Now, a Hash Poser is a class that acts and behaves exactly like a normal Hash. Let’s see his code:
Dead Simple, you can copy and paste this code to somewhere like ‘config/initializers/hash_poser.rb’. You can easily see how this can be used in your models:
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class Post < ActiveRecord::Base default_scope HashPoser.new do { :conditions => { :user_id => UserSession.find } } end end |
This is supposing you’re using something like Authlogic, but actually you will want something more like ‘Site.find’ or whatever. The point is, now whatever finder you were using throughout your application will have this conditions added to it. So, a simple ‘Post.all’, in this example, will automagically run:
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SELECT * FROM "users" WHERE ("users"."id" = 1)
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Considering that you’re not using something like ‘find_by_sql’ with hand crafted SQL queries, the ‘default_scope’ will override all your finders. Of course, it’s easier said than done, so have your test suite ready when you do this change. As I said, you will have to add a column like ‘site_id’ to every table you need to be multi-site.
I would like to see what other people think of this way of thinking and what caveats there are for this use case. Most of the time Rails apps will be stand-alone, but in a few exception cases, we really do want to have a single app serving multiple customers. What’s your take on this concept?