Module: Chef::Mixin::Properties::ClassMethods

Defined in:
lib/chef/mixin/properties.rb

Instance Method Summary collapse

Instance Method Details

#identity_properties(*names) ⇒ Array<Property>

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.

Parameters:

  • names (Array<Symbol>)

    A list of property names to set as the identity.

Returns:

  • (Array<Property>)

    All identity properties.



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# File 'lib/chef/mixin/properties.rb', line 236

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

#included(other) ⇒ Object



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# File 'lib/chef/mixin/properties.rb', line 265

def included(other)
  other.extend ClassMethods
end

#lazy(&block) ⇒ Chef::DelayedEvaluator

Create a lazy value for assignment to a default value.

Parameters:

  • block

    The block to run when the value is retrieved.

Returns:



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# File 'lib/chef/mixin/properties.rb', line 154

def lazy(&block)
  DelayedEvaluator.new(&block)
end

#properties(include_superclass = true) ⇒ Hash<Symbol,Property>

The list of properties defined on this resource.

Everything defined with ‘property` is in this list.

Parameters:

  • include_superclass (Boolean) (defaults to: true)

    ‘true` to include properties defined on superclasses; `false` or `nil` to return the list of properties directly on this class.

Returns:



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# File 'lib/chef/mixin/properties.rb', line 20

def properties(include_superclass = true)
  if include_superclass
    result = {}
    ancestors.reverse_each { |c| result.merge!(c.properties(false)) if c.respond_to?(:properties) }
    result
  else
    @properties ||= {}
  end
end

#property(name, type = NOT_PASSED, **options) ⇒ Object

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.

Examples:

Bare property

property :x

With just a type

property :x, String

With just options

property :x, default: 'hi'

With type and options

property :x, String, default: 'hi'

Parameters:

  • name (Symbol)

    The name of the property.

  • type (Object, Array<Object>) (defaults to: NOT_PASSED)

    The type(s) of this property. If present, this is prepended to the ‘is` validation option.

  • 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`.
    


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# File 'lib/chef/mixin/properties.rb', line 95

def property(name, type = NOT_PASSED, **options)
  name = name.to_sym

  options = options.inject({}) { |memo, (key, value)| memo[key.to_sym] = value; memo }

  options[:instance_variable_name] = :"@#{name}" if !options.has_key?(:instance_variable_name)
  options[:name] = name
  options[: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

#property_type(**options) ⇒ Object

Create a reusable property type that can be used in multiple properties in different resources.

Examples:

property_type(default: 'hi')

Parameters:

  • options (Hash<Symbol,Object>)

    Validation options. see #property for the list of options.



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# File 'lib/chef/mixin/properties.rb', line 143

def property_type(**options)
  Property.derive(**options)
end

#state_properties(*names) ⇒ Array<Property>

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 “`

Parameters:

  • names (Array<Symbol>)

    A list of property names to set as desired state.

Returns:

  • (Array<Property>)

    All properties in desired state.



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# File 'lib/chef/mixin/properties.rb', line 187

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