How to load yaml with ruby 2.1

Question

I have a the following data in tmp.yml. My goal is to load the data to mysql database.

I have the following code to load the data from tmp.yml:

$LOAD_PATH.unshift( File.join( File.dirname(__FILE__), 'lib' ) )

require 'yaml'
require 'AacflmDirection' # Just an empty class
SITE_PATH = '/var/www/test/testme/asian_cinema/tmp.yml'

doc = YAML::load( File.open( SITE_PATH ) )
puts doc[0]['attributes']['position'] # Expect position = 1

And I got this error. It seems I cannot access it via hash.

load.rb:8:in `<main>': undefined method `[]' for #<AacflmDirection:0x000000023c9fe0> (NoMethodError)


tmp.yml
--- !ruby/object:AacflmDirection
attributes:
  position: "1"
  film_id: "1"
  created_on: 2012-02-06 09:31:31
  page_id: "2671"
  director_id: "1"
  id: "1"
  site_id: "173"
director:
film:
page:
site:
--- !ruby/object:AacflmDirector
assets:
attributes:
  slug: paul-cox
  name: Paul Cox
  bio_markup: ""
  created_on: 2012-02-06 09:31:39
  page_id: "2671"
  id: "51"
  bio:
  site_id: "173"
directions:
draft:
films:
page:
pathprints:
settings_objects:
site: 

Answer 1

You're unserializing objects, not hashes. doc[0] is an instance of AacflmDirection . You need to access them with whatever accessors they provide.

Try doc[0].position .

Answer 2

First, three hyphens --- separate multiple documents in yaml. Then the !ruby/object... followed will deserialize your file to an object, not hash.

In your original code, you only get the AacflmDirection object as your doc variable. Use YAML::load_stream to load all the objects in your yaml.

require 'AacflmDirector'
require 'AacflmDirection'

doc = YAML::load_stream( File.open( SITE_PATH ) )

By that you'll get:

=> [#<AacflmDirection:0x007fa62c1c3a48
 @attributes=
 {"position"=>"1",
  "film_id"=>"1",
  "created_on"=>2012-02-06 17:31:31 +0800
  "page_id"=>"2671",
  "director_id"=>"1",
  "id"=>"1",
  "site_id"=>"173"},
  @director=nil,
  @film=nil,
  @page=nil,
  @site=nil>,
 #<AacflmDirector:0x007fa62c1bbe10
  @assets=nil,
  @attributes=
   {"slug"=>"paul-cox",
    "name"=>"Paul Cox",
    "bio_markup"=>"",
    "created_on"=>2012-02-06 17:31:39 +0800,
    "page_id"=>"2671",
    "id"=>"51",
    "bio"=>nil,
    "site_id"=>"173"},
  @directions=nil,
  @draft=nil,
  @films=nil,
  @page=nil,
  @pathprints=nil,
  @settings_objects=nil,
  @site=nil>]

Then add attr_accessor :attributes in your AacflmDirection class defination. So you can get the value by:

doc[0].attributes["position"]

Answer 3

使用YAML::load_file(SITE_PATH)读取文件并将其转换为Ruby对象。