[chef] Wrapper Cookbooks and Computed Attributes

[Justin Locsei < >]

I'm sure that I'm missing something very simple and self-evident, but I'm at a
bit of a loss as to how to handle computed attributes using override 
statements
in wrapper cookbooks.  I'm trying to follow what seems like the advice of the
wise men of Chef and use versioned wrapper cookbooks instead of roles, but
doing so seems like it involves sacrificing the ability to override a default
attribute for a cookbook and have that overridden default value be used in
computing other attributes.

For example, say I have a cookbook called "example".  In its
attributes/default.rb file, it has these two lines:

default['example']['version'] = '1.0'
default['example']['module'] = "example-#{example['version']}"

By default, the value of node['example']['module'] should be properly set to
"example-1.0".  If I set the version to "1.1" using a role, I can access
node['example']['module'] in a recipe, and its value should be "example-1.1",
which is great.  However, if I set up a wrapper cookbook named
"mycompany-example" and have its attributes/default.rb file contain the line
"override['example']['version'] = '1.1'", accessing node['example']['module']
in a recipe will give me a value of "example-1.0", even though accessing
node['example']['version'] would correctly be '1.1'.  The ideal outcome would
be to have the module value be "example-1.1", and I'm lost as to how to make
that happen.

If I'm reading the docs properly, it seems like attribute files are evaluated
in runlist order, so I imagine it'd be possible to just have
"mycompany-example" in the runlist, with no mention of the "example" cookbook,
and then add an "include_attribute 'example'" line after the override in the
attributes file.  However, the docs also say that dependencies specified in
metadata are loaded before the cookbook that depends on them, and I have the
"example" cookbook specified as a dependency in the "mycompany-example"
cookbook's metadata.rb, making it so that the "example" cookbook's attributes
file has already been loaded by the time I try to override an attribute that 
it
uses to compute other attributes.  I suppose I could remove that dependency,
but that seems wrong.  

Does anyone have any experience with problems like this?  Any suggestions, 
even
if they're to throw out this approach and go with something different, would 
be
greatly appreciated.