Class: ActiveRecord::Associations::JoinDependency

Inherits:
Object
  • Object
show all
Extended by:
ActiveSupport::Autoload
Defined in:
lib/active_record/associations/join_dependency.rb,
lib/active_record/associations/join_dependency/join_base.rb,
lib/active_record/associations/join_dependency/join_part.rb,
lib/active_record/associations/join_dependency/join_association.rb

Overview

:nodoc:

Defined Under Namespace

Classes: Aliases, JoinAssociation, JoinBase, JoinPart

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(base, table, associations, join_type) ⇒ JoinDependency

Returns a new instance of JoinDependency.



71
72
73
74
75
 
# File 'lib/active_record/associations/join_dependency.rb', line 71

def initialize(base, table, associations, join_type)
  tree = self.class.make_tree associations
  @join_root = JoinBase.new(base, table, build(tree, base))
  @join_type = join_type
end

Class Method Details

.make_tree(associations) ⇒ Object 



47
48
49
50
51
 
# File 'lib/active_record/associations/join_dependency.rb', line 47

def self.make_tree(associations)
  hash = {}
  walk_tree associations, hash
  hash
end

.walk_tree(associations, hash) ⇒ Object 



53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
 
# File 'lib/active_record/associations/join_dependency.rb', line 53

def self.walk_tree(associations, hash)
  case associations
  when Symbol, String
    hash[associations.to_sym] ||= {}
  when Array
    associations.each do |assoc|
      walk_tree assoc, hash
    end
  when Hash
    associations.each do |k, v|
      cache = hash[k] ||= {}
      walk_tree v, cache if v
    end
  else
    raise ConfigurationError, associations.inspect
  end
end

Instance Method Details

#apply_column_aliases(relation) ⇒ Object 



153
154
155
156
 
# File 'lib/active_record/associations/join_dependency.rb', line 153

def apply_column_aliases(relation)
  @join_root_alias = relation.select_values.empty?
  relation._select!(-> { aliases.columns })
end

#base_klass ⇒ Object 



77
78
79
 
# File 'lib/active_record/associations/join_dependency.rb', line 77

def base_klass
  join_root.base_klass
end

#each(&block) ⇒ Object 



158
159
160
 
# File 'lib/active_record/associations/join_dependency.rb', line 158

def each(&block)
  join_root.each(&block)
end

#instantiate(result_set, strict_loading_value, &block) ⇒ Object 



105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
 
# File 'lib/active_record/associations/join_dependency.rb', line 105

def instantiate(result_set, strict_loading_value, &block)
  primary_key = aliases.column_alias(join_root, join_root.primary_key)

  seen = Hash.new { |i, parent|
    i[parent] = Hash.new { |j, child_class|
      j[child_class] = {}
    }
  }.compare_by_identity

  model_cache = Hash.new { |h, klass| h[klass] = {} }
  parents = model_cache[join_root]

  column_aliases = aliases.column_aliases(join_root)
  column_names = []

  result_set.columns.each do |name|
    column_names << name unless /\At\d+_r\d+\z/.match?(name)
  end

  if column_names.empty?
    column_types = {}
  else
    column_types = result_set.column_types
    unless column_types.empty?
      attribute_types = join_root.attribute_types
      column_types = column_types.slice(*column_names).delete_if { |k, _| attribute_types.key?(k) }
    end
    column_aliases += column_names.map! { |name| Aliases::Column.new(name, name) }
  end

  message_bus = ActiveSupport::Notifications.instrumenter

  payload = {
    record_count: result_set.length,
    class_name: join_root.base_klass.name
  }

  message_bus.instrument("instantiation.active_record", payload) do
    result_set.each { |row_hash|
      parent_key = primary_key ? row_hash[primary_key] : row_hash
      parent = parents[parent_key] ||= join_root.instantiate(row_hash, column_aliases, column_types, &block)
      construct(parent, join_root, row_hash, seen, model_cache, strict_loading_value)
    }
  end

  parents.values
end

#join_constraints(joins_to_add, alias_tracker, references) ⇒ Object 



85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
 
# File 'lib/active_record/associations/join_dependency.rb', line 85

def join_constraints(joins_to_add, alias_tracker, references)
  @alias_tracker = alias_tracker
  @joined_tables = {}
  @references = {}

  references.each do |table_name|
    @references[table_name.to_sym] = table_name if table_name.is_a?(Arel::Nodes::SqlLiteral)
  end unless references.empty?

  joins = make_join_constraints(join_root, join_type)

  joins.concat joins_to_add.flat_map { |oj|
    if join_root.match? oj.join_root
      walk(join_root, oj.join_root, oj.join_type)
    else
      make_join_constraints(oj.join_root, oj.join_type)
    end
  }
end

#reflections ⇒ Object 



81
82
83
 
# File 'lib/active_record/associations/join_dependency.rb', line 81

def reflections
  join_root.drop(1).map!(&:reflection)
end