Adding the ability for parameters to declare that they require a given feature, and resources will not instantiate that parameter if required features are missing. This is mostly useful for properties.

git-svn-id: https://reductivelabs.com/svn/puppet/trunk@2413 980ebf18-57e1-0310-9a29-db15c13687c0

3 files changed, 40 insertions, 1 deletions

diff --git a/lib/puppet/metatype/attributes.rb b/lib/puppet/metatype/attributes.rb
index b4cc5f687..88cff22f5 100644
--- a/lib/puppet/metatype/attributes.rb
+++ b/lib/puppet/metatype/attributes.rb
@@ -201,6 +201,11 @@ class Puppet::Type
             :attributes => options[:attributes],
             &block
         )
+
+        # Grr.
+        if options[:required_features]
+            s.required_features = options[:required_features]
+        end
         
         handle_param_options(name, options)
 
@@ -243,6 +248,11 @@ class Puppet::Type
         
         handle_param_options(name, options)
 
+        # Grr.
+        if options[:required_features]
+            s.required_features = options[:required_features]
+        end
+
         # These might be enabled later.
 #        define_method(name) do
 #            @parameters[name].value
@@ -319,6 +329,11 @@ class Puppet::Type
             s.event = options[:event]
         end
 
+        # Grr.
+        if options[:required_features]
+            s.required_features = options[:required_features]
+        end
+
 #        define_method(name) do
 #            @parameters[name].should
 #        end
@@ -577,6 +592,14 @@ class Puppet::Type
                 [name, self.ref]
         end
 
+        if provider and features = klass.required_features
+            unless provider.class.satisfies?(features)
+                missing = features.find_all { |f| ! provider.class.feature?(f) }
+                info "Provider %s does not support features %s; not managing attribute %s" % [provider.class.name, missing.join(", "), name]
+                return nil
+            end
+        end
+
         # Add parent information at creation time, so it's available
         # during validation.
         options[:parent] = self
diff --git a/lib/puppet/parameter.rb b/lib/puppet/parameter.rb
index 91949e5e3..7c622dbc2 100644
--- a/lib/puppet/parameter.rb
+++ b/lib/puppet/parameter.rb
@@ -3,7 +3,7 @@ require 'puppet/util/methodhelper'
 class Puppet::Parameter < Puppet::Element
     include Puppet::Util::MethodHelper
     class << self
-        attr_reader :validater, :munger, :name, :default
+        attr_reader :validater, :munger, :name, :default, :required_features
         attr_accessor :metaparam, :element
 
         # Define the default value for a given parameter or parameter.  This
@@ -206,6 +206,10 @@ class Puppet::Parameter < Puppet::Element
             return @parameterregexes.dup
         end
 
+        def required_features=(*args)
+            @required_features = args.flatten.collect { |a| a.to_s.downcase.intern }
+        end
+
         # Return the list of valid values.
         def values
             #[@aliasvalues.keys, @parametervalues.keys].flatten
diff --git a/lib/puppet/util/provider_features.rb b/lib/puppet/util/provider_features.rb
index 3aeb627a3..060026bb9 100644
--- a/lib/puppet/util/provider_features.rb
+++ b/lib/puppet/util/provider_features.rb
@@ -127,6 +127,18 @@ module Puppet::Util::ProviderFeatures
                 }
             end
 
+            # Create a method that will list all functional features.
+            @feature_module.send(:define_method, :satisfies?) do |*needed|
+                ret = true
+                needed.flatten.each do |feature|
+                    unless feature?(feature)
+                        ret = false
+                        break
+                    end
+                end
+                ret
+            end
+
             # Create a boolean method for each feature so you can test them
             # individually as you might need.
             @features.each do |name, feature|