Module: ActiveRecord::Core

Extended by:
ActiveSupport::Concern
Includes:
ActiveModel::Access
Included in:
Base
Defined in:
lib/active_record/core.rb

Overview

Active Record Core

Defined Under Namespace

Modules: ClassMethods

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#strict_loading_modeObject (readonly)

Returns the value of attribute strict_loading_mode.



648
649
650
# File 'lib/active_record/core.rb', line 648

def strict_loading_mode
  @strict_loading_mode
end

Instance Method Details

#<=>(other_object) ⇒ Object

Allows sort on objects



587
588
589
590
591
592
593
# File 'lib/active_record/core.rb', line 587

def <=>(other_object)
  if other_object.is_a?(self.class)
    to_key <=> other_object.to_key
  else
    super
  end
end

#==(comparison_object) ⇒ Object Also known as: eql?

Returns true if comparison_object is the same exact object, or comparison_object is of the same type and self has an ID and it is equal to comparison_object.id.

Note that new records are different from any other record by definition, unless the other record is the receiver itself. Besides, if you fetch existing records with select and leave the ID out, you’re on your own, this predicate will return false.

Note also that destroying a record preserves its ID in the model instance, so deleted models are still comparable.



553
554
555
556
557
558
# File 'lib/active_record/core.rb', line 553

def ==(comparison_object)
  super ||
    comparison_object.instance_of?(self.class) &&
    primary_key_values_present? &&
    comparison_object.id == id
end

#blank?Boolean

:nodoc:

Returns:

  • (Boolean)


599
600
601
# File 'lib/active_record/core.rb', line 599

def blank? # :nodoc:
  false
end

#connection_handlerObject



660
661
662
# File 'lib/active_record/core.rb', line 660

def connection_handler
  self.class.connection_handler
end

#encode_with(coder) ⇒ Object

Populate coder with attributes about this record that should be serialized. The structure of coder defined in this method is guaranteed to match the structure of coder passed to the #init_with method.

Example:

class Post < ActiveRecord::Base
end
coder = {}
Post.new.encode_with(coder)
coder # => {"attributes" => {"id" => nil, ... }}


538
539
540
541
542
# File 'lib/active_record/core.rb', line 538

def encode_with(coder)
  self.class.yaml_encoder.encode(@attributes, coder)
  coder["new_record"] = new_record?
  coder["active_record_yaml_version"] = 2
end

#freezeObject

Clone and freeze the attributes hash such that associations are still accessible, even on destroyed records, but cloned models will not be frozen.



576
577
578
579
# File 'lib/active_record/core.rb', line 576

def freeze
  @attributes = @attributes.clone.freeze
  self
end

#frozen?Boolean

Returns true if the attributes hash has been frozen.

Returns:

  • (Boolean)


582
583
584
# File 'lib/active_record/core.rb', line 582

def frozen?
  @attributes.frozen?
end

#hashObject

Delegates to id in order to allow two records of the same type and id to work with something like:

[ Person.find(1), Person.find(2), Person.find(3) ] & [ Person.find(1), Person.find(4) ] # => [ Person.find(1) ]


563
564
565
566
567
568
569
570
571
# File 'lib/active_record/core.rb', line 563

def hash
  id = self.id

  if primary_key_values_present?
    self.class.hash ^ id.hash
  else
    super
  end
end

#init_with(coder, &block) ⇒ Object

Initialize an empty model object from coder. coder should be the result of previously encoding an Active Record model, using #encode_with.

class Post < ActiveRecord::Base
end

old_post = Post.new(title: "hello world")
coder = {}
old_post.encode_with(coder)

post = Post.allocate
post.init_with(coder)
post.title # => 'hello world'


456
457
458
459
460
# File 'lib/active_record/core.rb', line 456

def init_with(coder, &block)
  coder = LegacyYamlAdapter.convert(coder)
  attributes = self.class.yaml_encoder.decode(coder)
  init_with_attributes(attributes, coder["new_record"], &block)
end

#init_with_attributes(attributes, new_record = false) {|_self| ... } ⇒ Object

Initialize an empty model object from attributes. attributes should be an attributes object, and unlike the ‘initialize` method, no assignment calls are made per attribute.

Yields:

  • (_self)

Yield Parameters:



466
467
468
469
470
471
472
473
474
475
476
477
478
# File 'lib/active_record/core.rb', line 466

def init_with_attributes(attributes, new_record = false) # :nodoc:
  @new_record = new_record
  @attributes = attributes

  init_internals

  yield self if block_given?

  _run_find_callbacks
  _run_initialize_callbacks

  self
end

#initialize(attributes = nil) {|_self| ... } ⇒ Object

New objects can be instantiated as either empty (pass no construction parameter) or pre-set with attributes but not yet saved (pass a hash with key names matching the associated table column names). In both instances, valid attribute keys are determined by the column names of the associated table – hence you can’t have attributes that aren’t part of the table columns.

Example

# Instantiates a single new object
User.new(first_name: 'Jamie')

Yields:

  • (_self)

Yield Parameters:



429
430
431
432
433
434
435
436
437
438
439
440
# File 'lib/active_record/core.rb', line 429

def initialize(attributes = nil)
  @new_record = true
  @attributes = self.class._default_attributes.deep_dup

  init_internals
  initialize_internals_callback

  assign_attributes(attributes) if attributes

  yield self if block_given?
  _run_initialize_callbacks
end

#initialize_dup(other) ⇒ Object

:nodoc:



508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
# File 'lib/active_record/core.rb', line 508

def initialize_dup(other) # :nodoc:
  @attributes = @attributes.deep_dup
  if self.class.composite_primary_key?
    @primary_key.each { |key| @attributes.reset(key) }
  else
    @attributes.reset(@primary_key)
  end

  _run_initialize_callbacks

  @new_record               = true
  @previously_new_record    = false
  @destroyed                = false
  @_start_transaction_state = nil

  super
end

#inspectObject

Returns the contents of the record as a nicely formatted string.



665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
# File 'lib/active_record/core.rb', line 665

def inspect
  # We check defined?(@attributes) not to issue warnings if the object is
  # allocated but not initialized.
  inspection = if defined?(@attributes) && @attributes
    attribute_names.filter_map do |name|
      if _has_attribute?(name)
        "#{name}: #{attribute_for_inspect(name)}"
      end
    end.join(", ")
  else
    "not initialized"
  end

  "#<#{self.class} #{inspection}>"
end

#present?Boolean

:nodoc:

Returns:

  • (Boolean)


595
596
597
# File 'lib/active_record/core.rb', line 595

def present? # :nodoc:
  true
end

#pretty_print(pp) ⇒ Object

Takes a PP and prettily prints this record to it, allowing you to get a nice result from pp record when pp is required.



683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
# File 'lib/active_record/core.rb', line 683

def pretty_print(pp)
  return super if custom_inspect_method_defined?
  pp.object_address_group(self) do
    if defined?(@attributes) && @attributes
      attr_names = self.class.attribute_names.select { |name| _has_attribute?(name) }
      pp.seplist(attr_names, proc { pp.text "," }) do |attr_name|
        pp.breakable " "
        pp.group(1) do
          pp.text attr_name
          pp.text ":"
          pp.breakable
          value = _read_attribute(attr_name)
          value = inspection_filter.filter_param(attr_name, value) unless value.nil?
          pp.pp value
        end
      end
    else
      pp.breakable " "
      pp.text "not initialized"
    end
  end
end

#readonly!Object

Marks this record as read only.



656
657
658
# File 'lib/active_record/core.rb', line 656

def readonly!
  @readonly = true
end

#readonly?Boolean

Returns true if the record is read only.

Returns:

  • (Boolean)


604
605
606
# File 'lib/active_record/core.rb', line 604

def readonly?
  @readonly
end

#strict_loading!(value = true, mode: :all) ⇒ Object

Sets the record to strict_loading mode. This will raise an error if the record tries to lazily load an association.

user = User.first
user.strict_loading! # => true
user.comments
=> ActiveRecord::StrictLoadingViolationError

Parameters

  • value - Boolean specifying whether to enable or disable strict loading.

  • :mode - Symbol specifying strict loading mode. Defaults to :all. Using :n_plus_one_only mode will only raise an error if an association that will lead to an n plus one query is lazily loaded.

Examples

user = User.first
user.strict_loading!(false) # => false
user.comments
=> #<ActiveRecord::Associations::CollectionProxy>

user.strict_loading!(mode: :n_plus_one_only)
user.address.city # => "Tatooine"
user.comments
=> ActiveRecord::StrictLoadingViolationError


639
640
641
642
643
644
645
646
# File 'lib/active_record/core.rb', line 639

def strict_loading!(value = true, mode: :all)
  unless [:all, :n_plus_one_only].include?(mode)
    raise ArgumentError, "The :mode option must be one of [:all, :n_plus_one_only] but #{mode.inspect} was provided."
  end

  @strict_loading_mode = mode
  @strict_loading = value
end

#strict_loading?Boolean

Returns true if the record is in strict_loading mode.

Returns:

  • (Boolean)


609
610
611
# File 'lib/active_record/core.rb', line 609

def strict_loading?
  @strict_loading
end

#strict_loading_n_plus_one_only?Boolean

Returns true if the record uses strict_loading with :n_plus_one_only mode enabled.

Returns:

  • (Boolean)


651
652
653
# File 'lib/active_record/core.rb', line 651

def strict_loading_n_plus_one_only?
  @strict_loading_mode == :n_plus_one_only
end