Class: Puppet::Parser::ParserFactory

Inherits:
Object
  • Object
show all
Defined in:
lib/puppet/parser/parser_factory.rb

Overview

The ParserFactory makes selection of parser possible. Currently, it is possible to switch between two different parsers:

  • classic_parser, the parser in 3.1

  • eparser, the Expression Based Parser

Class Method Summary collapse

Class Method Details

.assert_rgen_installed ⇒ Object

Asserts that RGen >= 0.6.6 is installed by checking that certain behavior is available. Note that this assert is expensive as it also requires puppet/pops (if not already loaded).



43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
 
# File 'lib/puppet/parser/parser_factory.rb', line 43

def self.assert_rgen_installed
  @@asserted ||= false
  return if @@asserted
  @@asserted = true
  begin
    require 'rgen/metamodel_builder'
  rescue LoadError
    raise Puppet::DevError.new("The gem 'rgen' version >= 0.7.0 is required when using the setting '--parser future'. Please install 'rgen'.")
  end
  # Since RGen is optional, there is nothing specifying its version.
  # It is not installed in any controlled way, so not possible to use gems to check (it may be installed some other way).
  # Instead check that "eContainer, and eContainingFeature" has been installed.
  require 'puppet/pops'
  begin
    litstring = Puppet::Pops::Model::LiteralString.new();
    container = Puppet::Pops::Model::ArithmeticExpression.new();
    container.left_expr = litstring
    raise "no eContainer" if litstring.eContainer() != container
    raise "no eContainingFeature" if litstring.eContainingFeature() != :left_expr
  rescue => e
    # TODO: RGen can raise exceptions for other reasons!
    raise Puppet::DevError.new("The gem 'rgen' version >= 0.7.0 is required when using '--parser future'. An older version is installed, please update.")
  end
end

.classic_parser(environment) ⇒ Object

Creates an instance of the classic parser.



21
22
23
24
25
 
# File 'lib/puppet/parser/parser_factory.rb', line 21

def self.classic_parser(environment)
  # avoid expensive require if already loaded
  require 'puppet/parser' unless defined? Puppet::Parser::Parser
  Puppet::Parser::Parser.new(environment)
end

.code_merger ⇒ Object 



68
69
70
71
72
73
74
 
# File 'lib/puppet/parser/parser_factory.rb', line 68

def self.code_merger
  if Puppet[:parser] == 'future'
    Puppet::Pops::Parser::CodeMerger.new
  else
    Puppet::Parser::CodeMerger.new
  end
end

.evaluating_parser(file_watcher) ⇒ Object

Creates an instance of an E4ParserAdapter that adapts an EvaluatingParser to the 3x way of parsing.



30
31
32
33
34
35
36
37
38
 
# File 'lib/puppet/parser/parser_factory.rb', line 30

def self.evaluating_parser(file_watcher)
  # Since RGen is optional, test that it is installed
  assert_rgen_installed()
  unless defined?(Puppet::Pops::Parser::E4ParserAdapter)
    require 'puppet/parser/e4_parser_adapter'
    require 'puppet/pops/parser/code_merger'
  end
  E4ParserAdapter.new(file_watcher)
end

.parser(environment) ⇒ Object

Produces a parser instance for the given environment



11
12
13
14
15
16
17
 
# File 'lib/puppet/parser/parser_factory.rb', line 11

def self.parser(environment)
  if Puppet[:parser] == 'future'
    evaluating_parser(environment)
  else
    classic_parser(environment)
  end
end