[OHAI-267] Reworked cloud file to be a more generic hint system

lib/ohai/config.rb

@@ -21,10 +21,23 @@
 module Ohai
   class Config
     extend Mixlib::Config
+
+    # from chef/config.rb, should maybe be moved to mixlib-config?
+    def self.platform_specific_path(path)
+      if RUBY_PLATFORM =~ /mswin|mingw|windows/
+        # turns /etc/chef/client.rb into C:/chef/client.rb
+        path = File.join(ENV['SYSTEMDRIVE'], path.split('/')[2..-1])
+        # ensure all forward slashes are backslashes
+        path.gsub!(File::SEPARATOR, (File::ALT_SEPARATOR || '\\'))
+      end
+      path
+    end
+
 
     log_level :info
     log_location STDOUT
     plugin_path [ File.expand_path(File.join(File.dirname(__FILE__), 'plugins'))]
     disabled_plugins []
+    hints_path [ platform_specific_path('/etc/chef/ohai/hints') ]
   end
 end

lib/ohai/plugins/ec2.rb

@@ -20,14 +20,12 @@
 provides "ec2"
 
 require 'ohai/mixin/ec2_metadata'
-require 'ohai/mixin/cloud'
 
 require_plugin "hostname"
 require_plugin "kernel"
 require_plugin "network"
 
 extend Ohai::Mixin::Ec2Metadata
-extend Ohai::Mixin::Cloud
 
 def has_ec2_mac?
   network[:interfaces].values.each do |iface|
@@ -45,7 +43,7 @@ def has_ec2_mac?
 def looks_like_ec2?
   # Try non-blocking connect so we don't "block" if 
   # the Xen environment is *not* EC2
-  cloud_file?('ec2') || has_ec2_mac? && can_metadata_connect?(EC2_METADATA_ADDR,80)
+  hint?('ec2') || has_ec2_mac? && can_metadata_connect?(EC2_METADATA_ADDR,80)
 end
 
 if looks_like_ec2?

lib/ohai/plugins/eucalyptus.rb

@@ -20,14 +20,12 @@
 provides "eucalyptus"
 
 require 'ohai/mixin/ec2_metadata'
-require 'ohai/mixin/cloud'
 
 require_plugin "hostname"
 require_plugin "kernel"
 require_plugin "network"
 
 extend Ohai::Mixin::Ec2Metadata
-extend Ohai::Mixin::Cloud
 
 def get_mac_address(addresses)
   detected_addresses = addresses.detect { |address, keypair| keypair == {"family"=>"lladdr"} }
@@ -52,7 +50,7 @@ def has_euca_mac?
 def looks_like_euca?
   # Try non-blocking connect so we don't "block" if 
   # the Xen environment is *not* EC2
-  cloud_file?('eucalyptus') || has_euca_mac? && can_metadata_connect?(EC2_METADATA_ADDR,80)
+  hint?('eucalyptus') || has_euca_mac? && can_metadata_connect?(EC2_METADATA_ADDR,80)
 end
 
 if looks_like_euca?

lib/ohai/plugins/rackspace.rb

@@ -16,13 +16,9 @@
 
 provides "rackspace"
 
-require 'ohai/mixin/cloud'
-
 require_plugin "kernel"
 require_plugin "network"
 
-extend Ohai::Mixin::Cloud
-
 # Checks for matching rackspace kernel name
 #
 # === Return
@@ -52,7 +48,7 @@ def has_rackspace_mac?
 # true:: If the rackspace cloud can be identified
 # false:: Otherwise
 def looks_like_rackspace?
-  cloud_file?('rackspace') || has_rackspace_mac? || has_rackspace_kernel?
+  hint?('rackspace') || has_rackspace_mac? || has_rackspace_kernel?
 end
 
 # Names rackspace ip address

lib/ohai/system.rb

@@ -26,7 +26,7 @@
 
 module Ohai
   class System
-    attr_accessor :data, :seen_plugins
+    attr_accessor :data, :seen_plugins, :hints
 
     include Ohai::Mixin::FromFile
     include Ohai::Mixin::Command
@@ -36,6 +36,7 @@ def initialize
       @seen_plugins = Hash.new
       @providers = Mash.new
       @plugin_path = ""
+      @hints = Hash.new
     end
 
     def [](key)
@@ -101,6 +102,27 @@ def set_attribute(name, *values)
     def get_attribute(name)
       @data[name]
     end
+
+    def hint?(name)
+      @json_parser ||= Yajl::Parser.new
+
+      return @hints[name] if @hints[name]
+
+      Ohai::Config[:hints_path].each do |path|
+        filename = File.join(path, "#{name}.json")
+        if File.exist?(filename)
+          begin
+            hash = @json_parser.parse(File.read(filename))
+            @hints[name] = hash || Hash.new # hint should exist because the file did, even if it didn't contain anything
+          rescue Yajl::ParseError => e
+            Ohai::Log.error("Could not parse hint file at #{filename}: #{e.message}")
+          end
+        end
+      end
+
+      @hints[name]
+    end
+
 
     def all_plugins
       require_plugin('os')
@@ -159,6 +181,9 @@ def refresh_plugins(path = '/')
 
       refreshments = collect_providers(h)
       Ohai::Log.debug("Refreshing plugins: #{refreshments.join(", ")}")
+
+      # remove the hints cache
+      @hints = Hash.new
 
       refreshments.each do |r|
         @seen_plugins.delete(r) if @seen_plugins.has_key?(r)

spec/ohai/plugins/ec2_spec.rb

@@ -90,25 +90,25 @@
     it_should_behave_like "ec2"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(true)
-      File.stub!(:read).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return('ec2')
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/ec2.json').and_return(true)
+      File.stub!(:read).with('/etc/chef/ohai/hints/ec2.json').and_return('')
     end
   end
 
   describe "without cloud file" do
     it_should_behave_like "!ec2"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(false)
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/ec2.json').and_return(false)
     end
   end
 
   describe "with rackspace cloud file" do
     it_should_behave_like "!ec2"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(true)
-      File.stub!(:read).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return('rackspace')
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/rackspace.json').and_return(true)
+      File.stub!(:read).with('/etc/chef/ohai/hints/rackspace.json').and_return('')
     end
   end
 

spec/ohai/plugins/eucalyptus_spec.rb

@@ -89,25 +89,25 @@
     it_should_behave_like "eucalyptus"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(true)
-      File.stub!(:read).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return('eucalyptus')
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/eucalyptus.json').and_return(true)
+      File.stub!(:read).with('/etc/chef/ohai/hints/eucalyptus.json').and_return('')
     end
   end
 
   describe "without cloud file" do
     it_should_behave_like "!eucalyptus"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(false)
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/eucalyptus.json').and_return(false)
     end
   end
 
-  describe "with rackspace cloud file" do
+  describe "with ec2 cloud file" do
     it_should_behave_like "!eucalyptus"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(true)
-      File.stub!(:read).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return('rackspace')
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/ec2.json').and_return(true)
+      File.stub!(:read).with('/etc/chef/ohai/hints/ec2.json').and_return('')
     end
   end
 

spec/ohai/plugins/rackspace_spec.rb

@@ -116,25 +116,25 @@
     it_should_behave_like "rackspace"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(true)
-      File.stub!(:read).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return("rackspace\n")
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/rackspace.json').and_return(true)
+      File.stub!(:read).with('/etc/chef/ohai/hints/rackspace.json').and_return('')
     end
   end
 
   describe "without cloud file" do
     it_should_behave_like "!rackspace"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(false)
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/rackspace.json').and_return(false)
     end
   end
 
   describe "with ec2 cloud file" do
     it_should_behave_like "!rackspace"
 
     before(:each) do
-      File.stub!(:exist?).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return(true)
-      File.stub!(:read).with(Ohai::Mixin::Cloud::CLOUD_FILE).and_return('ec2')
+      File.stub!(:exist?).with('/etc/chef/ohai/hints/ec2.json').and_return(true)
+      File.stub!(:read).with('/etc/chef/ohai/hints/ec2.json').and_return('')
     end
   end