add partial deep merge cache

3 files changed, 65 insertions, 12 deletions

diff --git a/lib/chef/node.rb b/lib/chef/node.rb
index dbb7852586..6055f0e1e9 100644
--- a/lib/chef/node.rb
+++ b/lib/chef/node.rb
@@ -127,6 +127,7 @@ class Chef
     # Set a normal attribute of this node, but auto-vivify any Mashes that
     # might be missing
     def normal
+      attributes.top_level_breadcrumb = nil
       attributes.set_unless_value_present = false
       attributes.normal
     end
@@ -136,14 +137,17 @@ class Chef
     # Set a normal attribute of this node, auto-vivifying any mashes that are
     # missing, but if the final value already exists, don't set it
     def normal_unless
+      attributes.top_level_breadcrumb = nil
       attributes.set_unless_value_present = true
       attributes.normal
     end
+
     alias_method :set_unless, :normal_unless
 
     # Set a default of this node, but auto-vivify any Mashes that might
     # be missing
     def default
+      attributes.top_level_breadcrumb = nil
       attributes.set_unless_value_present = false
       attributes.default
     end
@@ -151,6 +155,7 @@ class Chef
     # Set a default attribute of this node, auto-vivifying any mashes that are
     # missing, but if the final value already exists, don't set it
     def default_unless
+      attributes.top_level_breadcrumb = nil
       attributes.set_unless_value_present = true
       attributes.default
     end
@@ -158,6 +163,7 @@ class Chef
     # Set an override attribute of this node, but auto-vivify any Mashes that
     # might be missing
     def override
+      attributes.top_level_breadcrumb = nil
       attributes.set_unless_value_present = false
       attributes.override
     end
@@ -165,35 +171,30 @@ class Chef
     # Set an override attribute of this node, auto-vivifying any mashes that
     # are missing, but if the final value already exists, don't set it
     def override_unless
+      attributes.top_level_breadcrumb = nil
       attributes.set_unless_value_present = true
       attributes.override
     end
 
-    def override_attrs
-     attributes.override
-    end
+    alias :override_attrs :override
+    alias :default_attrs :default
+    alias :normal_attrs :normal
 
     def override_attrs=(new_values)
       attributes.override = new_values
     end
 
-    def default_attrs
-      attributes.default
-    end
-
     def default_attrs=(new_values)
       attributes.default = new_values
     end
 
-    def normal_attrs
-      attributes.normal
-    end
-
     def normal_attrs=(new_values)
       attributes.normal = new_values
     end
 
     def automatic_attrs
+      attributes.top_level_breadcrumb = nil
+      attributes.set_unless_value_present = false
       attributes.automatic
     end
 
diff --git a/lib/chef/node/attribute.rb b/lib/chef/node/attribute.rb
index 6130925aea..c780650aac 100644
--- a/lib/chef/node/attribute.rb
+++ b/lib/chef/node/attribute.rb
@@ -175,6 +175,13 @@ class Chef
        # return the automatic level attribute component
        attr_reader :automatic
 
+       # this is used to track the top level key as we descend through method chaining into
+       # a precedence level (e.g. node.default['foo']['bar']['baz']= results in 'foo' here)
+       attr_accessor :top_level_breadcrumb
+
+       # cache of deep merged values by top-level key
+       attr_accessor :deep_merge_cache
+
        def initialize(normal, default, override, automatic)
          @set_unless_present = false
 
@@ -195,6 +202,8 @@ class Chef
          @merged_attributes = nil
          @combined_override = nil
          @combined_default = nil
+         @top_level_breadcrumb = nil
+         @deep_merge_cache = {}
        end
 
        # Debug what's going on with an attribute. +args+ is a path spec to the
@@ -230,51 +239,71 @@ class Chef
          @set_unless_present = setting
        end
 
+       def reset_cache(path = nil)
+         if path.nil?
+           @deep_merge_cache = {}
+         else
+           deep_merge_cache.delete(path)
+         end
+       end
+
+       alias :reset :reset_cache
+
        # Set the cookbook level default attribute component to +new_data+.
        def default=(new_data)
+         reset
          @default = VividMash.new(self, new_data)
        end
 
        # Set the role level default attribute component to +new_data+
        def role_default=(new_data)
+         reset
          @role_default = VividMash.new(self, new_data)
        end
 
        # Set the environment level default attribute component to +new_data+
        def env_default=(new_data)
+         reset
          @env_default = VividMash.new(self, new_data)
        end
 
        # Set the force_default (+default!+) level attributes to +new_data+
        def force_default=(new_data)
+         reset
          @force_default = VividMash.new(self, new_data)
        end
 
        # Set the normal level attribute component to +new_data+
        def normal=(new_data)
+         reset
          @normal = VividMash.new(self, new_data)
        end
 
        # Set the cookbook level override attribute component to +new_data+
        def override=(new_data)
+         reset
          @override = VividMash.new(self, new_data)
        end
 
        # Set the role level override attribute component to +new_data+
        def role_override=(new_data)
+         reset
          @role_override = VividMash.new(self, new_data)
        end
 
        # Set the environment level override attribute component to +new_data+
        def env_override=(new_data)
+         reset
          @env_override = VividMash.new(self, new_data)
        end
 
        def force_override=(new_data)
+         reset
          @force_override = VividMash.new(self, new_data)
        end
 
        def automatic=(new_data)
+         reset
          @automatic = VividMash.new(self, new_data)
        end
 
@@ -284,6 +313,7 @@ class Chef
 
        # clears attributes from all precedence levels
        def rm(*args)
+         reset(args[0])
          # just easier to compute our retval, rather than collect+merge sub-retvals
          ret = args.inject(merged_attributes) do |attr, arg|
            if attr.nil? || !attr.respond_to?(:[])
@@ -314,6 +344,7 @@ class Chef
        #
        # equivalent to: force_default!['foo']['bar'].delete('baz')
        def rm_default(*args)
+         reset(args[0])
          remove_from_precedence_level(force_default!(autovivify: false), *args)
        end
 
@@ -321,6 +352,7 @@ class Chef
        #
        # equivalent to: normal!['foo']['bar'].delete('baz')
        def rm_normal(*args)
+         reset(args[0])
          remove_from_precedence_level(normal!(autovivify: false), *args)
        end
 
@@ -328,6 +360,7 @@ class Chef
        #
        # equivalent to: force_override!['foo']['bar'].delete('baz')
        def rm_override(*args)
+         reset(args[0])
          remove_from_precedence_level(force_override!(autovivify: false), *args)
        end
 
@@ -337,26 +370,36 @@ class Chef
 
        # sets default attributes without merging
        def default!(opts={})
+         # FIXME: do not flush whole cache
+         reset
          MultiMash.new(self, @default, [], opts)
        end
 
        # sets normal attributes without merging
        def normal!(opts={})
+         # FIXME: do not flush whole cache
+         reset
          MultiMash.new(self, @normal, [], opts)
        end
 
        # sets override attributes without merging
        def override!(opts={})
+         # FIXME: do not flush whole cache
+         reset
          MultiMash.new(self, @override, [], opts)
        end
 
        # clears from all default precedence levels and then sets force_default
        def force_default!(opts={})
+         # FIXME: do not flush whole cache
+         reset
          MultiMash.new(self, @force_default, [@default, @env_default, @role_default], opts)
        end
 
        # clears from all override precedence levels and then sets force_override
        def force_override!(opts={})
+         # FIXME: do not flush whole cache
+         reset
          MultiMash.new(self, @force_override, [@override, @env_override, @role_override], opts)
        end
 
@@ -377,7 +420,11 @@ class Chef
        end
 
        def [](key)
-         merged_attributes(key)
+         if deep_merge_cache.has_key?(key)
+           deep_merge_cache[key]
+         else
+           deep_merge_cache[key] = merged_attributes(key)
+         end
        end
 
        def []=(key, value)
diff --git a/lib/chef/node/attribute_collections.rb b/lib/chef/node/attribute_collections.rb
index 3b19a14d1c..333f4864c6 100644
--- a/lib/chef/node/attribute_collections.rb
+++ b/lib/chef/node/attribute_collections.rb
@@ -63,6 +63,7 @@ class Chef
       MUTATOR_METHODS.each do |mutator|
         class_eval(<<-METHOD_DEFN, __FILE__, __LINE__)
           def #{mutator}(*args, &block)
+            root.reset_cache(root.top_level_breadcrumb)
             super
           end
         METHOD_DEFN
@@ -127,6 +128,7 @@ class Chef
       MUTATOR_METHODS.each do |mutator|
         class_eval(<<-METHOD_DEFN, __FILE__, __LINE__)
           def #{mutator}(*args, &block)
+            root.reset_cache(root.top_level_breadcrumb)
             super
           end
         METHOD_DEFN
@@ -138,6 +140,7 @@ class Chef
       end
 
       def [](key)
+        root.top_level_breadcrumb ||= key
         value = super
         if !key?(key)
           value = self.class.new(root)
@@ -148,9 +151,11 @@ class Chef
       end
 
       def []=(key, value)
+        root.top_level_breadcrumb ||= key
         if set_unless? && key?(key)
           self[key]
         else
+          root.reset_cache(root.top_level_breadcrumb)
           super
         end
       end