[chef] Notification on template change

[Steffen Gebert < >]

Hi list,

I'm searching for a way to notify another resource, as soon as a template 
changed:

template "foo.conf" do
  source "foo.conf.erb"
  notfies :run, "execute[rebuildConfig]"
end

(see this recipe [1]).

When using the create_if_missing action, it's only created once, but not as 
soon as I upload a cookbook with a changed version of the config file.
With the create action, the resource is notified every time (which flushes 
caches, regenerates merged config files etc..).

Is there a way in between? Notify, if the old and the new file differ?

Thanks for your help!
Steffen

[1] 
https://github.com/StephenKing/chef-cookbook-otrs/blob/master/recipes/default.rb#L175

P.S: It would be great, if one wants to review the OTRS cookbook - it still 
has some minor issues (and probably misses some best-practices)