Module: Mongoid::Changeable

Extended by:
ActiveSupport::Concern
Included in:
Composable
Defined in:
lib/mongoid/changeable.rb

Overview

Defines behavior for dirty tracking.

Defined Under Namespace

Modules: ClassMethods

Instance Method Summary collapse

Instance Method Details

#attribute_before_last_save(attr) ⇒ Object

Returns the original value of an attribute before the last save.

This method is useful in after callbacks to get the original value of

an attribute before the save that triggered the callbacks to run.

Parameters:

  • attr (Symbol | String) —

    The name of the attribute.

Returns:

  • (Object) —

    Value of the attribute before the last save.



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# File 'lib/mongoid/changeable.rb', line 146

def attribute_before_last_save(attr)
  attr = database_field_name(attr)
  attributes_before_last_save[attr]
end

#changed ⇒ Array<String>

Get the changed attributes for the document.

Examples:

Get the changed attributes.

model.changed

Returns:

  • (Array<String>) —

    The changed attributes.



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# File 'lib/mongoid/changeable.rb', line 15

def changed
  changed_attributes.keys.select { |attr| attribute_change(attr) }
end

#changed? ⇒ true | false

Has the document changed?

Examples:

Has the document changed?

model.changed?

Returns:

  • (true | false) —

    If the document is changed.



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# File 'lib/mongoid/changeable.rb', line 25

def changed?
  changes.values.any? { |val| val } || children_changed?
end

#changed_attributes ⇒ Hash<String, Object>

Get the attribute changes.

Examples:

Get the attribute changes.

model.changed_attributes

Returns:

  • (Hash<String, Object>) —

    The attribute changes.



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# File 'lib/mongoid/changeable.rb', line 44

def changed_attributes
  @changed_attributes ||= {}
end

#changes ⇒ Hash<String, Array<Object, Object> ] The changes.

Get all the changes for the document.

Examples:

Get all the changes.

model.changes

Returns:

  • (Hash<String, Array<Object, Object> ] The changes.) —

    Hash<String, Array<Object, Object> ] The changes.



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# File 'lib/mongoid/changeable.rb', line 54

def changes
  _changes = {}
  changed.each do |attr|
    change = attribute_change(attr)
    _changes[attr] = change if change
  end
  _changes.with_indifferent_access
end

#children_changed? ⇒ true | false

Note:

This intentionally only considers children and not descendants.

Have any children (embedded documents) of this document changed?

Returns:

  • (true | false) —

    If any children have changed.



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# File 'lib/mongoid/changeable.rb', line 34

def children_changed?
  _children.any?(&:changed?)
end

#move_changes ⇒ Object

Call this method after save, so the changes can be properly switched.

This will unset the memoized children array, set new record flag to false, set the document as validated, and move the dirty changes.

Examples:

Move the changes to previous.

person.move_changes


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# File 'lib/mongoid/changeable.rb', line 70

def move_changes
  @changes_before_last_save = @previous_changes
  @previous_changes = changes
  @attributes_before_last_save = @previous_attributes
  @previous_attributes = attributes.dup
  Atomic::UPDATES.each do |update|
    send(update).clear
  end
  changed_attributes.clear
end

#post_persist ⇒ Object

Things that need to execute after a document has been persisted.

Examples:

Handle post persistence.

document.post_persist


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# File 'lib/mongoid/changeable.rb', line 85

def post_persist
  reset_persisted_descendants
  reset_attributes_before_type_cast
  move_changes
end

#previous_changes ⇒ Hash<String, Array<Object, Object> ] The previous changes.

Get the previous changes on the document.

Examples:

Get the previous changes.

model.previous_changes

Returns:

  • (Hash<String, Array<Object, Object> ] The previous changes.) —

    Hash<String, Array<Object, Object> ] The previous changes.



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# File 'lib/mongoid/changeable.rb', line 97

def previous_changes
  @previous_changes ||= {}
end

#remove_change(name) ⇒ Object

Remove a change from the dirty attributes hash. Used by the single field atomic updaters.

Examples:

Remove a flagged change.

model.remove_change(:field)

Parameters:

  • name (Symbol | String) —

    The name of the field.



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# File 'lib/mongoid/changeable.rb', line 108

def remove_change(name)
  changed_attributes.delete(name.to_s)
end

#saved_change_to_attribute(attr) ⇒ Array<Object> | nil

Returns the change to an attribute during the last save.

Parameters:

  • attr (Symbol | String) —

    The name of the attribute.

Returns:

  • (Array<Object> | nil) —

    If the attribute was changed, returns an array containing the original value and the saved value, otherwise nil.



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# File 'lib/mongoid/changeable.rb', line 157

def saved_change_to_attribute(attr)
  attr = database_field_name(attr)
  previous_changes[attr]
end

#saved_change_to_attribute?(attr, **kwargs) ⇒ true | false

Returns whether this attribute changed during the last save.

This method is useful in after callbacks, to see the change

in an attribute during the save that triggered the callbacks to run.

Parameters:

  • attr (String) —

    The name of the attribute.

  • **kwargs —

    The optional keyword arguments.

Returns:

  • (true | false) —

    Whether the attribute has changed during the last save.



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# File 'lib/mongoid/changeable.rb', line 174

def saved_change_to_attribute?(attr, **kwargs)
  changes = saved_change_to_attribute(attr)
  return false unless changes.is_a?(Array)
  if kwargs.key?(:from) && kwargs.key?(:to)
    changes.first == kwargs[:from] && changes.last == kwargs[:to]
  elsif kwargs.key?(:from)
    changes.first == kwargs[:from]
  elsif kwargs.key?(:to)
    changes.last == kwargs[:to]
  else
    true
  end
end

#setters ⇒ Hash

Gets all the new values for each of the changed fields, to be passed to a MongoDB $set modifier.

Examples:

Get the setters for the atomic updates.

person = Person.new(:title => "Sir")
person.title = "Madam"
person.setters # returns { "title" => "Madam" }

Returns:

  • (Hash) —

    A Hash of atomic setters.



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# File 'lib/mongoid/changeable.rb', line 121

def setters
  mods = {}
  changes.each_pair do |name, changes|
    if changes
      old, new = changes
      field = fields[name]
      key = atomic_attribute_name(name)
      if field && field.resizable?
        field.add_atomic_changes(self, name, key, mods, new, old)
      else
        mods[key] = new unless atomic_unsets.include?(key)
      end
    end
  end
  mods
end

#will_save_change_to_attribute?(attr, **kwargs) ⇒ true | false

Returns whether this attribute change the next time we save.

This method is useful in validations and before callbacks to determine

if the next call to save will change a particular attribute.

Parameters:

  • attr (String) —

    The name of the attribute.

  • **kwargs —

    The optional keyword arguments.

Returns:

  • (true | false) —

    Whether the attribute change the next time we save.



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# File 'lib/mongoid/changeable.rb', line 200

def will_save_change_to_attribute?(attr, **kwargs)
  attribute_changed?(attr, **kwargs)
end