module DatastaxRails::AttributeMethods::Dirty
Change tracking for attributes. Builds on ActiveModel::Dirty in order to reset changes on save.
Public Instance Methods
reload(*)
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reload
the record and clears changed attributes.
Calls superclass method
# File lib/datastax_rails/attribute_methods/dirty.rb, line 39 def reload(*) super.tap do @previously_changed.clear @changed_attributes.clear end end
write_attribute(attr, value)
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Calls superclass method
# File lib/datastax_rails/attribute_methods/dirty.rb, line 46 def write_attribute(attr, value) attr = attr.to_s loaded_attributes[attr] = true # The attribute already has an unsaved change. if attribute_changed?(attr) old = @changed_attributes[attr] @changed_attributes.delete(attr) unless _field_changed?(attr, old, value) else old = clone_attribute_value(:read_attribute, attr) @changed_attributes[attr] = old if _field_changed?(attr, old, value) end super end
Private Instance Methods
_field_changed?(attr, old, value)
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# File lib/datastax_rails/attribute_methods/dirty.rb, line 64 def _field_changed?(attr, old, value) if (column = column_for_attribute(attr)) if column.number? && (changes_from_nil_to_empty_string?(column, old, value) || changes_from_zero_to_string?(old, value)) value = nil else value = column.type_cast(value, self) end end old != value end
changes_from_nil_to_empty_string?(_column, old, value)
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# File lib/datastax_rails/attribute_methods/dirty.rb, line 77 def changes_from_nil_to_empty_string?(_column, old, value) # We don't record it as a change if the value changes from nil to ''. # If an old value of 0 is set to '' we want this to get changed to nil as otherwise it'll # be typecast back to 0 (''.to_i => 0) (old.nil? || old == 0) && value.blank? end
changes_from_zero_to_string?(old, value)
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# File lib/datastax_rails/attribute_methods/dirty.rb, line 84 def changes_from_zero_to_string?(old, value) # For columns with old 0 and value non-empty string old == 0 && value.is_a?(String) && value.present? && non_zero?(value) end
non_zero?(value)
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# File lib/datastax_rails/attribute_methods/dirty.rb, line 89 def non_zero?(value) value !~ /\A0+(\.0+)?\z/ end