Class: Chef::Resource

Inherits:
Object show all
Extended by:
Mixin::ConvertToClassName
Includes:
Mixin::CheckHelper, Mixin::ConvertToClassName, Mixin::Deprecation, Mixin::Language, Mixin::ParamsValidate
Defined in:
lib/chef/resource.rb,
lib/chef/resource/csh.rb,
lib/chef/resource/env.rb,
lib/chef/resource/git.rb,
lib/chef/resource/log.rb,
lib/chef/resource/scm.rb,
lib/chef/resource/bash.rb,
lib/chef/resource/cron.rb,
lib/chef/resource/file.rb,
lib/chef/resource/link.rb,
lib/chef/resource/ohai.rb,
lib/chef/resource/perl.rb,
lib/chef/resource/ruby.rb,
lib/chef/resource/user.rb,
lib/chef/resource/group.rb,
lib/chef/resource/mdadm.rb,
lib/chef/resource/mount.rb,
lib/chef/resource/route.rb,
lib/chef/resource/deploy.rb,
lib/chef/resource/python.rb,
lib/chef/resource/script.rb,
lib/chef/resource/execute.rb,
lib/chef/resource/package.rb,
lib/chef/resource/service.rb,
lib/chef/resource/chef_gem.rb,
lib/chef/resource/erl_call.rb,
lib/chef/resource/ifconfig.rb,
lib/chef/resource/template.rb,
lib/chef/resource/directory.rb,
lib/chef/resource/breakpoint.rb,
lib/chef/resource/ruby_block.rb,
lib/chef/resource/subversion.rb,
lib/chef/resource/apt_package.rb,
lib/chef/resource/conditional.rb,
lib/chef/resource/gem_package.rb,
lib/chef/resource/ips_package.rb,
lib/chef/resource/remote_file.rb,
lib/chef/resource/rpm_package.rb,
lib/chef/resource/yum_package.rb,
lib/chef/resource/dpkg_package.rb,
lib/chef/resource/http_request.rb,
lib/chef/resource_platform_map.rb,
lib/chef/resource/cookbook_file.rb,
lib/chef/resource/pacman_package.rb,
lib/chef/resource/deploy_revision.rb,
lib/chef/resource/freebsd_package.rb,
lib/chef/resource/portage_package.rb,
lib/chef/resource/smartos_package.rb,
lib/chef/resource/solaris_package.rb,
lib/chef/resource/macports_package.rb,
lib/chef/resource/remote_directory.rb,
lib/chef/resource/timestamped_deploy.rb,
lib/chef/resource/easy_install_package.rb

Defined Under Namespace

Classes: AptPackage, Bash, Breakpoint, ChefGem, Conditional, CookbookFile, Cron, Csh, Deploy, DeployBranch, DeployRevision, Directory, DpkgPackage, EasyInstallPackage, Env, ErlCall, Execute, File, FreebsdPackage, GemPackage, Git, Group, HttpRequest, Ifconfig, IpsPackage, Link, Log, MacportsPackage, Mdadm, Mount, Notification, Ohai, Package, PacmanPackage, Perl, PlatformMap, PortagePackage, Python, RemoteDirectory, RemoteFile, Route, RpmPackage, Ruby, RubyBlock, Scm, Script, Service, SmartOSPackage, SolarisPackage, Subversion, Template, TimestampedDeploy, User, YumPackage

Constant Summary collapse

FORBIDDEN_IVARS =
[:@run_context, :@node, :@not_if, :@only_if, :@enclosing_provider]
HIDDEN_IVARS =
[:@allowed_actions, :@resource_name, :@source_line, :@run_context, :@name, :@node, :@not_if, :@only_if, :@elapsed_time, :@enclosing_provider]

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Mixin::ConvertToClassName

convert_to_class_name, convert_to_snake_case, filename_to_qualified_string, snake_case_basename

Methods included from Mixin::Deprecation

#deprecated_ivar

Methods included from Mixin::Language

#data_bag, #data_bag_item, #platform?, #platform_family?, #search, #value_for_platform, #value_for_platform_family

Methods included from Mixin::ParamsValidate

#set_or_return, #validate

Methods included from Mixin::CheckHelper

#set_if_args

Constructor Details

#initialize(name, run_context = nil) ⇒ Resource

Each notify entry is a resource/action pair, modeled as an Struct with a #resource and #action member


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# File 'lib/chef/resource.rb', line 197

def initialize(name, run_context=nil)
  @name = name
  @run_context = run_context
  @noop = nil
  @before = nil
  @params = Hash.new
  @provider = nil
  @allowed_actions = [ :nothing ]
  @action = :nothing
  @updated = false
  @updated_by_last_action = false
  @supports = {}
  @ignore_failure = false
  @retries = 0
  @retry_delay = 2
  @not_if = []
  @only_if = []
  @source_line = nil
  @elapsed_time = 0

  @node = run_context ? deprecated_ivar(run_context.node, :node, :warn) : nil
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method_symbol, *args, &block) ⇒ Object

If an unknown method is invoked, determine whether the enclosing Provider's lexical scope can fulfill the request. E.g. This happens when the Resource's block invokes new_resource.


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# File 'lib/chef/resource.rb', line 255

def method_missing(method_symbol, *args, &block)
  if enclosing_provider && enclosing_provider.respond_to?(method_symbol)
    enclosing_provider.send(method_symbol, *args, &block)
  else
    raise NoMethodError, "undefined method `#{method_symbol.to_s}' for #{self.class.to_s}"
  end
end

Instance Attribute Details

#allowed_actionsObject

Returns the value of attribute allowed_actions


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# File 'lib/chef/resource.rb', line 177

def allowed_actions
  @allowed_actions
end

#cookbook_nameObject

Returns the value of attribute cookbook_name


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# File 'lib/chef/resource.rb', line 179

def cookbook_name
  @cookbook_name
end

#elapsed_timeObject (readonly)

Returns the value of attribute elapsed_time


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# File 'lib/chef/resource.rb', line 192

def elapsed_time
  @elapsed_time
end

#enclosing_providerObject

Returns the value of attribute enclosing_provider


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# File 'lib/chef/resource.rb', line 181

def enclosing_provider
  @enclosing_provider
end

#not_if_argsObject (readonly)

Returns the value of attribute not_if_args


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# File 'lib/chef/resource.rb', line 189

def not_if_args
  @not_if_args
end

#only_if_argsObject (readonly)

Returns the value of attribute only_if_args


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# File 'lib/chef/resource.rb', line 190

def only_if_args
  @only_if_args
end

#paramsObject

Returns the value of attribute params


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# File 'lib/chef/resource.rb', line 175

def params
  @params
end

#provider(arg = nil) ⇒ Object

Returns the value of attribute provider


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# File 'lib/chef/resource.rb', line 176

def provider
  @provider
end

#recipe_nameObject

Returns the value of attribute recipe_name


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# File 'lib/chef/resource.rb', line 180

def recipe_name
  @recipe_name
end

#resource_nameObject (readonly)

Returns the value of attribute resource_name


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# File 'lib/chef/resource.rb', line 188

def resource_name
  @resource_name
end

#retries(arg = nil) ⇒ Object

Returns the value of attribute retries


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# File 'lib/chef/resource.rb', line 183

def retries
  @retries
end

#retry_delay(arg = nil) ⇒ Object

Returns the value of attribute retry_delay


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# File 'lib/chef/resource.rb', line 184

def retry_delay
  @retry_delay
end

#run_contextObject

Returns the value of attribute run_context


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# File 'lib/chef/resource.rb', line 178

def run_context
  @run_context
end

#source_lineObject

Returns the value of attribute source_line


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# File 'lib/chef/resource.rb', line 182

def source_line
  @source_line
end

#updatedObject

Returns the value of attribute updated


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# File 'lib/chef/resource.rb', line 186

def updated
  @updated
end

Class Method Details

.attribute(attr_name, validation_opts = {}) ⇒ Object


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# File 'lib/chef/resource.rb', line 687

def self.attribute(attr_name, validation_opts={})
  # This atrocity is the only way to support 1.8 and 1.9 at the same time
  # When you're ready to drop 1.8 support, do this:
  # define_method attr_name.to_sym do |arg=nil|
  # etc.
  shim_method=<<-SHIM
  def #{attr_name}(arg=nil)
    _set_or_return_#{attr_name}(arg)
  end
  SHIM
  class_eval(shim_method)

  define_method("_set_or_return_#{attr_name.to_s}".to_sym) do |arg|
    set_or_return(attr_name.to_sym, arg, validation_opts)
  end
end

.build_from_file(cookbook_name, filename, run_context) ⇒ Object


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# File 'lib/chef/resource.rb', line 704

def self.build_from_file(cookbook_name, filename, run_context)
  rname = filename_to_qualified_string(cookbook_name, filename)

  # Add log entry if we override an existing light-weight resource.
  class_name = convert_to_class_name(rname)
  overriding = Chef::Resource.const_defined?(class_name)
  Chef::Log.info("#{class_name} light-weight resource already initialized -- overriding!") if overriding

  new_resource_class = Class.new self do |cls|

    # default initialize method that ensures that when initialize is finally
    # wrapped (see below), super is called in the event that the resource
    # definer does not implement initialize
    def initialize(name, run_context)
      super(name, run_context)
    end

    @actions_to_create = []

    class << cls
      include Chef::Mixin::FromFile

      attr_accessor :run_context
      attr_reader :action_to_set_default

      def node
        self.run_context.node
      end

      def actions_to_create
        @actions_to_create
      end

      define_method(:default_action) do |action_name|
        actions_to_create.push(action_name)
        @action_to_set_default = action_name
      end

      define_method(:actions) do |*action_names|
        actions_to_create.push(*action_names)
      end
    end

    # set the run context in the class instance variable
    cls.run_context = run_context

    # load resource definition from file
    cls.class_from_file(filename)

    # create a new constructor that wraps the old one and adds the actions
    # specified in the DSL
    old_init = instance_method(:initialize)

    define_method(:initialize) do |name, *optional_args|
      args_run_context = optional_args.shift
      @resource_name = rname.to_sym
      old_init.bind(self).call(name, args_run_context)
      @action = self.class.action_to_set_default || @action
      allowed_actions.push(self.class.actions_to_create).flatten!
    end
  end

  # register new class as a Chef::Resource
  class_name = convert_to_class_name(rname)
  Chef::Resource.const_set(class_name, new_resource_class)
  Chef::Log.debug("Loaded contents of #{filename} into a resource named #{rname} defined in Chef::Resource::#{class_name}")

  new_resource_class
end

.dsl_nameObject


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# File 'lib/chef/resource.rb', line 171

def self.dsl_name
  convert_to_snake_case(name, 'Chef::Resource')
end

.identity_attr(attr_name = nil) ⇒ Object

Set or return the “identity attribute” for this resource class. This is generally going to be the “name attribute” for this resource. In other words, the resource type plus this attribute uniquely identify a given bit of state that chef manages. For a File resource, this would be the path, for a package resource, it will be the package name. This will show up in chef-client's audit records as a searchable field.


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# File 'lib/chef/resource.rb', line 159

def self.identity_attr(attr_name=nil)
  @identity_attr ||= nil
  @identity_attr = attr_name if attr_name

  # If this class doesn't have an identity attr, we'll defer to the superclass:
  if @identity_attr || !superclass.respond_to?(:identity_attr)
    @identity_attr
  else
    superclass.identity_attr
  end
end

.json_create(o) ⇒ Object


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# File 'lib/chef/resource.rb', line 672

def self.json_create(o)
  resource = self.new(o["instance_vars"]["@name"])
  o["instance_vars"].each do |k,v|
    resource.instance_variable_set("@#{k}".to_sym, v)
  end
  resource
end

.platform_mapObject


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# File 'lib/chef/resource.rb', line 786

def self.platform_map
  @@platform_map ||= PlatformMap.new
end

.provider_base(arg = nil) ⇒ Object

Resources that want providers namespaced somewhere other than Chef::Provider can set the namespace with provider_base Ex:

class MyResource < Chef::Resource
  provider_base Chef::Provider::Deploy
  # ...other stuff
end

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# File 'lib/chef/resource.rb', line 781

def self.provider_base(arg=nil)
  @provider_base ||= arg
  @provider_base ||= Chef::Provider
end

.provides(short_name, opts = {}) ⇒ Object

Maps a short_name (and optionally a platform and version) to a Chef::Resource. This allows finer grained per platform resource attributes and the end of overloaded resource definitions (I'm looking at you Chef::Resource::Package) Ex:

class WindowsFile < Chef::Resource
  provides :file, :on_platforms => ["windows"]
  # ...other stuff
end

TODO: 2011-11-02 schisamo - platform_version support


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# File 'lib/chef/resource.rb', line 801

def self.provides(short_name, opts={})
  short_name_sym = short_name
  if short_name.kind_of?(String)
    short_name.downcase!
    short_name.gsub!(/\s/, "_")
    short_name_sym = short_name.to_sym
  end
  if opts.has_key?(:on_platforms)
    platforms = [opts[:on_platforms]].flatten
    platforms.each do |p|
      p = :default if :all == p.to_sym
      platform_map.set(
        :platform => p.to_sym,
        :short_name => short_name_sym,
        :resource => self
      )
    end
  else
    platform_map.set(
      :short_name => short_name_sym,
      :resource => self
    )
  end
end

.resource_for_node(short_name, node) ⇒ Object

Returns a resource based on a short_name and a node's platform and version.

Parameters

short_name<Symbol>

short_name of the resource (ie :directory)

node<Chef::Node>

Node object to look up platform and version in

Returns

<Chef::Resource>

returns the proper Chef::Resource class


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# File 'lib/chef/resource.rb', line 849

def self.resource_for_node(short_name, node)
  begin
    platform, version = Chef::Platform.find_platform_and_version(node)
  rescue ArgumentError
  end
  resource = resource_for_platform(short_name, platform, version)
  resource
end

.resource_for_platform(short_name, platform = nil, version = nil) ⇒ Object

Returns a resource based on a short_name anda platform and version.

Parameters

short_name<Symbol>

short_name of the resource (ie :directory)

platform<Symbol,String>

platform name

version<String>

platform version

Returns

<Chef::Resource>

returns the proper Chef::Resource class


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# File 'lib/chef/resource.rb', line 836

def self.resource_for_platform(short_name, platform=nil, version=nil)
  platform_map.get(short_name, platform, version)
end

.state_attrs(*attr_names) ⇒ Object

Set or return the list of “state attributes” implemented by the Resource subclass. State attributes are attributes that describe the desired state of the system, such as file permissions or ownership. In general, state attributes are attributes 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, attributes that are not “state attributes” 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.


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# File 'lib/chef/resource.rb', line 141

def self.state_attrs(*attr_names)
  @state_attrs ||= []
  @state_attrs = attr_names unless attr_names.empty?

  # Return *all* state_attrs that this class has, including inherited ones
  if superclass.respond_to?(:state_attrs)
    superclass.state_attrs + @state_attrs
  else
    @state_attrs
  end
end

Instance Method Details

#action(arg = nil) ⇒ Object


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# File 'lib/chef/resource.rb', line 299

def action(arg=nil)
  if arg
    action_list = arg.kind_of?(Array) ? arg : [ arg ]
    action_list = action_list.collect { |a| a.to_sym }
    action_list.each do |action|
      validate(
        {
          :action => action,
        },
        {
          :action => { :kind_of => Symbol, :equal_to => @allowed_actions },
        }
      )
    end
    @action = action_list
  else
    @action
  end
end

#add_notification(action, resources, timing = :delayed) ⇒ Object


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# File 'lib/chef/resource.rb', line 384

def add_notification(action, resources, timing=:delayed)
  resources = [resources].flatten
  resources.each do |resource|
    case timing.to_s
    when 'delayed'
      notifies_delayed(action, resource)
    when 'immediate', 'immediately'
      notifies_immediately(action, resource)
    else
      raise ArgumentError,  "invalid timing: #{timing} for notifies(#{action}, #{resources.inspect}, #{timing}) resource #{self} "\
                            "Valid timings are: :delayed, :immediate, :immediately"
    end
  end

  true
end

#after_createdObject

Hook to allow a resource to run specific code after creation


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# File 'lib/chef/resource.rb', line 681

def after_created
  nil
end

#as_json(*a) ⇒ Object

as_json does most of the to_json heavy lifted. It exists here in case activesupport is loaded. activesupport will call as_json and skip over to_json. This ensure json is encoded as expected


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# File 'lib/chef/resource.rb', line 481

def as_json(*a)
  safe_ivars = instance_variables.map { |ivar| ivar.to_sym } - FORBIDDEN_IVARS
  instance_vars = Hash.new
  safe_ivars.each do |iv|
    instance_vars[iv.to_s.sub(/^@/, '')] = instance_variable_get(iv)
  end
  results = {
    'json_class' => self.class.name,
    'instance_vars' => instance_vars
  }
end

#cookbook_versionObject


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# File 'lib/chef/resource.rb', line 562

def cookbook_version
  if cookbook_name
    run_context.cookbook_collection[cookbook_name]
  end
end

#customize_exception(e) ⇒ Object


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# File 'lib/chef/resource.rb', line 631

def customize_exception(e)
  new_exception = e.exception("#{self} (#{defined_at}) had an error: #{e.class.name}: #{e.message}")
  new_exception.set_backtrace(e.backtrace)
  new_exception
end

#defined_atObject


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# File 'lib/chef/resource.rb', line 551

def defined_at
  if cookbook_name && recipe_name && source_line
    "#{cookbook_name}::#{recipe_name} line #{source_line.split(':')[1]}"
  elsif source_line
    file, line_no = source_line.split(':')
    "#{file} line #{line_no}"
  else
    "dynamically defined"
  end
end

#delayed_notificationsObject


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# File 'lib/chef/resource.rb', line 421

def delayed_notifications
  run_context.delayed_notifications(self)
end

#epic_fail(arg = nil) ⇒ Object


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# File 'lib/chef/resource.rb', line 357

def epic_fail(arg=nil)
  ignore_failure(arg)
end

#eventsObject


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# File 'lib/chef/resource.rb', line 568

def events
  run_context.events
end

#identityObject

Returns the value of the identity attribute, if declared. Falls back to #name if no identity attribute is declared.


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# File 'lib/chef/resource.rb', line 231

def identity
  if identity_attr = self.class.identity_attr
    send(identity_attr)
  else
    name
  end
end

#ignore_failure(arg = nil) ⇒ Object


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# File 'lib/chef/resource.rb', line 333

def ignore_failure(arg=nil)
  set_or_return(
    :ignore_failure,
    arg,
    :kind_of => [ TrueClass, FalseClass ]
  )
end

#immediate_notificationsObject


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# File 'lib/chef/resource.rb', line 417

def immediate_notifications
  run_context.immediate_notifications(self)
end

#inspectObject


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# File 'lib/chef/resource.rb', line 471

def inspect
  ivars = instance_variables.map { |ivar| ivar.to_sym } - FORBIDDEN_IVARS
  ivars.inject("<#{to_s}") do |str, ivar|
    str << " #{ivar}: #{instance_variable_get(ivar).inspect}"
  end << ">"
end

#is(*args) ⇒ Object


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# File 'lib/chef/resource.rb', line 443

def is(*args)
  if args.size == 1
    args.first
  else
    return *args
  end
end

#load_prior_resourceObject


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# File 'lib/chef/resource.rb', line 263

def load_prior_resource
  begin
    prior_resource = run_context.resource_collection.lookup(self.to_s)
    Chef::Log.debug("Setting #{self.to_s} to the state of the prior #{self.to_s}")
    prior_resource.instance_variables.each do |iv|
      unless iv.to_sym == :@source_line || iv.to_sym == :@action
        self.instance_variable_set(iv, prior_resource.instance_variable_get(iv))
      end
    end
    true
  rescue Chef::Exceptions::ResourceNotFound => e
    true
  end
end

#name(name = nil) ⇒ Object


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# File 'lib/chef/resource.rb', line 319

def name(name=nil)
  set_if_args(@name, name) do
    raise ArgumentError, "name must be a string!" unless name.kind_of?(String)
    @name = name
  end
end

#nodeObject


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# File 'lib/chef/resource.rb', line 248

def node
  run_context && run_context.node
end

#noop(tf = nil) ⇒ Object


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# File 'lib/chef/resource.rb', line 326

def noop(tf=nil)
  set_if_args(@noop, tf) do
    raise ArgumentError, "noop must be true or false!" unless tf == true || tf == false
    @noop = tf
  end
end

#not_if(command = nil, opts = {}, &block) ⇒ Object

If command is a block, returns false if the block returns true, true if it returns false. (“Do not run this resource if the block is true”)

If the command is not a block, executes the command. If it returns a 0 exitstatus, returns false. (“Do not run this resource if the command returns 0”)

Parameters

command<String>

A a string to execute.

opts<Hash>

Options control the execution of the command

block<Proc>

A ruby block to run. Ignored if a command is given.

Evaluation

  • evaluates to true if the block is false, or if the command returns a non-zero exit status.

  • evaluates to false if the block is true, or if the command returns a 0 exit status.


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# File 'lib/chef/resource.rb', line 544

def not_if(command=nil, opts={}, &block)
  if command || block_given?
    @not_if << Conditional.not_if(command, opts, &block)
  end
  @not_if
end

#notifies(*args) ⇒ Object


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# File 'lib/chef/resource.rb', line 361

def notifies(*args)
  unless ( args.size > 0 && args.size < 4)
    raise ArgumentError, "Wrong number of arguments for notifies: should be 1-3 arguments, you gave #{args.inspect}"
  end

  if args.size > 1 # notifies(:action, resource) OR notifies(:action, resource, :immediately)
    add_notification(*args)
  else
    # This syntax is so weird. surely people will just give us one hash?
    notifications = args.flatten
    notifications.each do |resources_notifications|
      resources_notifications.each do |resource, notification|
        action, timing = notification[0], notification[1]
        Chef::Log.debug "Adding notification from resource #{self} to `#{resource.inspect}' => `#{notification.inspect}'"
        add_notification(action, resource, timing)
      end
    end
  end
rescue NoMethodError
  Chef::Log.fatal("Error processing notifies(#{args.inspect}) on #{self}")
  raise
end

#notifies_delayed(action, resource_spec) ⇒ Object


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# File 'lib/chef/resource.rb', line 413

def notifies_delayed(action, resource_spec)
  run_context.notifies_delayed(Notification.new(resource_spec, action, self))
end

#notifies_immediately(action, resource_spec) ⇒ Object


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# File 'lib/chef/resource.rb', line 409

def notifies_immediately(action, resource_spec)
  run_context.notifies_immediately(Notification.new(resource_spec, action, self))
end

#only_if(command = nil, opts = {}, &block) ⇒ Object

If command is a block, returns true if the block returns true, false if it returns false. (“Only run this resource if the block is true”)

If the command is not a block, executes the command. If it returns any status other than 0, it returns false (clearly, a 0 status code is true)

Parameters

command<String>

A a string to execute.

opts<Hash>

Options control the execution of the command

block<Proc>

A ruby block to run. Ignored if a command is given.

Evaluation

  • evaluates to true if the block is true, or if the command returns 0

  • evaluates to false if the block is false, or if the command returns a non-zero exit code.


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# File 'lib/chef/resource.rb', line 523

def only_if(command=nil, opts={}, &block)
  if command || block_given?
    @only_if << Conditional.only_if(command, opts, &block)
  end
  @only_if
end

#provider_for_action(action) ⇒ Object


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# File 'lib/chef/resource.rb', line 618

def provider_for_action(action)
  # leverage new platform => short_name => resource
  # which requires explicitly setting provider in
  # resource class
  if self.provider
    provider = self.provider.new(self, self.run_context)
    provider.action = action
    provider
  else # fall back to old provider resolution
    Chef::Platform.provider_for_resource(self, action)
  end
end

#resolve_notification_referencesObject

Iterates over all immediate and delayed notifications, calling resolve_resource_reference on each in turn, causing them to resolve lazy/forward references.


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# File 'lib/chef/resource.rb', line 404

def resolve_notification_references
  run_context.immediate_notifications(self).each { |n| n.resolve_resource_reference(run_context.resource_collection) }
  run_context.delayed_notifications(self).each {|n| n.resolve_resource_reference(run_context.resource_collection) }
end

#resources(*args) ⇒ Object


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# File 'lib/chef/resource.rb', line 425

def resources(*args)
  run_context.resource_collection.find(*args)
end

#run_action(action, notification_type = nil, notifying_resource = nil) ⇒ Object


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# File 'lib/chef/resource.rb', line 572

def run_action(action, notification_type=nil, notifying_resource=nil)
  # reset state in case of multiple actions on the same resource.
  @elapsed_time = 0
  start_time = Time.now
  events.resource_action_start(self, action, notification_type, notifying_resource)
  # Try to resolve lazy/forward references in notifications again to handle
  # the case where the resource was defined lazily (ie. in a ruby_block)
  resolve_notification_references
  validate_action(action)

  if Chef::Config[:verbose_logging] || Chef::Log.level == :debug
    # This can be noisy
    Chef::Log.info("Processing #{self} action #{action} (#{defined_at})")
  end

  # ensure that we don't leave @updated_by_last_action set to true
  # on accident
  updated_by_last_action(false)

  begin
    return if should_skip?(action)
    provider_for_action(action).run_action
  rescue Exception => e
    if ignore_failure
      Chef::Log.error("#{self} (#{defined_at}) had an error: #{e.message}; ignore_failure is set, continuing")
      events.resource_failed(self, action, e)
    elsif retries > 0
      events.resource_failed_retriable(self, action, retries, e)
      @retries -= 1
      Chef::Log.info("Retrying execution of #{self}, #{retries} attempt(s) left")
      sleep retry_delay
      retry
    else
      events.resource_failed(self, action, e)
      raise customize_exception(e)
    end
  ensure
    @elapsed_time = Time.now - start_time
    events.resource_completed(self)
  end
end

#should_skip?(action) ⇒ Boolean

Evaluates not_if and only_if conditionals. Returns a falsey value if any of the conditionals indicate that this resource should be skipped, i.e., if an only_if evaluates to false or a not_if evaluates to true.

If this resource should be skipped, returns the first conditional that “fails” its check. Subsequent conditionals are not evaluated, so in general it's not a good idea to rely on side effects from not_if or only_if commands/blocks being evaluated.

Returns:

  • (Boolean)

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# File 'lib/chef/resource.rb', line 644

def should_skip?(action)
  conditionals = only_if + not_if
  return false if conditionals.empty?

  conditionals.find do |conditional|
    if conditional.continue?
      false
    else
      events.resource_skipped(self, action, conditional)
      Chef::Log.debug("Skipping #{self} due to #{conditional.description}")
      true
    end
  end
end

#stateObject

Returns a Hash of attribute => value for the state attributes declared in the resource's class definition.


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# File 'lib/chef/resource.rb', line 222

def state
  self.class.state_attrs.inject({}) do |state_attrs, attr_name|
    state_attrs[attr_name] = send(attr_name)
    state_attrs
  end
end

#subscribes(action, resources, timing = :delayed) ⇒ Object


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# File 'lib/chef/resource.rb', line 429

def subscribes(action, resources, timing=:delayed)
  resources = [resources].flatten
  resources.each do |resource|
    if resource.is_a?(String)
      resource = Chef::Resource.new(resource, run_context)
    end
    if resource.run_context.nil?
      resource.run_context = run_context
    end
    resource.add_notification(action, self, timing)
  end
  true
end

#supports(args = {}) ⇒ Object


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# File 'lib/chef/resource.rb', line 278

def supports(args={})
  if args.any?
    @supports = args
  else
    @supports
  end
end

#to_hashObject


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# File 'lib/chef/resource.rb', line 499

def to_hash
  safe_ivars = instance_variables.map { |ivar| ivar.to_sym } - FORBIDDEN_IVARS
  instance_vars = Hash.new
  safe_ivars.each do |iv|
    key = iv.to_s.sub(/^@/,'').to_sym
    instance_vars[key] = instance_variable_get(iv)
  end
  instance_vars
end

#to_json(*a) ⇒ Object

Serialize this object as a hash


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# File 'lib/chef/resource.rb', line 494

def to_json(*a)
  results = as_json
  results.to_json(*a)
end

#to_sObject


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# File 'lib/chef/resource.rb', line 451

def to_s
  "#{@resource_name}[#{@name}]"
end

#to_textObject


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# File 'lib/chef/resource.rb', line 455

def to_text
  ivars = instance_variables.map { |ivar| ivar.to_sym } - HIDDEN_IVARS
  text = "# Declared in #{@source_line}\n\n"
  text << self.class.dsl_name + "(\"#{name}\") do\n"
  ivars.each do |ivar|
    if (value = instance_variable_get(ivar)) && !(value.respond_to?(:empty?) && value.empty?)
      value_string = value.respond_to?(:to_text) ? value.to_text : value.inspect
      text << "  #{ivar.to_s.sub(/^@/,'')} #{value_string}\n"
    end
  end
  [@not_if, @only_if].flatten.each do |conditional|
    text << "  #{conditional.to_text}\n"
  end
  text << "end\n"
end

#updated?Boolean

Returns:

  • (Boolean)

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# File 'lib/chef/resource.rb', line 668

def updated?
  updated
end

#updated_by_last_action(true_or_false) ⇒ Object


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# File 'lib/chef/resource.rb', line 659

def updated_by_last_action(true_or_false)
  @updated ||= true_or_false
  @updated_by_last_action = true_or_false
end

#updated_by_last_action?Boolean

Returns:

  • (Boolean)

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# File 'lib/chef/resource.rb', line 664

def updated_by_last_action?
  @updated_by_last_action
end

#validate_action(action) ⇒ Object

Raises:

  • (ArgumentError)

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# File 'lib/chef/resource.rb', line 614

def validate_action(action)
  raise ArgumentError, "nil is not a valid action for resource #{self}" if action.nil?
end