class Foo < ActiveRecord::Base
  serialize :bar
end

In this instance, assume an object of type “Bar” is what’s being serialized. After save, the data appears fine, but when you retrieve the data, instead of your Object you end up with yaml that looks like this:

[#<YAML::Object:0x3fcade8 @ivars={"attributes_cache"=>{}, "attributes"=>{"updated_at"=>"2008-11-04 19:33:05", "id"=>"1", "message"=>"Hello World!", "created_at"=>"2008-11-04 19:33:05"}}, @class="Bar">

This most likely means that the model of the object being serialized is not loaded yet. This can be resolved by simply doing:

class Foo < ActiveRecord::Base
  Bar

  serialize :bar
end

This will load the model before serialization occurs and you’ll be all set.

While trying to figure out what was going on, a couple of things became apparent. If I moved tests around or deleted specific tests (mainly update and destroy tests), it caused previously failing tests to pass. Also, setting “self.use_transactional_fixtures” to false in “test_helper.rb” caused most tests to pass. As I was checking on that further in one of my apps (one that I didn’t delete all the comments from), I noticed this:

“Every Active Record database supports transactions except MyISAM tables in MySQL.  Turn off transactional fixtures in this case; however, if you don’t care one way or the other, switching from MyISAM to InnoDB tables is recommended.”

Cue the lightbulb.

Jumping into mysql and running “show engines;” confirmed the bulb. InnoDB was disabled. So now we ned to remedy this little problem.

If you already have a ‘my.cnf’ file, you’re ahead of the class, so please hold on while the rest of us catch up.

The MySQL package installer drops mysql in:

/usr/local/mysql

If you look in the support-files directory, they have several my.cnf sample files. So now we need to get one of these into play.

Copy

/usr/local/mysql/support-files/my-medium.cnf

to

/etc/my.cnf

At this time I’d like to welcome back those of you who already had a my.cnf file.

Now open your my.cnf file and uncomment the lines that start with “innodb_” (starting at line 123 in my config file). Save the file and restart MySQL. If you go back into mysql and rerun “show engines;”, you should now see InnoDB support has been enabled.

Now when you run your tests, all should be well in the world again.

You can comment out ERb delimiters in your view by adding a pound sign before the equal sign.

<%#= str %>

When rendering a collection, you have access to a zero-based “partial_counter” variable that increments on each iteration.

<%= div_for(entry) do %>
	<%= entry_counter %>
<% end  %>

Todays lesson brought you by chapter 10 of “The Rails Way” by Obie Fernandez.

The folks over at Rails for PHP Developers have a pretty good start on content, especially for Array, String and Filesystem functions. The feature I was planning on, which I am not seeing their site, is a way for the community to contribute. Even if it were heavily moderated, I think it would be a boon for the site to flesh out its reference much more quickly.