Class: Yacl::Loader::YamlDir

Inherits:
Yacl::Loader show all
Defined in:
lib/yacl/loader/yaml_dir.rb

Overview

YamlDir uses a directory of yaml files to load a Properties instance. It does so as if the entire directory were one big yaml file.

Examples:

Given the following directory structure -

./config
├── database.yml
├── httpserver.yml
└── pipeline.yml

And Creating a YamlDir instance -

yd    = YamlDir.new( :path => "./config" )

Then you will have propertes like these.

props = yd.properties

props.dataabase.adapter # => postgre
props.httpserver.port   # => 80

You may also create a YamlDir and have it use the propety from a Properites instance to indicate the directory to load from.

other_props.config.dir   # => ./config

yd = YamlDir.new( :properties => other_props, :parameter => 'config.dir' )

props = yd.properties
props.dataabase.adapter # => postgre
props.httpserver.port   # => 80

This latter approach use what is used when incorparting a commandline option of a configuration directory within a Plan and the loading of the configuration directory after the pipeline is parsed.

class MyPlan < ::Yacl::Define::Plan
  try MyApp::Cli::Parser
  try Yacl::Loader::YamlDir, :parameter => 'config.dir'
end

Since this use of YamlDir is part of a Plan, the Plan will pass in the Properties accumulated so far to YamlDir

Defined Under Namespace

Classes: Error

Instance Attribute Summary

Attributes inherited from Yacl::Loader

#options

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Yacl::Loader

extract_path, mapify_key, #reference_properties

Constructor Details

#initialize(opt = {}) ⇒ YamlDir

Public: Create a new instance of YamlDir

opts - A Hash of options

:path       - The filesystem path to the directory to load
:properties - A Properties instance to use in conjunction with
              :parameter
:pararmeter - The parameter to look up within the Properties that
              passed in with :properites in order to populate
              :path
:scope      - Scope the loded Properties by this value and only
              return that subset from #properties



64
65
66
67
68
69
70
71
72
73
74
75
76
 
# File 'lib/yacl/loader/yaml_dir.rb', line 64

def initialize( opt = {} )
  super
  @path      = YamlDir.extract_path( options )
  @parameter = YamlDir.mapify_key( options[:parameter] )

  if (not @path) and (reference_properties and @parameter) then
    value = reference_properties.get( *@parameter )
    @path = Pathname.new( value ) if value
  end

  @scope     = options[:scope]
  YamlDir.validate_directory( @path )
end

Class Method Details

.load_properties(dirname, scope) ⇒ Object

Interal: Load the proprerties scoped by the given scope

dirname - The directory from which to load properties scope - Apply the given scope to the loaded properties

Returns a Properties instance.



122
123
124
125
126
127
128
129
130
131
132
133
134
 
# File 'lib/yacl/loader/yaml_dir.rb', line 122

def load_properties( dirname, scope )
  p = Yacl::Properties.new
  Dir.glob( File.join( dirname, '*.yml') ).each do |config_fname|
    file_properties = Yacl::Loader::YamlFile.new( :path => config_fname ).properties
    namespace       = File.basename( config_fname, ".yml" )
    file_properties.each do |k,v|
      args = [ namespace, k ].flatten
      args << v
      p.set( *args )
    end
  end
  return p
end

.validate_and_load_properties(dirname, scope = nil) ⇒ Object

Internal: Validate the directory and then load the properties.

dirname - The directory from which to load properties scope - Apply the given scope to the loaded properties

Returns a Properties instance.



94
95
96
97
 
# File 'lib/yacl/loader/yaml_dir.rb', line 94

def validate_and_load_properties( dirname , scope = nil )
  validate_directory( dirname )
  YamlDir.load_properties( dirname, scope )
end

.validate_directory(path) ⇒ Object

Internal: Validate the given directory.

path - the Pathname to check.

1) make sure it is not nil 2) make sure that it exists 3) make sure that it is a directory

Raise an error if any of the above fail

Returns nothing.

Raises:



110
111
112
113
114
 
# File 'lib/yacl/loader/yaml_dir.rb', line 110

def validate_directory( path )
  raise Error, "No directory specified" unless path
  raise Error, "#{path} does not exist" unless path.exist?
  raise Error, "#{path} is not a directory" unless path.directory?
end

Instance Method Details

#properties ⇒ Object

Public: Return the Properites that are described by the this YamlDir instance

Returns a Properties instance



82
83
84
 
# File 'lib/yacl/loader/yaml_dir.rb', line 82

def properties
  YamlDir.validate_and_load_properties( @path, @scope )
end