aboutsummaryrefslogtreecommitdiffstats
path: root/activemodel/lib/active_model/serialization.rb
blob: f659419293ba439c8ef51c031d5f74c820e6bdcd (plain) (blame)
1
2
3
4
5
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
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
require 'active_support/core_ext/hash/except'
require 'active_support/core_ext/hash/slice'

module ActiveModel
  # == Active Model Serialization
  #
  # Provides a basic serialization to a serializable_hash for your object.
  #
  # A minimal implementation could be:
  #
  #   class Person
  #
  #     include ActiveModel::Serialization
  #
  #     attr_accessor :name
  #
  #     def attributes
  #       @attributes ||= {'name' => nil}
  #     end
  #
  #   end
  #
  # Which would provide you with:
  #
  #   person = Person.new
  #   person.serializable_hash   # => {"name"=>nil}
  #   person.name = "Bob"
  #   person.serializable_hash   # => {"name"=>"Bob"}
  #
  # You need to declare some sort of attributes hash which contains the attributes
  # you want to serialize and their current value.
  #
  # Most of the time though, you will want to include the JSON or XML
  # serializations.  Both of these modules automatically include the
  # ActiveModel::Serialization module, so there is no need to explicitly
  # include it.
  #
  # So a minimal implementation including XML and JSON would be:
  #
  #   class Person
  #
  #     include ActiveModel::Serializers::JSON
  #     include ActiveModel::Serializers::Xml
  #
  #     attr_accessor :name
  #
  #     def attributes
  #       @attributes ||= {'name' => nil}
  #     end
  #
  #   end
  #
  # Which would provide you with:
  #
  #   person = Person.new
  #   person.serializable_hash   # => {"name"=>nil}
  #   person.as_json             # => {"name"=>nil}
  #   person.to_json             # => "{\"name\":null}"
  #   person.to_xml              # => "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<serial-person...
  #
  #   person.name = "Bob"
  #   person.serializable_hash   # => {"name"=>"Bob"}
  #   person.as_json             # => {"name"=>"Bob"}
  #   person.to_json             # => "{\"name\":\"Bob\"}"
  #   person.to_xml              # => "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<serial-person...
  #
  # Valid options are <tt>:only</tt>, <tt>:except</tt> and <tt>:methods</tt> .
  module Serialization
    def serializable_hash(options = nil)
      options ||= {}

      only   = Array.wrap(options[:only]).map(&:to_s)
      except = Array.wrap(options[:except]).map(&:to_s)

      attribute_names = attributes.keys.sort
      if only.any?
        attribute_names &= only
      elsif except.any?
        attribute_names -= except
      end

      method_names = Array.wrap(options[:methods]).map { |n| n if respond_to?(n.to_s) }.compact
      Hash[(attribute_names + method_names).map { |n| [n, send(n)] }]
    end
  end
end