WIP: Add the ability to list pluginslist_plugins_feature

Signed-off-by: Tim Smith <tsmith@chef.io>

4 files changed, 46 insertions, 1 deletions

diff --git a/lib/ohai/application.rb b/lib/ohai/application.rb
index b1455cab..12acd452 100644
--- a/lib/ohai/application.rb
+++ b/lib/ohai/application.rb
@@ -56,6 +56,12 @@ class Ohai::Application
     description: "Set the log file location, defaults to STDOUT - recommended for daemonizing",
     proc: nil
 
+  option :print_plugins,
+    short: "-p",
+    long: "--print-plugins",
+    description: "Print information on each available plugin",
+    boolean: true
+
   option :help,
     short: "-h",
     long: "--help",
@@ -79,7 +85,11 @@ class Ohai::Application
   def run
     elapsed = Benchmark.measure do
       configure_ohai
-      run_application
+      if config[:print_plugins]
+        run_print_plugins
+      else
+        run_application
+      end
     end
     Ohai::Log.debug("Ohai took #{elapsed.total} total seconds to run.")
   end
@@ -88,6 +98,8 @@ class Ohai::Application
   #
   # @return void
   def configure_ohai
+    # @attributes receives all the attribute names passed on the CLI and we use
+    # it later to pass in the list of attributes to filter
     @attributes = parse_options
     @attributes = nil if @attributes.empty?
 
@@ -115,6 +127,14 @@ class Ohai::Application
     end
   end
 
+  def run_print_plugins
+    config[:invoked_from_cli] = true
+    config[:logger] = Ohai::Log.with_child
+    ohai = Ohai::System.new(config)
+    require 'pry'; binding.pry
+    ohai.list_plugins(@attributes)
+  end
+
   class << self
     # Log a fatal error message to both STDERR and the Logger, exit the application
     # @param msg [String] the message to log
diff --git a/lib/ohai/dsl/plugin/versionvii.rb b/lib/ohai/dsl/plugin/versionvii.rb
index 3a8c904e..dc7d5576 100644
--- a/lib/ohai/dsl/plugin/versionvii.rb
+++ b/lib/ohai/dsl/plugin/versionvii.rb
@@ -101,6 +101,10 @@ module Ohai
           !!@optional
         end
 
+        def self.description(text)
+          @description = text
+        end
+
         # define data collection methodology per platform
         #
         # @param platform [Symbol] the platform to collect data for
diff --git a/lib/ohai/plugins/aix/kernel.rb b/lib/ohai/plugins/aix/kernel.rb
index 39f18c5e..0af4409d 100644
--- a/lib/ohai/plugins/aix/kernel.rb
+++ b/lib/ohai/plugins/aix/kernel.rb
@@ -20,6 +20,8 @@
 Ohai.plugin(:Kernel) do
   provides "kernel", "kernel/modules"
 
+  description "This gathers data on the kernel such as its version and modules"
+
   collect_data(:aix) do
     kernel Mash.new
 
diff --git a/lib/ohai/system.rb b/lib/ohai/system.rb
index 6c920408..6d3c3328 100644
--- a/lib/ohai/system.rb
+++ b/lib/ohai/system.rb
@@ -130,6 +130,25 @@ module Ohai
       freeze_strings!
     end
 
+    def list_plugins(attribute_filter = nil)
+      reset_system
+      load_plugins
+      plugins = {}
+      begin
+        @provides_map.all_plugins(attribute_filter).each do |plugin|
+          #require 'pry';binding.pry
+          plugins[plugin.name] = {}
+          plugins[plugin.name][:optional] = plugin.optional?
+          plugins[plugin.name][:dependencies] = plugin.dependencies
+          plugins[plugin.name][:description] = plugin.description
+        end
+      rescue Ohai::Exceptions::AttributeNotFound, Ohai::Exceptions::DependencyCycle => e
+        logger.error("Encountered error while running plugins: #{e.inspect}")
+        raise
+      end
+      plugins
+    end
+
     def run_additional_plugins(plugin_path)
       @loader.load_additional(plugin_path).each do |plugin|
         logger.trace "Running plugin #{plugin}"