Target mode for systemd service helper

Makes it so that local cookbook can bounce a remote service over
train/ssh/whatever.  Works at least for ubuntu.

Introduces a fairly rudimentary TrainHelpers class, using some
inspiration from ohbye.

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

6 files changed, 65 insertions, 19 deletions

diff --git a/lib/chef/mixin/shell_out.rb b/lib/chef/mixin/shell_out.rb
index 6c2db85dfe..9f7b18eace 100644
--- a/lib/chef/mixin/shell_out.rb
+++ b/lib/chef/mixin/shell_out.rb
@@ -17,7 +17,6 @@
 
 require "mixlib/shellout" unless defined?(Mixlib::ShellOut::DEFAULT_READ_TIMEOUT)
 require_relative "path_sanity"
-require "shellwords" unless defined?(Shellwords)
 
 class Chef
   module Mixin
@@ -160,7 +159,7 @@ class Chef
 
       def self.shell_out_command(*args, **options)
         if Chef::Config.target_mode?
-          FakeShellOut.new(args, options, transport_connection.run_command(Shellwords.join(" "))) # FIXME: train should accept run_command(*args)
+          FakeShellOut.new(args, options, transport_connection.run_command(args.join(" "))) # FIXME: train should accept run_command(*args)
         else
           cmd = if options.empty?
                   Mixlib::ShellOut.new(*args)
diff --git a/lib/chef/mixin/train_helpers.rb b/lib/chef/mixin/train_helpers.rb
new file mode 100644
index 0000000000..b37511bdea
--- /dev/null
+++ b/lib/chef/mixin/train_helpers.rb
@@ -0,0 +1,44 @@
+#--
+# Author:: Lamont Granquist <lamont@chef.io>
+# Copyright:: Copyright 2010-2018, Chef Software Inc.
+# License:: Apache License, Version 2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require "stringio" unless defined?(StringIO)
+
+class Chef
+  module Mixin
+    module TrainHelpers
+      def file_exist?(*args)
+        if Chef::Config.target_mode?
+          Chef.run_context.transport_connection.file(args[0]).exist?
+        else
+          File.exist?(*args)
+        end
+      end
+
+      # XXX: modifications to the StringIO won't get written back
+      def file_open(*args, &block)
+        if Chef::Config.target_mode?
+          content = Chef.run_context.transport_connection.file(args[0]).content
+          string_io = StringIO.new content
+          yield string_io if block_given?
+          string_io
+        else
+          File.open(*args, &block)
+        end
+      end
+    end
+  end
+end
diff --git a/lib/chef/node_map.rb b/lib/chef/node_map.rb
index 01f9d215cb..f54b3dc6bb 100644
--- a/lib/chef/node_map.rb
+++ b/lib/chef/node_map.rb
@@ -287,8 +287,6 @@ class Chef
     # "provides" lines with identical filters sort by class name (ascending).
     #
     def compare_matchers(key, new_matcher, matcher)
-      cmp = compare_matcher_properties(new_matcher[:target_mode], matcher[:target_mode])
-      return cmp if cmp != 0
       cmp = compare_matcher_properties(new_matcher[:block], matcher[:block])
       return cmp if cmp != 0
       cmp = compare_matcher_properties(new_matcher[:platform_version], matcher[:platform_version])
diff --git a/lib/chef/platform/service_helpers.rb b/lib/chef/platform/service_helpers.rb
index c469b3fe62..2faec6fc8a 100644
--- a/lib/chef/platform/service_helpers.rb
+++ b/lib/chef/platform/service_helpers.rb
@@ -17,11 +17,14 @@
 #
 
 require_relative "../chef_class"
+require_relative "../mixin/train_helpers"
 
 class Chef
   class Platform
     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
@@ -38,19 +41,19 @@ class Chef
         def service_resource_providers
           providers = []
 
-          if ::File.exist?(Chef.path_to("/usr/sbin/update-rc.d"))
+          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"))
+          if file_exist?(Chef.path_to("/usr/sbin/invoke-rc.d"))
             providers << :invokercd
           end
 
-          if ::File.exist?(Chef.path_to("/sbin/initctl"))
+          if file_exist?(Chef.path_to("/sbin/initctl"))
             providers << :upstart
           end
 
-          if ::File.exist?(Chef.path_to("/sbin/insserv"))
+          if file_exist?(Chef.path_to("/sbin/insserv"))
             providers << :insserv
           end
 
@@ -58,7 +61,7 @@ class Chef
             providers << :systemd
           end
 
-          if ::File.exist?(Chef.path_to("/sbin/chkconfig"))
+          if file_exist?(Chef.path_to("/sbin/chkconfig"))
             providers << :redhat
           end
 
@@ -68,23 +71,23 @@ class Chef
         def config_for_service(service_name)
           configs = []
 
-          if ::File.exist?(Chef.path_to("/etc/init.d/#{service_name}"))
+          if file_exist?(Chef.path_to("/etc/init.d/#{service_name}"))
             configs += [ :initd, :systemd ]
           end
 
-          if ::File.exist?(Chef.path_to("/etc/init/#{service_name}.conf"))
+          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}"))
+          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}"))
+          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}"))
+          if file_exist?(Chef.path_to("/usr/local/etc/rc.d/#{service_name}"))
             configs << :usr_local_etc_rcd
           end
 
@@ -98,13 +101,13 @@ class Chef
         private
 
         def systemd_is_init?
-          ::File.exist?(Chef.path_to("/proc/1/comm")) &&
-            ::File.open(Chef.path_to("/proc/1/comm")).gets.chomp == "systemd"
+          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?(
+            file_exist?(
               Chef.path_to("#{load_path}/systemd/system/#{svc_name.gsub(/@.*$/, '@')}.service")
             )
           end
@@ -113,7 +116,7 @@ class Chef
         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}"))
+            file_exist?(Chef.path_to("#{load_path}/systemd/system/#{svc_name}"))
           end
         end
       end
diff --git a/lib/chef/provider/service/systemd.rb b/lib/chef/provider/service/systemd.rb
index 4cb564e8c0..46541bac73 100644
--- a/lib/chef/provider/service/systemd.rb
+++ b/lib/chef/provider/service/systemd.rb
@@ -26,7 +26,7 @@ class Chef::Provider::Service::Systemd < Chef::Provider::Service::Simple
 
   include Chef::Mixin::Which
 
-  provides :service, os: "linux" do |node|
+  provides :service, os: "linux", target_mode: true do |node|
     Chef::Platform::ServiceHelpers.service_resource_providers.include?(:systemd)
   end
 
@@ -77,6 +77,7 @@ class Chef::Provider::Service::Systemd < Chef::Provider::Service::Simple
 
   def get_systemctl_options_args
     if new_resource.user
+      raise NotImplementedError, "#{new_resource} does not support the user property on a target_mode host (yet)" if Chef::Config.target_mode?
       uid = Etc.getpwnam(new_resource.user).uid
       options = {
         environment: {
diff --git a/lib/chef/resource/service.rb b/lib/chef/resource/service.rb
index e13f237481..508ef8e643 100644
--- a/lib/chef/resource/service.rb
+++ b/lib/chef/resource/service.rb
@@ -24,6 +24,7 @@ require_relative "../dist"
 class Chef
   class Resource
     class Service < Chef::Resource
+      provides :service, target_mode: true
       identity_attr :service_name
 
       description "Use the service resource to manage a service."