module Mongoid::Changeable
Defines behavior for dirty tracking.
Constants
- ATTRIBUTE_UNCHANGED
a singleton object to represent an optional ‘to` or `from` value that was not explicitly provided to
attribute_changed?
Public Instance Methods
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.
@param [ Symbol | String ] attr The name of the attribute.
@return [ Object
] Value of the attribute before the last save.
# File lib/mongoid/changeable.rb, line 141 def attribute_before_last_save(attr) attr = database_field_name(attr) attributes_before_last_save[attr] end
Get the changed attributes for the document.
@example Get the changed attributes.
model.changed
@return [ Array<String> ] The changed attributes.
# File lib/mongoid/changeable.rb, line 14 def changed changed_attributes.keys.select { |attr| attribute_change(attr) } end
Has the document changed?
@example Has the document changed?
model.changed?
@return [ true | false ] If the document is changed.
# File lib/mongoid/changeable.rb, line 24 def changed? changes.values.any? { |val| val } || children_changed? end
Get the attribute changes.
@example Get the attribute changes.
model.changed_attributes
@return [ Hash<String, Object> ] The attribute changes.
# File lib/mongoid/changeable.rb, line 43 def changed_attributes @changed_attributes ||= {} end
Get all the changes for the document.
@example Get all the changes.
model.changes
@return [ Hash<String, Array<Object, Object> ] The changes.
# File lib/mongoid/changeable.rb, line 53 def changes changed.each_with_object({}) do |attr, changes| change = attribute_change(attr) changes[attr] = change if change end.with_indifferent_access end
Have any children (embedded documents) of this document changed?
@note This intentionally only considers children and not descendants.
@return [ true | false ] If any children have changed.
# File lib/mongoid/changeable.rb, line 33 def children_changed? _children.any?(&:changed?) end
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.
@example Move the changes to previous.
person.move_changes
# File lib/mongoid/changeable.rb, line 67 def move_changes @changes_before_last_save = @previous_changes @previous_changes = changes @attributes_before_last_save = @previous_attributes @previous_attributes = attributes.dup reset_atomic_updates! changed_attributes.clear end
Things that need to execute after a document has been persisted.
@example Handle post persistence.
document.post_persist
# File lib/mongoid/changeable.rb, line 80 def post_persist reset_persisted_descendants reset_attributes_before_type_cast move_changes end
Get the previous changes on the document.
@example Get the previous changes.
model.previous_changes
@return [ Hash<String, Array<Object, Object> ] The previous changes.
# File lib/mongoid/changeable.rb, line 92 def previous_changes @previous_changes ||= {} end
Remove a change from the dirty attributes hash. Used by the single field atomic updaters.
@example Remove a flagged change.
model.remove_change(:field)
@param [ Symbol | String ] name The name of the field.
# File lib/mongoid/changeable.rb, line 103 def remove_change(name) changed_attributes.delete(name.to_s) end
Returns the change to an attribute during the last save.
@param [ Symbol | String ] attr The name of the attribute.
@return [ Array<Object> | nil ] If the attribute was changed, returns
an array containing the original value and the saved value, otherwise nil.
# File lib/mongoid/changeable.rb, line 152 def saved_change_to_attribute(attr) attr = database_field_name(attr) previous_changes[attr] end
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.
@param [ String ] attr The name of the attribute. @param [ Object
] from The object the attribute was changed from (optional). @param [ Object
] to The object the attribute was changed to (optional).
@return [ true | false ] Whether the attribute has changed during the last save.
# File lib/mongoid/changeable.rb, line 167 def saved_change_to_attribute?(attr, from: Utils::PLACEHOLDER, to: Utils::PLACEHOLDER) changes = saved_change_to_attribute(attr) return false unless changes.is_a?(Array) return true if Utils.placeholder?(from) && Utils.placeholder?(to) return changes.first == from if Utils.placeholder?(to) return changes.last == to if Utils.placeholder?(from) changes.first == from && changes.last == to end
Gets all the new values for each of the changed fields, to be passed to a MongoDB $set modifier.
@example Get the setters for the atomic updates.
person = Person.new(:title => "Sir") person.title = "Madam" person.setters # returns { "title" => "Madam" }
@return [ Hash ] A Hash
of atomic setters.
# File lib/mongoid/changeable.rb, line 116 def setters mods = {} changes.each_pair do |name, changes| next unless changes old, new = changes field = fields[name] key = atomic_attribute_name(name) if field&.resizable? field.add_atomic_changes(self, name, key, mods, new, old) else mods[key] = new unless atomic_unsets.include?(key) end end mods end
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.
@param [ String ] attr The name of the attribute. @param **kwargs The optional keyword arguments.
@option **kwargs [ Object
] :from The object the attribute was changed from. @option **kwargs [ Object
] :to The object the attribute was changed to.
@return [ true | false ] Whether the attribute change the next time we save.
# File lib/mongoid/changeable.rb, line 190 def will_save_change_to_attribute?(attr, **kwargs) attribute_changed?(attr, **kwargs) end
Private Instance Methods
Get the old and new value for the provided attribute.
@example Get the attribute change.
model.attribute_change("name")
@param [ String ] attr The name of the attribute.
@return [ Array<Object> ] The old and new values.
# File lib/mongoid/changeable.rb, line 219 def attribute_change(attr) attr = database_field_name(attr) [ changed_attributes[attr], attributes[attr] ] if attribute_changed?(attr) end
Determine if a specific attribute has changed.
@example Has the attribute changed?
model.attribute_changed?("name")
@param [ String ] attr The name of the attribute. @param [ Object
] from The object the attribute was changed from (optional). @param [ Object
] to The object the attribute was changed to (optional).
@return [ true | false ] Whether the attribute has changed.
# File lib/mongoid/changeable.rb, line 257 def attribute_changed?(attr, from: ATTRIBUTE_UNCHANGED, to: ATTRIBUTE_UNCHANGED) attr = database_field_name(attr) return false unless changed_attributes.key?(attr) return false if changed_attributes[attr] == attributes[attr] return false if from != changed_attributes[attr] return false if to != attributes[attr] true end
Get whether or not the field has a different value from the default.
@example Is the field different from the default?
model.attribute_changed_from_default?
@param [ String ] attr The name of the attribute.
@return [ true | false ] If the attribute differs.
# File lib/mongoid/changeable.rb, line 275 def attribute_changed_from_default?(attr) return false unless (field = fields[attr]) attributes[attr] != field.eval_default(self) end
Get the previous attribute value that was changed before the document was saved.
It the document has not been saved yet, or was just loaded from database, this method returns nil for all attributes.
@param [ String ] attr The attribute name.
@return [ Object
| nil ] Attribute value before the document was saved,
or nil if the document has not been saved yet.
# File lib/mongoid/changeable.rb, line 302 def attribute_previously_was(attr) attr = database_field_name(attr) if previous_changes.key?(attr) previous_changes[attr].first else previous_attributes[attr] end end
Get the previous value for the attribute.
@example Get the previous value.
model.attribute_was("name")
@param [ String ] attr The attribute name.
# File lib/mongoid/changeable.rb, line 287 def attribute_was(attr) attr = database_field_name(attr) attribute_changed?(attr) ? changed_attributes[attr] : attributes[attr] end
Flag an attribute as going to change.
@example Flag the attribute.
model.attribute_will_change!("name")
@param [ String ] attr The name of the attribute.
@return [ Object
] The old value.
# File lib/mongoid/changeable.rb, line 319 def attribute_will_change!(attr) return if changed_attributes.key?(attr) changed_attributes[attr] = read_raw_attribute(attr).__deep_copy__ end
# File lib/mongoid/changeable.rb, line 207 def attributes_before_last_save @attributes_before_last_save ||= {} end
# File lib/mongoid/changeable.rb, line 203 def changes_before_last_save @changes_before_last_save ||= {} end
Get attributes of the document before the document was saved.
@return [ Hash ] Previous attributes
# File lib/mongoid/changeable.rb, line 199 def previous_attributes @previous_attributes ||= {} end
Set the attribute back to its old value.
@example Reset the attribute.
model.reset_attribute!("name")
@param [ String ] attr The name of the attribute.
@return [ Object
] The old value.
# File lib/mongoid/changeable.rb, line 333 def reset_attribute!(attr) attr = database_field_name(attr) attributes[attr] = changed_attributes.delete(attr) if attribute_changed?(attr) end
# File lib/mongoid/changeable.rb, line 338 def reset_attribute_to_default!(attr) attr = database_field_name(attr) if (field = fields[attr]) __send__("#{attr}=", field.eval_default(self)) else __send__("#{attr}=", nil) end end
# File lib/mongoid/changeable.rb, line 347 def reset_attributes_before_type_cast @attributes_before_type_cast = @attributes.dup end