Module: Beaker::Options::HostsFileParser

Defined in:
lib/beaker/options/hosts_file_parser.rb

Overview

A set of functions to parse hosts files

Constant Summary collapse

PERMITTED_YAML_CLASSES = 
[
  'Beaker',
  'Beaker::DSL::TestTagging::PlatformTagConfiner',
  'Beaker::Logger',
  'Beaker::Options::OptionsHash',
  'Beaker::Platform',
  'Beaker::Result',
  'File',
  'IO',
  'Logger',
  'Logger::Formatter',
  'Logger::LogDevice',
  'Monitor',
  'Net::SSH::Prompt',
  'StringifyHash',
  'StringIO',
  'Symbol',
  'Time',
]

Class Method Summary collapse

Class Method Details

.fix_roles_array(host_options) ⇒ Object

Make sure the roles array is present for all hosts



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# File 'lib/beaker/options/hosts_file_parser.rb', line 82

def self.fix_roles_array(host_options)
  host_options['HOSTS'].each_key do |host|
    host_options['HOSTS'][host]['roles'] ||= []
  end
  host_options = host_options.merge(host_options.delete('CONFIG')) if host_options.has_key?('CONFIG')
  host_options
end

.merge_hosts_yaml(host_options, error_message) ⇒ OptionsHash

Merges YAML read in the passed block into given OptionsHash

Parameters:

  • host_options (OptionsHash) —

    Host information hash

  • error_message (String) —

    Message to print if Psych::SyntaxError is raised during block execution

Returns:

  • (OptionsHash) —

    Updated host_options with host info merged



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# File 'lib/beaker/options/hosts_file_parser.rb', line 96

def self.merge_hosts_yaml(host_options, error_message)
  begin
    loaded_host_options = yield
  rescue Psych::SyntaxError => e
    error_message << e.to_s
    raise ArgumentError, error_message
  end

  host_options.merge(loaded_host_options)
end

.new_host_options ⇒ OptionsHash

Convenience method to create new OptionsHashes with a HOSTS section

Returns:



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# File 'lib/beaker/options/hosts_file_parser.rb', line 74

def self.new_host_options
  host_options = Beaker::Options::OptionsHash.new
  host_options['HOSTS'] ||= {}
  host_options
end

.parse_hosts_file(hosts_file_path = nil) ⇒ OptionsHash

Read the contents of the hosts.cfg into an OptionsHash, merge the ‘CONFIG’ section into the OptionsHash, return OptionsHash

Examples:

hosts_hash = HostsFileParser.parse_hosts_file('sample.cfg')
hosts_hash == {:HOSTS=>{:"pe-ubuntu-lucid"=>{:roles=>["agent", "dashboard", "database", "master"], ... }

Parameters:

  • hosts_file_path (String) (defaults to: nil) —

    The path to the hosts file

Returns:

  • (OptionsHash) —

    The contents of the hosts file as an OptionsHash

Raises:

  • (ArgumentError) —

    Raises if hosts_file_path is not a valid YAML file

  • (Errno::ENOENT) —

    File not found error: hosts_file doesn’t exist



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# File 'lib/beaker/options/hosts_file_parser.rb', line 35

def self.parse_hosts_file(hosts_file_path = nil)
  require 'erb'

  host_options = new_host_options
  return host_options unless hosts_file_path

  error_message = "#{hosts_file_path} is not a valid YAML file\n\t"
  host_options = self.merge_hosts_yaml(host_options, error_message) do
    hosts_file_path = File.expand_path(hosts_file_path)

    raise "#{hosts_file_path} is not a valid path" unless File.exist?(hosts_file_path)

    process_yaml(File.read(hosts_file_path), binding)
  end
  fix_roles_array(host_options)
end

.parse_hosts_string(hosts_def_yaml = nil) ⇒ OptionsHash

Read the contents of a host definition as a string into an OptionsHash

Parameters:

  • hosts_def_yaml (String) (defaults to: nil) —

    YAML hosts definition

Returns:

  • (OptionsHash) —

    Contents of the hosts file as an OptionsHash

Raises:

  • (ArgumentError) —

    If hosts_def_yaml is not a valid YAML string



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# File 'lib/beaker/options/hosts_file_parser.rb', line 58

def self.parse_hosts_string(hosts_def_yaml = nil)
  require 'erb'

  host_options = new_host_options
  return host_options unless hosts_def_yaml

  error_message = "#{hosts_def_yaml}\nis not a valid YAML string\n\t"
  host_options = self.merge_hosts_yaml(host_options, error_message) do
    process_yaml(hosts_def_yaml, binding)
  end
  fix_roles_array(host_options)
end

.process_yaml(template, b) ⇒ 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.

A helper to parse the YAML file and apply ERB templating

Parameters:

  • path (String) —

    Path to the file to read

  • b (Binding) —

    The binding to pass to ERB rendering



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# File 'lib/beaker/options/hosts_file_parser.rb', line 112

def self.process_yaml(template, b)
  erb_obj = ERB.new(template, trim_mode: '-')
  YAML.safe_load(erb_obj.result(b), permitted_classes: PERMITTED_YAML_CLASSES, aliases: true)
end