Class: ActiveRecord::Associations::Builder::HasAndBelongsToMany

Inherits:
Object
  • Object
show all
Defined in:
lib/active_record/associations/builder/has_and_belongs_to_many.rb

Overview

:nodoc:

Defined Under Namespace

Classes: JoinTableResolver

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(association_name, lhs_model, options) ⇒ HasAndBelongsToMany

Returns a new instance of HasAndBelongsToMany.



38
39
40
41
42
# File 'lib/active_record/associations/builder/has_and_belongs_to_many.rb', line 38

def initialize(association_name, lhs_model, options)
  @association_name = association_name
  @lhs_model = lhs_model
  @options = options
end

Instance Attribute Details

#association_nameObject (readonly)

Returns the value of attribute association_name.



36
37
38
# File 'lib/active_record/associations/builder/has_and_belongs_to_many.rb', line 36

def association_name
  @association_name
end

#lhs_modelObject (readonly)

Returns the value of attribute lhs_model.



36
37
38
# File 'lib/active_record/associations/builder/has_and_belongs_to_many.rb', line 36

def lhs_model
  @lhs_model
end

#optionsObject (readonly)

Returns the value of attribute options.



36
37
38
# File 'lib/active_record/associations/builder/has_and_belongs_to_many.rb', line 36

def options
  @options
end

Instance Method Details

#middle_reflection(join_model) ⇒ Object



95
96
97
98
99
100
101
102
103
104
# File 'lib/active_record/associations/builder/has_and_belongs_to_many.rb', line 95

def middle_reflection(join_model)
  middle_name = [lhs_model.name.downcase.pluralize,
                 association_name].join("_".freeze).gsub("::".freeze, "_".freeze).to_sym
  middle_options = middle_options join_model

  HasMany.create_reflection(lhs_model,
                            middle_name,
                            nil,
                            middle_options)
end

#through_modelObject



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
87
88
89
90
91
92
93
# File 'lib/active_record/associations/builder/has_and_belongs_to_many.rb', line 44

def through_model
  habtm = JoinTableResolver.build lhs_model, association_name, options

  join_model = Class.new(ActiveRecord::Base) {
    class << self;
      attr_accessor :left_model
      attr_accessor :name
      attr_accessor :table_name_resolver
      attr_accessor :left_reflection
      attr_accessor :right_reflection
    end

    def self.table_name
      table_name_resolver.join_table
    end

    def self.compute_type(class_name)
      left_model.compute_type class_name
    end

    def self.add_left_association(name, options)
      belongs_to name, required: false, **options
      self.left_reflection = _reflect_on_association(name)
    end

    def self.add_right_association(name, options)
      rhs_name = name.to_s.singularize.to_sym
      belongs_to rhs_name, required: false, **options
      self.right_reflection = _reflect_on_association(rhs_name)
    end

    def self.retrieve_connection
      left_model.retrieve_connection
    end

    private

      def self.suppress_composite_primary_key(pk)
        pk unless pk.is_a?(Array)
      end
  }

  join_model.name                = "HABTM_#{association_name.to_s.camelize}"
  join_model.table_name_resolver = habtm
  join_model.left_model          = lhs_model

  join_model.add_left_association :left_side, anonymous_class: lhs_model
  join_model.add_right_association association_name, belongs_to_options(options)
  join_model
end