Don't log the agent configuration changes (#274)

* Don't log the agent configuration changes

This will work on any Chef Client 11.14+ by suppressing the diff output in the logs to prevent API credentials from leaking into logs

* Use better feature detection

This feature was introduced with Chef 11.14 so we're checking the resource instance methods since it was added to the File, Template, and Execute resources.

* Apply sensitive to the datadog_monitor resource

providers/monitor.rb

@@ -23,6 +23,7 @@ def whyrun_supported?
       :instances   => new_resource.instances
     )
     cookbook new_resource.cookbook
+    sensitive true if Chef::Resource.instance_methods(false).include?(:sensitive)
     notifies :restart, 'service[datadog-agent]', :delayed if node['datadog']['agent_start']
   end
 
@@ -36,6 +37,7 @@ def whyrun_supported?
   Chef::Log.debug "Removing #{new_resource.name} from #{confd_dir}"
   file ::File.join(confd_dir, "#{new_resource.name}.yaml") do
     action :delete
+    sensitive true if Chef::Resource.instance_methods(false).include?(:sensitive)
     notifies :restart, 'service[datadog-agent]', :delayed if node['datadog']['agent_start']
   end
 

recipes/dd-agent.rb

@@ -63,6 +63,7 @@
     :api_key => node['datadog']['api_key'],
     :dd_url => node['datadog']['url']
   )
+  sensitive true if Chef::Resource.instance_methods(false).include?(:sensitive)
 end
 
 # Common configuration