lib/ohai/system.rb in ohai-0.3.6 vs lib/ohai/system.rb in ohai-0.4.0

@@ -4,13 +4,13 @@
 # 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.
@@ -35,50 +35,49 @@
 end
 
 module Ohai
   class System
     attr_accessor :data, :seen_plugins
-    
+
     include Ohai::Mixin::FromFile
     include Ohai::Mixin::Command
-    
+
     def initialize
       @data = Mash.new
       @seen_plugins = Hash.new
       @providers = Mash.new
       @plugin_path = ""
-      Ohai::Log.level(Ohai::Config.log_level) 
     end
-    
+
     def [](key)
       @data[key]
     end
-    
+
     def []=(key, value)
       @data[key] = value
     end
-    
+
     def each(&block)
       @data.each do |key, value|
         block.call(key, value)
       end
     end
-    
+
     def attribute?(name)
-      @data.has_key?(name) 
+      @data.has_key?(name)
     end
-    
+
     def set(name, *value)
       set_attribute(name, *value)
     end
-    
+
     def from(cmd)
       status, stdout, stderr = run_command(:command => cmd)
-      return "" if stdout.nil?
+      return "" if stdout.nil? || stdout.empty?
       stdout.chomp!.strip
     end
-    
+
     def provides(*paths)
       paths.each do |path|
         parts = path.split('/')
         h = @providers
         unless parts.length == 0
@@ -90,38 +89,38 @@
         end
         h[:_providers] ||= []
         h[:_providers] << @plugin_path
       end
     end
-    
+
     # Set the value equal to the stdout of the command, plus run through a regex - the first piece of match data is the value.
     def from_with_regex(cmd, *regex_list)
       regex_list.flatten.each do |regex|
         status, stdout, stderr = run_command(:command => cmd)
-        return "" if stdout.nil?
+        return "" if stdout.nil? || stdout.empty?
         stdout.chomp!.strip
         md = stdout.match(regex)
         return md[1]
       end
     end
-    
+
     def set_attribute(name, *value)
       @data[name] = *value
       @data[name]
     end
-    
+
     def get_attribute(name)
       @data[name]
     end
-    
+
     def all_plugins
       require_plugin('os')
-      
+
       Ohai::Config[:plugin_path].each do |path|
-        [ 
-          Dir[File.join(path, '*')], 
-          Dir[File.join(path, @data[:os], '**', '*')] 
+        [
+          Dir[File.join(path, '*')],
+          Dir[File.join(path, @data[:os], '**', '*')]
         ].flatten.each do |file|
           file_regex = Regexp.new("#{path}#{File::SEPARATOR}(.+).rb$")
           md = file_regex.match(file)
           if md
             plugin_name = md[1].gsub(File::SEPARATOR, "::")
@@ -144,11 +143,11 @@
       else
         refreshments << providers
       end
       refreshments.flatten.uniq
     end
-    
+
     def refresh_plugins(path = '/')
       parts = path.split('/')
       if parts.length == 0
         h = @providers
       else
@@ -160,28 +159,28 @@
         end
       end
 
       refreshments = collect_providers(h)
       Ohai::Log.debug("Refreshing plugins: #{refreshments.join(", ")}")
-      
+
       refreshments.each do |r|
         @seen_plugins.delete(r) if @seen_plugins.has_key?(r)
       end
       refreshments.each do |r|
-        require_plugin(r) unless @seen_plugins.has_key?(r)        
+        require_plugin(r) unless @seen_plugins.has_key?(r)
       end
     end
-    
+
     def require_plugin(plugin_name, force=false)
       unless force
         return true if @seen_plugins[plugin_name]
       end
-      
+
       @plugin_path = plugin_name
-      
+
       filename = "#{plugin_name.gsub("::", File::SEPARATOR)}.rb"
-            
+
       Ohai::Config[:plugin_path].each do |path|
         check_path = File.expand_path(File.join(path, filename))
         begin
           @seen_plugins[plugin_name] = true
           Ohai::Log.debug("Loading plugin #{plugin_name}")
@@ -192,46 +191,55 @@
         rescue Exception,Errno::ENOENT => e
           Ohai::Log.debug("Plugin #{plugin_name} threw exception #{e.inspect}")
         end
       end
     end
-    
+
     # Sneaky!  Lets us stub out require_plugin when testing plugins, but still
     # call the real require_plugin to kick the whole thing off.
     alias :_require_plugin :require_plugin
-    
-    # Serialize this object as a hash 
+
+    # Serialize this object as a hash
     def to_json(*a)
       output = @data.clone
       output["json_class"] = self.class.name
       output.to_json(*a)
     end
-    
-    # Pretty Print this object as JSON 
+
+    # Pretty Print this object as JSON
     def json_pretty_print
       JSON.pretty_generate(@data)
     end
-    
+
     def attributes_print(a)
-      JSON.pretty_generate(@data[a])
+      raise ArgumentError, "I cannot find an attribute named #{a}!" unless @data.has_key?(a)
+      case a
+      when Hash,Mash,Array
+        JSON.pretty_generate(@data[a])
+      when String
+        JSON.pretty_generate(@data[a].to_a)
+      else
+        raise ArgumentError, "I can only generate JSON for Hashes, Mashes, Arrays and Strings. You fed me a #{@data[a].class}!"
+      end
     end
+
     # Create an Ohai::System from JSON
     def self.json_create(o)
       ohai = new
       o.each do |key, value|
         ohai.data[key] = value unless key == "json_class"
       end
       ohai
     end
-    
+
     def method_missing(name, *args)
-      return get_attribute(name) if args.length == 0 
-      
+      return get_attribute(name) if args.length == 0
+
       set_attribute(name, *args)
     end
-    
+
     private
       def load_plugin_file
-        
+
       end
   end
 end