Plugin_path configuration issue with custom plugins

[Baptiste Courtois]

Cookbook version

= 4.0

Chef-client version

12.8

Platform Details

CentOS 7.2 / Windows Server 2012R2

Scenario:

I'm trying to define an ohai plugin, but also use its values in my attributes file.

Steps to Reproduce:

my_cookbook/attributes/default.rb

default['my_cookbook'] # autovivify
if node['my_cookbook']['ohai']
  default['my_cookbook']['ohai']['ultra_important_attribute'] = 'OK'
else
  ::Chef::Log.warn 'my_cookbook.ohai is not available, maybe next run?'
end

my_cookbook/recipes/default.rb

ohai_plugin 'my_custom_plugin'

my_cookbook/files/default/my_custom_plugin.rb

Ohai.plugin(:MyCookbookOhai) do
  provides 'my_cookbook/ohai/ultra_important_attribute'
  collect_data do
    my_cookbook['ohai'] = Mash.new(ultra_important_attribute: :ultra_important)
  end
end

Expected Result:

At first run I expect to get the unavailable warning; but at 2nd run I should normally have access to my ultra important attribute.

Actual Result:

Even using the compile_time property of the ohai_plugin resource, my attribute is not accessible from attributes file.

       [2016-12-07T16:07:02+00:00] WARN: my_cookbook.ohai is not available, maybe next run?
       Recipe: my_cookbook::default
         * ohai_plugin[my_custom_plugin] action create
       [2016-12-07T16:07:02+00:00] WARN: The Ohai plugin_path does not include /tmp/kitchen/ohai/plugins. Ohai will reload on each chef-client run in order to add this directory to the path unless you modify your client.rb configuration to add this directory to plugin_path. The plugin_path can be set via the chef-client::config recipe. See 'Ohai Settings' at https://docs.chef.io/config_rb_client.html#ohai-settings for more details.
       [2016-12-07T16:07:02+00:00] WARN: Adding /tmp/kitchen/ohai/plugins to the Ohai plugin path for this chef-client run only

I know that I'm able to change the ohai.plugin path using chef-client cookbook, but a simple cookbook maintainer I don't want to change my user's configuration.

What do you suggest?
IMHO the present ohai cookbook should be responsible of Ohai configuration see chef/ohai#919

Regards.

Cc. @aboten

[Seth Thomas]

Pretty sure there isn't anything unexpected here - if the attribute check is moved into the recipe as opposed to the attributes I'm pretty sure you'd get the desired effect. Try that and let us know - at least as I read this there isn't anything wrong so much as the order of operations should simply be changed.

[Baptiste Courtois]

Thanks for your suggestion, it surely "works", but this is not the described scenario ... I want to use my attribute in the attribute file. I don't want to move it to the recipe, I want the ohai attributes available in attributes phase, which seems to me normal.
For me, attributes files are here to compute attributes at certain time in the process, I don't want to compute my attributes in recipes, otherwise it breaks the flow, and the cookbook depending on me won't be able to rely on my attributes.

To rephrase my question:

I want to have access to custom ohai plugin's attributes inside attributes file; is there any other way than changing the Ohai::plugin_path using the chef-client cookbook?

[Jennifer Davis]

What do you mean by the "attributes phase"? This cookbook isn't going to change how ohai works. The error you are pasting in here is around test kitchen + ohai.

[Baptiste Courtois]

@iennae the example I give you is a repro in kitchen yes.
When I talkk about attribute phase, I'm trying to name the phase when the attributes are compiled.

I'll try to explain in a different way, let's say cookbook B depends on an ohai attribute defined in cookbook A

1. ohai runs
2. A attributes are compiled
3. B attributes are compiled
   ... other stuffs are done
4. A recipe is included and compiled
5. B recipe is included and compiled

In this example, the "attribute phase" starts after 1. and ends before 4.
During this phase, because my ohai plugin is not in the plugin_path, it has not been loaded at step 1.
So in step 3. B attributes won't be able to compute a value based on the ohai plugin

Is it clearer this way?

[Michael Mol]

@Annih, if I understand the docs, you need to specify depends 'attributename' in ohai plugin you want to be able to consume an attribute within.

[Baptiste Courtois]

Thanks @mikemol for your answer, but in my case I'm not in a ohai plugin, I'm using the result of a plugin in attributes files.