Use Chef to check whether a package has been installed

gistfile1.txt

[root@ci cache]# chef-shell
loading configuration: none (standalone session)
Session type: standalone
Loading.done.

This is the chef-shell.
 Chef Version: 11.8.2
 http://www.opscode.com/chef
 http://wiki.opscode.com/display/chef/Home

run `help' for help, `exit' or ^D to quit.

Ohai2u [email protected]!
chef > recipe_mode
chef:recipe > echo off
chef:recipe > pkg = Chef::Resource::Package.new("chef")
chef:recipe > provider = Chef::Platform.find_provider_for_node(node, pkg).new(pkg, run_context)
chef:recipe > puts provider.load_current_resource.version
11.8.2-1.el6
chef:recipe >
chef:recipe > chef_svc = Chef::Resource::Service.new("chef-client")
chef:recipe > chef_svc_provider = Chef::Platform.find_provider_for_node(node, chef_svc).new(chef_svc, run_context)
chef:recipe > puts chef_svc_provider.load_current_resource.enabled
false
chef:recipe >
chef:recipe > cron_svc = Chef::Resource::Service.new("crond")
chef:recipe > cron_svc_provider = Chef::Platform.find_provider_for_node(node, cron_svc).new(cron_svc, run_context)
chef:recipe > puts cron_svc_provider.load_current_resource.enabled
true