get calling cookbook within chef custom resource

I have a cookbook my_service with a custom resource write_config. This resource is called from another cookbook node_a.

my_service/resources/write_config.rb:

property :template_source, String, name_property: true 
property :calling_cookbook, String, required: true

action :create do
  template "/tmp/test.txt" do
    source   template_source
    cookbook calling_cookbook
    owner    'root'
    mode     '0644'
    action   :create
  end
end

Node cookbook recipe node_a/default.rb:

my_service_write_config 'config.erb' do
  calling_cookbook 'node_a'
end

This works fine, but I would like to get rid of the calling_cookbook property.

Is there a way to automatically get the calling_cookbook name?

Solution

(Thank you coderanger!) The basic resource template seems to get evaluated in the context of the calling (node_a) cookbook (?).

my_service/resources/write_config.rb:

property :template_source, String, name_property: true 
action :create do
  template "/tmp/test.txt" do
    source   template_source
    owner    'root'
    mode     '0644'
    action   :create
  end
end

Using it within the node cookbook recipe node_a/default.rb becomes a one-liner:
```
...
include_recipe 'my_service'
my_service_write_config 'config.erb'
...
```

Neat!

Solution

This is tracked automatically as new_resource.cookbook_name. You may need to to_s it because somehow it ends up a symbol sometimes but otherwise should be what you need.

Also specifically for templates this is already the default behavior if you just remove the cookbook line.