[chef] Re: Re: Re: Re: Re: Re: How do I test an attribute value in an

[Tim Diggins < >]

You can access node attributes in recipes using

node["apache"] # preferred

node[:apache]  # as a symbol, deprecated

node.apache # as a method, deprecated

which works for sub-keys too:

node["apache"]["dir"]

node[:apache][:dir]

node.apache.dir

and test if there is such a attribute using 

node.attribute?("apache")

and 

node.apache.attribute?("dir") 

QUESTION: I suppose that one is a bit deprecated (despite being from the wiki) - should really be: 

node["apache"].attribute?("dir")

Ruby note:

In ruby predicate methods (which test whether something is true or not) often (by convention) end in '?' (like File.exists?() for example))

You might want to check out:

http://wiki.opscode.com/display/chef/Recipes#Recipes-AccessingNodeAttributes

and

http://wiki.opscode.com/display/chef/Attributes#Attributes-CookbookAttributeMethods

Another valuable page is http://wiki.opscode.com/display/chef/Just+Enough+Ruby+for+Chef

Tim

On Mon, Jun 27, 2011 at 9:29 AM, ItsMikeE < "> > wrote:

Thanks for the response
That helps, but still leaves me with some questions

Looking at the wiki page on setting attributes

Default in ../cookbooks/../attributes/default.rb
Example Precedence #1
default["apache"]["dir"] = "/etc/apache2"

Override in .../roles/rolename.rb
Example Precedence #8
override_attributes({ "apache" => {"dir" => "/etc/apache2"}})

How do I reference the attribute inside a recipe?
I don't mind if it is in a case statement, and if statement or an only_if. I am
just trying to choose between one of two source files to overwrite one
destination file.

Again going back to the wiki I can see
if node.chef.attribute?("webui_enabled")
 # set up webui stuff
end

How does that equate to the attributes that were set above?
Is it:
if node.apache.dir?
or
if node.chef.attribute?("apache""dir")
or
something else completely?


I don't really mind if it is in an only_if, or a case statement or an if test.