Move properties into a mixin module (verbatim move)

1 files changed, 303 insertions, 0 deletions

diff --git a/lib/chef/mixin/properties.rb b/lib/chef/mixin/properties.rb
new file mode 100644
index 0000000000..28ac693472
--- /dev/null
+++ b/lib/chef/mixin/properties.rb
@@ -0,0 +1,303 @@
+require 'chef/delayed_evaluator'
+require 'chef/mixin/params_validate'
+require 'chef/property'
+
+class Chef
+  module Mixin
+    module Properties
+      module ClassMethods
+        #
+        # The list of properties defined on this resource.
+        #
+        # Everything defined with `property` is in this list.
+        #
+        # @param include_superclass [Boolean] `true` to include properties defined
+        #   on superclasses; `false` or `nil` to return the list of properties
+        #   directly on this class.
+        #
+        # @return [Hash<Symbol,Property>] The list of property names and types.
+        #
+        def properties(include_superclass=true)
+          @properties ||= {}
+          if include_superclass
+            if superclass.respond_to?(:properties)
+              superclass.properties.merge(@properties)
+            else
+              @properties.dup
+            end
+          else
+            @properties
+          end
+        end
+
+        #
+        # Create a property on this resource class.
+        #
+        # If a superclass has this property, or if this property has already been
+        # defined by this resource, this will *override* the previous value.
+        #
+        # @param name [Symbol] The name of the property.
+        # @param type [Object,Array<Object>] The type(s) of this property.
+        #   If present, this is prepended to the `is` validation option.
+        # @param options [Hash<Symbol,Object>] Validation options.
+        #   @option options [Object,Array] :is An object, or list of
+        #     objects, that must match the value using Ruby's `===` operator
+        #     (`options[:is].any? { |v| v === value }`).
+        #   @option options [Object,Array] :equal_to An object, or list
+        #     of objects, that must be equal to the value using Ruby's `==`
+        #     operator (`options[:is].any? { |v| v == value }`)
+        #   @option options [Regexp,Array<Regexp>] :regex An object, or
+        #     list of objects, that must match the value with `regex.match(value)`.
+        #   @option options [Class,Array<Class>] :kind_of A class, or
+        #     list of classes, that the value must be an instance of.
+        #   @option options [Hash<String,Proc>] :callbacks A hash of
+        #     messages -> procs, all of which match the value. The proc must
+        #     return a truthy or falsey value (true means it matches).
+        #   @option options [Symbol,Array<Symbol>] :respond_to A method
+        #     name, or list of method names, the value must respond to.
+        #   @option options [Symbol,Array<Symbol>] :cannot_be A property,
+        #     or a list of properties, that the value cannot have (such as `:nil` or
+        #     `:empty`). The method with a questionmark at the end is called on the
+        #     value (e.g. `value.empty?`). If the value does not have this method,
+        #     it is considered valid (i.e. if you don't respond to `empty?` we
+        #     assume you are not empty).
+        #   @option options [Proc] :coerce A proc which will be called to
+        #     transform the user input to canonical form. The value is passed in,
+        #     and the transformed value returned as output. Lazy values will *not*
+        #     be passed to this method until after they are evaluated. Called in the
+        #     context of the resource (meaning you can access other properties).
+        #   @option options [Boolean] :required `true` if this property
+        #     must be present; `false` otherwise. This is checked after the resource
+        #     is fully initialized.
+        #   @option options [Boolean] :name_property `true` if this
+        #     property defaults to the same value as `name`. Equivalent to
+        #     `default: lazy { name }`, except that #property_is_set? will
+        #     return `true` if the property is set *or* if `name` is set.
+        #   @option options [Boolean] :name_attribute Same as `name_property`.
+        #   @option options [Object] :default The value this property
+        #     will return if the user does not set one. If this is `lazy`, it will
+        #     be run in the context of the instance (and able to access other
+        #     properties).
+        #   @option options [Boolean] :desired_state `true` if this property is
+        #     part of desired state. Defaults to `true`.
+        #   @option options [Boolean] :identity `true` if this property
+        #     is part of object identity. Defaults to `false`.
+        #
+        # @example Bare property
+        #   property :x
+        #
+        # @example With just a type
+        #   property :x, String
+        #
+        # @example With just options
+        #   property :x, default: 'hi'
+        #
+        # @example With type and options
+        #   property :x, String, default: 'hi'
+        #
+        def property(name, type=NOT_PASSED, **options)
+          name = name.to_sym
+
+          options.each { |k,v| options[k.to_sym] = v if k.is_a?(String) }
+
+          options[:instance_variable_name] = :"@#{name}" if !options.has_key?(:instance_variable_name)
+          options.merge!(name: name, declared_in: self)
+
+          if type == NOT_PASSED
+            # If a type is not passed, the property derives from the
+            # superclass property (if any)
+            if properties.has_key?(name)
+              property = properties[name].derive(**options)
+            else
+              property = property_type(**options)
+            end
+
+          # If a Property is specified, derive a new one from that.
+          elsif type.is_a?(Property) || (type.is_a?(Class) && type <= Property)
+            property = type.derive(**options)
+
+          # If a primitive type was passed, combine it with "is"
+          else
+            if options[:is]
+              options[:is] = ([ type ] + [ options[:is] ]).flatten(1)
+            else
+              options[:is] = type
+            end
+            property = property_type(**options)
+          end
+
+          local_properties = properties(false)
+          local_properties[name] = property
+
+          property.emit_dsl
+        end
+
+        #
+        # Create a reusable property type that can be used in multiple properties
+        # in different resources.
+        #
+        # @param options [Hash<Symbol,Object>] Validation options. see #property for
+        #   the list of options.
+        #
+        # @example
+        #   property_type(default: 'hi')
+        #
+        def property_type(**options)
+          Property.derive(**options)
+        end
+
+        #
+        # Create a lazy value for assignment to a default value.
+        #
+        # @param block The block to run when the value is retrieved.
+        #
+        # @return [Chef::DelayedEvaluator] The lazy value
+        #
+        def lazy(&block)
+          DelayedEvaluator.new(&block)
+        end
+
+        #
+        # Get or set the list of desired state properties for this resource.
+        #
+        # State properties are properties that describe the desired state
+        # of the system, such as file permissions or ownership.
+        # In general, state properties are properties that could be populated by
+        # examining the state of the system (e.g., File.stat can tell you the
+        # permissions on an existing file). Contrarily, properties that are not
+        # "state properties" usually modify the way Chef itself behaves, for example
+        # by providing additional options for a package manager to use when
+        # installing a package.
+        #
+        # This list is used by the Chef client auditing system to extract
+        # information from resources to describe changes made to the system.
+        #
+        # This method is unnecessary when declaring properties with `property`;
+        # properties are added to state_properties by default, and can be turned off
+        # with `desired_state: false`.
+        #
+        # ```ruby
+        # property :x # part of desired state
+        # property :y, desired_state: false # not part of desired state
+        # ```
+        #
+        # @param names [Array<Symbol>] A list of property names to set as desired
+        #   state.
+        #
+        # @return [Array<Property>] All properties in desired state.
+        #
+        def state_properties(*names)
+          if !names.empty?
+            names = names.map { |name| name.to_sym }.uniq
+
+            local_properties = properties(false)
+            # Add new properties to the list.
+            names.each do |name|
+              property = properties[name]
+              if !property
+                self.property name, instance_variable_name: false, desired_state: true
+              elsif !property.desired_state?
+                self.property name, desired_state: true
+              end
+            end
+
+            # If state_attrs *excludes* something which is currently desired state,
+            # mark it as desired_state: false.
+            local_properties.each do |name,property|
+              if property.desired_state? && !names.include?(name)
+                self.property name, desired_state: false
+              end
+            end
+          end
+
+          properties.values.select { |property| property.desired_state? }
+        end
+
+        #
+        # Set the identity of this resource to a particular set of properties.
+        #
+        # This drives #identity, which returns data that uniquely refers to a given
+        # resource on the given node (in such a way that it can be correlated
+        # across Chef runs).
+        #
+        # This method is unnecessary when declaring properties with `property`;
+        # properties can be added to identity during declaration with
+        # `identity: true`.
+        #
+        # ```ruby
+        # property :x, identity: true # part of identity
+        # property :y # not part of identity
+        # ```
+        #
+        # If no properties are marked as identity, "name" is considered the identity.
+        #
+        # @param names [Array<Symbol>] A list of property names to set as the identity.
+        #
+        # @return [Array<Property>] All identity properties.
+        #
+        def identity_properties(*names)
+          if !names.empty?
+            names = names.map { |name| name.to_sym }
+
+            # Add or change properties that are not part of the identity.
+            names.each do |name|
+              property = properties[name]
+              if !property
+                self.property name, instance_variable_name: false, identity: true
+              elsif !property.identity?
+                self.property name, identity: true
+              end
+            end
+
+            # If identity_properties *excludes* something which is currently part of
+            # the identity, mark it as identity: false.
+            properties.each do |name,property|
+              if property.identity? && !names.include?(name)
+
+                self.property name, identity: false
+              end
+            end
+          end
+
+          result = properties.values.select { |property| property.identity? }
+          result = [ properties[:name] ] if result.empty?
+          result
+        end
+
+        def included(other)
+          other.extend ClassMethods
+        end
+      end
+
+      extend ClassMethods
+
+      include Chef::Mixin::ParamsValidate
+
+      #
+      # Whether this property has been set (or whether it has a default that has
+      # been retrieved).
+      #
+      # @param name [Symbol] The name of the property.
+      # @return [Boolean] `true` if the property has been set.
+      #
+      def property_is_set?(name)
+        property = self.class.properties[name.to_sym]
+        raise ArgumentError, "Property #{name} is not defined in class #{self}" if !property
+        property.is_set?(self)
+      end
+
+      #
+      # Clear this property as if it had never been set. It will thereafter return
+      # the default.
+      # been retrieved).
+      #
+      # @param name [Symbol] The name of the property.
+      #
+      def reset_property(name)
+        property = self.class.properties[name.to_sym]
+        raise ArgumentError, "Property #{name} is not defined in class #{self}" if !property
+        property.reset(self)
+      end
+    end
+  end
+end