Module: Mongoid::Mirrored::RootMethods

Included in:
ClassMethods
Defined in:
lib/mongoid-mirrored/root/root_methods.rb

Instance Method Summary collapse

Instance Method Details

#define_create_mirrors ⇒ Object 



21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
 
# File 'lib/mongoid-mirrored/root/root_methods.rb', line 21

def define_create_mirrors
  unless self.instance_methods.include?(:_create_mirrors)
    self.class_eval <<-EOF
      after_create  :_create_mirrors
    EOF
  end
  define_method :_create_mirrors do
    
    # each embedded class will be touched by the callbacks
    # this should be used with care or write operations could get very slow
    embedding_models[:all].each do |embedding_model|
      # attributes that will be used to define the root and embedding classes and instances
      embedding_string = embedding_model.to_s
      _embedding_klass = self.class.symbol_to_class(embedding_model)
      embedding_instance = eval(embedding_string)

      # Only tries to create mirrored document if the embedding instance is given
      if embedding_instance
        _embedding_klass.collection.update({ :_id => embedding_instance.id }, '$push' => {self.class.root_association => attributes.except("#{embedding_string}_id")})
      end
    end
  end
end

#define_destroy_mirrors ⇒ Object 



81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
 
# File 'lib/mongoid-mirrored/root/root_methods.rb', line 81

def define_destroy_mirrors
  unless self.instance_methods.include?(:_destroy_mirrors)
    self.class_eval <<-EOF
      after_destroy  :_destroy_mirrors
    EOF
  end
  # destroys the mirrored document when the destroy method is called on the root document
  # or when the root document establishes a relationship with another embedding document
  define_method :_destroy_mirrors do |changed_embedding_instance = nil|
    embedding_models[:all].each do |embedding_model|

      # attributes that will be used to define the root and embedding classes and instances
      embedding_string = embedding_model.to_s
      _embedding_klass = self.class.symbol_to_class(embedding_model)
      embedding_instance = eval(embedding_string)
      if embedding_instance
        id_to_destroy = changed_embedding_instance || embedding_instance.id
        _embedding_klass.collection.update({ :_id => id_to_destroy }, '$pull' => {self.class.root_association => { :_id => id}})
      end
    end
  end
end

#define_root_callbacks ⇒ Object

Define callbacks for root class that don’t trigger callbacks on the mirror classes



5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
 
# File 'lib/mongoid-mirrored/root/root_methods.rb', line 5

def define_root_callbacks
  if [:both, :from_root].include?(embedding_options[:sync_direction])
    if embedding_options[:sync_events].include?(:create) || embedding_options[:sync_events] == [:all]
      define_create_mirrors
    end
    
    if embedding_options[:sync_events].include?(:update) || embedding_options[:sync_events] == [:all]
      define_update_mirrors
    end
    
    if embedding_options[:sync_events].include?(:destroy) || embedding_options[:sync_events] == [:all]
      define_destroy_mirrors
    end
  end
end

#define_update_mirrors ⇒ Object 



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
 
# File 'lib/mongoid-mirrored/root/root_methods.rb', line 45

def define_update_mirrors
  unless self.instance_methods.include?(:_update_mirrors)
    self.class_eval <<-EOF
      before_update  :_update_mirrors
    EOF
  end
  # updates the mirrored document when one or more attributes of the parent document is changed
  # if the root document changes the embedding document, the mirrored document is deleted from the previous list
  # and another mirrored document is created for the new embedding document
  define_method :_update_mirrors do
    embedding_models[:all].each do |embedding_model|

      # attributes that will be used to define the root and embedding classes and instances
      embedding_string = embedding_model.to_s
      embedding_instance = eval(embedding_string)
      _embedding_klass = self.class.symbol_to_class(embedding_model)

      if embedding_instance
        if eval("#{embedding_string}_id_changed?")
          _create_mirrors
          _destroy_mirrors(eval("#{embedding_string}_id_was"))
        else
          # using positional modifier $ to find embedded document to be updated
          # traverses the attributes hash to inject positional modifier
          # eg: contents => ;comments.$.contents =>
          nested_attr = {}
          attributes.except("#{embedding_string}_id").each_pair do |k,v|
            nested_attr["#{self.class.root_association}.$.#{k}"] = v
          end
          _embedding_klass.collection.update({"#{self.class.root_association}._id" => id}, '$set' => nested_attr )
        end
      end
    end
  end
end

#write_fields_with_options(&block) ⇒ Object

writes the block passed to the mirrored_in method in the Root Calss defines instance methods used in callbacks triggered by the root documents



106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
 
# File 'lib/mongoid-mirrored/root/root_methods.rb', line 106

def write_fields_with_options(&block)
  index_params = ""
  index_params << ", :index => true" if embedding_options[:index]
  index_params << ", :background => true" if embedding_options[:index] && embedding_options[:background_index]
  
  embedding_models[:all].each do |embedding_model|
    self.class_eval <<-EOT
      belongs_to :#{embedding_model} #{index_params}
    EOT
  end
  # writes shared fields and methods to root document
  yield
  
  define_root_callbacks
  
end