Class: Facter::Util::Fact

Inherits:
Object
  • Object
show all
Defined in:
lib/facter/util/fact.rb

Overview

This class represents a fact. Each fact has a name and multiple resolutions.

Create facts using Facter.add

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, options = {}) ⇒ Fact

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Creates a new fact, with no resolution mechanisms. See Facter.add for the public API for creating facts.

Parameters:

  • name (String) —

    the fact name

  • options (Hash) (defaults to: {}) —

    optional parameters

Options Hash (options):

  • :ldapname (String) —

    set the ldapname property on the fact



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# File 'lib/facter/util/fact.rb', line 27

def initialize(name, options = {})
  @name = name.to_s.downcase.intern

  extract_ldapname_option!(options)

  @ldapname ||= @name.to_s

  @resolves = []
  @searching = false

  @value = nil
end

Instance Attribute Details

#ldapname ⇒ String

Deprecated.

Returns:

  • (String) 


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# File 'lib/facter/util/fact.rb', line 18

def ldapname
  @ldapname
end

#name ⇒ String

The name of the fact

Returns:

  • (String) 


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# File 'lib/facter/util/fact.rb', line 14

def name
  @name
end

Instance Method Details

#add(options = {}, &block) ⇒ Facter::Util::Resolution

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Adds a new resolution. This requires a block, which will then be evaluated in the context of the new resolution.

Parameters:

  • options (Hash) (defaults to: {}) —

    A hash of options to set on the resolution

Returns:



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# File 'lib/facter/util/fact.rb', line 49

def add(options = {}, &block)
  define_resolution(nil, options, &block)
end

#define_resolution(resolution_name, options = {}, &block) ⇒ Facter::Util::Resolution

Define a new named resolution or return an existing resolution with the given name.

Parameters:

  • resolution_name (String) —

    The name of the resolve to define or look up

  • options (Hash) (defaults to: {}) —

    A hash of options to set on the resolution

Returns:



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# File 'lib/facter/util/fact.rb', line 61

def define_resolution(resolution_name, options = {}, &block)

  resolution_type = options.delete(:type) || :simple

  resolve = create_or_return_resolution(resolution_name, resolution_type)

  resolve.set_options(options) unless options.empty?
  resolve.evaluate(&block) if block

  resolve
rescue => e
  Facter.log_exception(e, "Unable to add resolve #{resolution_name.inspect} for fact #{@name}: #{e.message}")
end

#extract_ldapname_option!(options) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Deprecated. 


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# File 'lib/facter/util/fact.rb', line 124

def extract_ldapname_option!(options)
  if options[:ldapname]
    Facter.warnonce("ldapname is deprecated and will be removed in a future version")
    self.ldapname = options.delete(:ldapname)
  end
end

#flush ⇒ void

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

This method returns an undefined value.

Flushes any cached values.



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# File 'lib/facter/util/fact.rb', line 92

def flush
  @resolves.each { |r| r.flush }
  @value = nil
end

#resolution(name) ⇒ Facter::Util::Resolution?

Retrieve an existing resolution by name

Parameters:

  • name (String)

Returns:



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# File 'lib/facter/util/fact.rb', line 81

def resolution(name)
  return nil if name.nil?

  @resolves.find { |resolve| resolve.name == name }
end

#value ⇒ Object

Returns the value for this fact. This searches all resolutions by suitability and weight (see Resolution). If no suitable resolution is found, it returns nil.



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# File 'lib/facter/util/fact.rb', line 102

def value
  return @value if @value

  if @resolves.empty?
    Facter.debug "No resolves for %s" % @name
    return nil
  end

  searching do

    suitable_resolutions = sort_by_weight(find_suitable_resolutions(@resolves))
    @value = find_first_real_value(suitable_resolutions)

    announce_when_no_suitable_resolution(suitable_resolutions)
    announce_when_no_value_found(@value)

    @value
  end
end