrails-talk
1

Ok, So, I'm a bad developer and have never used any sort of cacheing before. I decided it's time I step up and I threw in some memcached magic. I'm still pretty new to all this, so I'm confused on how some things work. I've watched the railscast on cacheing, and gone through many tutorials.

So, the problem I'm having is that I have this page being cached, and it's not updating the page when I do any sort of CRUD action on the model primarily used on this page.

Here is what I have

class SiteController < ApplicationController   caches_action :index

  def index     #this in my home page   end en

class ListingsController < SiteController   #This is the page being cached   def index     @listings = Listing.all   end end

class ListingSweeper < ActionController::Caching::Sweeper   observe Listing

  def after_save(listing)     expire_cache(listing)   end

  def after_update(listing)     expire_cache(listing)   end

  def after_destroy(listing)     expire_cache(listing)   end

  def expire_cache(listing)     expire_action root_path     expire_action listings_path   end

end

When I create a new Listing, or update or destroy an existing one, it should clear the cache of the ListingsController#index, right?

When I go the the page, and refresh over and over, this is what pops up in my production.log

Processing ListingsController#index (for 12.34.567.58 at 2010-03-31 17:13:29) [GET] Filter chain halted as [#<ActionController::Filters::AroundFilter:0x2aaaae2804c8 @options={:if=>nil, :unless=>nil, :only=>#<Set: {"contact", "index"}>}, @method=#<Proc:0x00002aaaac2a3ec0@/var/rails/app/releases/20100331171209/vendor/rails/actionpack/lib/action_controller/caching/actions.rb:64>, @kind=:filter, @identifier=nil>] did_not_yield. Completed in 2ms (View: 0, DB: 0) | 200 OK [http://245.254.135.24/listings\]

Anyone have a good link for a tutorial I can get, or maybe an idea or what I might be missing?

Any help is much appreciated!

Thanks, ~Jeremy

2

Another odd thing maybe someone can clear up for me.

In my sweepers I currently have:

def expire_cache   expire_action root_path end

but my cache isn't being expired, so I figured I would put the route in manually

def expire_cache   expire_action :controller => 'site', :action => 'index' end

and I get this error:

ActionController::RoutingError (No route matches {:controller=>"admin/site", :action=>"index"}):

Now, obviously I'm updating the model in the admin section, but I'm not specifying my controller to be 'admin/site'. I just want to update object in the admin section, and update the cache on the front end of the site.

3

Have you added the sweeper to your list of observers in config/ environment.rb?

4

David wrote:

Have you added the sweeper to your list of observers in config/ environment.rb?

Actually, I had not. I had another sweeper, and my user observer in there. I will try that out, and post back what happens :slight_smile:

5

Jeremy Woertink wrote:

David wrote:

Have you added the sweeper to your list of observers in config/ environment.rb?

Actually, I had not. I had another sweeper, and my user observer in there. I will try that out, and post back what happens :slight_smile:

fail :frowning:

config.active_record.observers = :user_observer, :listing_sweeper

This is what I should have, right?

6

Have you added sweeper path ? config.load_paths += %W( #{RAILS_ROOT}/app/sweepers)

7

Quy Doan wrote:

Have you added sweeper path ? config.load_paths += %W( #{RAILS_ROOT}/app/sweepers)

Yes, and they seem to load ok. I don't get any errors for uninitialized constants or anything.

Environment.rb RAILS_GEM_VERSION = '2.3.5' unless defined? RAILS_GEM_VERSION require File.join(File.dirname(__FILE__), 'boot') Rails::Initializer.run do |config|   config.load_paths << "#{RAILS_ROOT}/app/sweepers"   config.active_record.observers = :user_observer, :listing_sweeper end

Production.rb config.cache_classes = true config.action_controller.consider_all_requests_local = false config.action_controller.perform_caching = true config.action_view.cache_template_loading = true config.cache_store = :mem_cache_store

config/initializers/cache_money.rb if RAILS_ENV != 'development'   require 'cache_money'   config = YAML.load(IO.read(File.join(RAILS_ROOT, "config", "memcached.yml")))[RAILS_ENV]   $memcache = MemCache.new(config)   $memcache.servers = config['servers']   $local = Cash::Local.new($memcache)   $lock = Cash::Lock.new($memcache)   $cache = Cash::Transactional.new($local, $lock)   class ActiveRecord::Base     is_cached :repository => $cache   end else   class ActiveRecord::Base     def self.index(*args)     end   end end

Thanks for all the suggestions. Please, if anyone else has any shoot 'em my way. I'm running late on the app, so I might have to just drop the cache part (which I don't want to do).

Thanks, ~Jeremy

8

Hi,

Jeremy Woertink wrote:

Ok, So, I'm a bad developer and have never used any sort of cacheing before. I decided it's time I step up and I threw in some memcached magic. I'm still pretty new to all this, so I'm confused on how some things work. I've watched the railscast on cacheing, and gone through many tutorials.

So, the problem I'm having is that I have this page being cached, and it's not updating the page when I do any sort of CRUD action on the model primarily used on this page.

Here is what I have

class SiteController < ApplicationController   caches_action :index

  def index     #this in my home page   end en

class ListingsController < SiteController   #This is the page being cached   def index     @listings = Listing.all   end end

class ListingSweeper < ActionController::Caching::Sweeper   observe Listing

  def after_save(listing)     expire_cache(listing)   end

  def after_update(listing)     expire_cache(listing)   end

  def after_destroy(listing)     expire_cache(listing)   end

  def expire_cache(listing)     expire_action root_path     expire_action listings_path   end

end

It seems to me that you miss to specify the cache sweeper in the controller. In your case, try to add this:

class SiteController < ApplicationController    caches_action :index    cache_sweeper :listing_sweeper

Regards,

.Viet Trung.