class Facter::Util::Resolution
This represents a fact resolution. A resolution is a concrete implementation of a fact. A single fact can have many resolutions and the correct resolution will be chosen at runtime. Each time {Facter.add} is called, a new resolution is created and added to the set of resolutions for the fact named in the call. Each resolution has a {#has_weight weight}, which defines its priority over other resolutions, and a set of {#confine confinements}, which defines the conditions under which it will be chosen. All confinements must be satisfied for a fact to be considered suitable.
@api public
Attributes
@api private
@!attribute [r] fact @return [Facter::Util::Fact] @api private
@!attribute [rw] name The name of this resolution. The resolution name should be unique with respect to the given fact. @return [String] @api public
Public Class Methods
Create a new resolution mechanism.
@param name [String] The name of the resolution. @return [void]
@api private
# File lib/facter/util/resolution.rb, line 56 def initialize(name, fact) @name = name @fact = fact @confines = [] @value = nil @timeout = 0 @weight = nil end
Public Instance Methods
Evaluate the given block in the context of this resolution. If a block has already been evaluated emit a warning to that effect.
@return [void]
# File lib/facter/util/resolution.rb, line 73 def evaluate(&block) if @last_evaluated msg = "Already evaluated #{@name}" msg << " at #{@last_evaluated}" if msg.is_a? String msg << ", reevaluating anyways" Facter.warn msg end instance_eval(&block) # Ruby 1.9+ provides the source location of procs which can provide useful # debugging information if a resolution is being evaluated twice. Since 1.8 # doesn't support this we opportunistically provide this information. if block.respond_to? :source_location @last_evaluated = block.source_location.join(':') else @last_evaluated = true end end
# File lib/facter/util/resolution.rb, line 65 def resolution_type :simple end
# File lib/facter/util/resolution.rb, line 93 def set_options(options) if options[:name] @name = options.delete(:name) end if options.has_key?(:value) @value = options.delete(:value) end if options.has_key?(:timeout) @timeout = options.delete(:timeout) end if options.has_key?(:weight) @weight = options.delete(:weight) end if not options.keys.empty? raise ArgumentError, "Invalid resolution options #{options.keys.inspect}" end end
Sets the code block or external program that will be evaluated to get the value of the fact.
@return [void]
@overload setcode(string)
Sets an external program to call to get the value of the resolution @param [String] string the external program to run to get the value
@overload setcode(&block)
Sets the resolution's value by evaluating a block at runtime @param [Proc] block The block to determine the resolution's value. This block is run when the fact is evaluated. Errors raised from inside the block are rescued and printed to stderr.
@api public
# File lib/facter/util/resolution.rb, line 132 def setcode(string = nil, &block) if string @code = Proc.new do output = Facter::Core::Execution.execute(string, :on_fail => nil) if output.nil? or output.empty? nil else output end end elsif block_given? @code = block else raise ArgumentError, "You must pass either code or a block" end end