Puppet Function: is_domain_name

Defined in:
puppet/modules/stdlib/lib/puppet/parser/functions/is_domain_name.rb
Function type:
Ruby 3.x API

Overview

is_domain_name() ⇒ Any

Returns true if the string passed to this function is a syntactically correct domain name.

Returns:

  • (Any) 


6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
 
# File 'puppet/modules/stdlib/lib/puppet/parser/functions/is_domain_name.rb', line 6

newfunction(:is_domain_name, :type => :rvalue, :doc => <<-EOS
Returns true if the string passed to this function is a syntactically correct domain name.
  EOS
) do |arguments|

  if (arguments.size != 1) then
    raise(Puppet::ParseError, "is_domain_name(): Wrong number of arguments "+
      "given #{arguments.size} for 1")
  end

  # Only allow string types
  return false unless arguments[0].is_a?(String)

  domain = arguments[0].dup

  # Limits (rfc1035, 3.1)
  domain_max_length=255
  label_min_length=1
  label_max_length=63

  # Allow ".", it is the top level domain
  return true if domain == '.'

  # Remove the final dot, if present.
  domain.chomp!('.')

  # Check the whole domain
  return false if domain.empty?
  return false if domain.length > domain_max_length

  # The top level domain must be alphabetic if there are multiple labels.
  # See rfc1123, 2.1
  return false if domain.include? '.' and not /\.[A-Za-z]+$/.match(domain)

  # Check each label in the domain
  labels = domain.split('.')
  vlabels = labels.each do |label|
    break if label.length < label_min_length
    break if label.length > label_max_length
    break if label[-1..-1] == '-'
    break if label[0..0] == '-'
    break unless /^[a-z\d-]+$/i.match(label)
  end
  return vlabels == labels

end