Add chef-utils gem with various recipe DSL helpers

This is the implementation of [RFC-087](https://github.com/chef-boneyard/chef-rfc/blob/master/rfc087-distro-sugar-helpers.md)
although some of the specifics have been iterated on and changed.

The documentation will be in the [README.md](https://github.com/chef/chef/tree/master/chef-utils/README.md) once this is merged.

While this PR mostly moves chef-sugar utilities into core-chef via this chef-utils gem, the scope of the chef-utils gem
should be considered larger than just that. As an example this PR moves the Mash class into this gem for reuse in ohai
as well.

Signed-off-by: Lamont Granquist <lamont@scriptkiddie.org>

3 files changed, 19 insertions, 88 deletions

diff --git a/lib/chef/platform/query_helpers.rb b/lib/chef/platform/query_helpers.rb
index ffcd7e0bd9..3cce4b5d2c 100644
--- a/lib/chef/platform/query_helpers.rb
+++ b/lib/chef/platform/query_helpers.rb
@@ -1,6 +1,6 @@
 #
 # Author:: Adam Jacob (<adam@chef.io>)
-# Copyright:: Copyright 2008-2016, Chef Software Inc.
+# Copyright:: Copyright 2008-2019, Chef Software Inc.
 # License:: Apache License, Version 2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -16,12 +16,14 @@
 # limitations under the License.
 #
 
+require "chef-utils" unless defined?(ChefUtils::CANARY)
+
 class Chef
   class Platform
 
     class << self
       def windows?
-        ChefConfig.windows?
+        ChefUtils.windows?
       end
 
       def windows_nano_server?
diff --git a/lib/chef/platform/rebooter.rb b/lib/chef/platform/rebooter.rb
index ad17ffad8c..c3378e6313 100644
--- a/lib/chef/platform/rebooter.rb
+++ b/lib/chef/platform/rebooter.rb
@@ -35,7 +35,7 @@ class Chef
           reboot_info = node.run_context.reboot_info
 
           cmd = case
-                when Chef::Platform.windows?
+                when ChefUtils.windows?
                   # should this do /f as well? do we then need a minimum delay to let apps quit?
                   # Use explicit path to shutdown.exe, to protect against https://github.com/chef/chef/issues/5594
                   windows_shutdown_path = "#{ENV["SYSTEMROOT"]}/System32/shutdown.exe"
diff --git a/lib/chef/platform/service_helpers.rb b/lib/chef/platform/service_helpers.rb
index 851c3ebffc..a97a6f2ef4 100644
--- a/lib/chef/platform/service_helpers.rb
+++ b/lib/chef/platform/service_helpers.rb
@@ -1,6 +1,6 @@
 #
 # Author:: Lamont Granquist (<lamont@chef.io>)
-# Copyright:: Copyright 2014-2016, Chef Software, Inc.
+# Copyright:: Copyright 2014-2019, Chef Software Inc.
 # License:: Apache License, Version 2.0
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
@@ -17,53 +17,22 @@
 #
 
 require_relative "../chef_class"
-require_relative "../mixin/train_helpers"
+require "chef-utils" if defined?(ChefUtils::CANARY)
 
 class Chef
   class Platform
+    # @deprecated, use ChefUtils::DSL::Service instead (via the ChefUtils Universal DSL)
     class ServiceHelpers
       class << self
-        include Chef::Mixin::TrainHelpers
-
-        # This helper is mostly used to sort out the mess of different
-        # linux mechanisms that can be used to start services.  It does
-        # not necessarily need to linux-specific, but currently all our
-        # other service providers are narrowly platform-specific with no
-        # alternatives.
-        #
-        # NOTE: if a system has (for example) chkconfig installed then we
-        # should report that chkconfig is installed.  The fact that a system
-        # may also have systemd installed does not mean that we do not
-        # report that systemd is also installed.  This module is purely for
-        # discovery of all the alternatives, handling the priority of the
-        # different services is NOT a design concern of this module.
-        #
         def service_resource_providers
           providers = []
 
-          if file_exist?(Chef.path_to("/usr/sbin/update-rc.d"))
-            providers << :debian
-          end
-
-          if file_exist?(Chef.path_to("/usr/sbin/invoke-rc.d"))
-            providers << :invokercd
-          end
-
-          if file_exist?(Chef.path_to("/sbin/initctl"))
-            providers << :upstart
-          end
-
-          if file_exist?(Chef.path_to("/sbin/insserv"))
-            providers << :insserv
-          end
-
-          if systemd_is_init?
-            providers << :systemd
-          end
-
-          if file_exist?(Chef.path_to("/sbin/chkconfig"))
-            providers << :redhat
-          end
+          providers << :debian if ChefUtils::DSL::Service.debianrcd?
+          providers << :invokercd if ChefUtils::DSL::Service.invokercd?
+          providers << :upstart if ChefUtils::DSL::Service.upstart?
+          providers << :insserv if ChefUtils::DSL::Service.insserv?
+          providers << :systemd if ChefUtils.systemd?
+          providers << :redhat if ChefUtils::DSL::Service.redhatrcd?
 
           providers
         end
@@ -71,54 +40,14 @@ class Chef
         def config_for_service(service_name)
           configs = []
 
-          if file_exist?(Chef.path_to("/etc/init.d/#{service_name}"))
-            configs += %i{initd systemd}
-          end
-
-          if file_exist?(Chef.path_to("/etc/init/#{service_name}.conf"))
-            configs << :upstart
-          end
-
-          if file_exist?(Chef.path_to("/etc/xinetd.d/#{service_name}"))
-            configs << :xinetd
-          end
-
-          if file_exist?(Chef.path_to("/etc/rc.d/#{service_name}"))
-            configs << :etc_rcd
-          end
-
-          if file_exist?(Chef.path_to("/usr/local/etc/rc.d/#{service_name}"))
-            configs << :usr_local_etc_rcd
-          end
-
-          if has_systemd_service_unit?(service_name) || has_systemd_unit?(service_name)
-            configs << :systemd
-          end
+          configs << :initd if ChefUtils::DSL::Service.service_script_exist?(:initd, service_name)
+          configs << :upstart if ChefUtils::DSL::Service.service_script_exist?(:upstart, service_name)
+          configs << :xinetd if ChefUtils::DSL::Service.service_script_exist?(:xinetd, service_name)
+          configs << :systemd if ChefUtils::DSL::Service.service_script_exist?(:systemd, service_name)
+          configs << :etc_rcd if ChefUtils::DSL::Service.service_script_exist?(:etc_rcd, service_name)
 
           configs
         end
-
-        private
-
-        def systemd_is_init?
-          file_exist?(Chef.path_to("/proc/1/comm")) &&
-            file_open(Chef.path_to("/proc/1/comm")).gets.chomp == "systemd"
-        end
-
-        def has_systemd_service_unit?(svc_name)
-          %w{ /etc /usr/lib /lib /run }.any? do |load_path|
-            file_exist?(
-              Chef.path_to("#{load_path}/systemd/system/#{svc_name.gsub(/@.*$/, "@")}.service")
-            )
-          end
-        end
-
-        def has_systemd_unit?(svc_name)
-          # TODO: stop supporting non-service units with service resource
-          %w{ /etc /usr/lib /lib /run }.any? do |load_path|
-            file_exist?(Chef.path_to("#{load_path}/systemd/system/#{svc_name}"))
-          end
-        end
       end
     end
   end