Module: ActiveModel::AttributeAssignment

Includes:
ForbiddenAttributesProtection
Included in:
API
Defined in:
lib/active_model/attribute_assignment.rb

Instance Method Summary collapse

Instance Method Details

#assign_attributes(new_attributes) ⇒ Object Also known as: attributes=

Allows you to set all the attributes by passing in a hash of attributes with keys matching the attribute names.

If the passed hash responds to permitted? method and the return value of this method is false an ActiveModel::ForbiddenAttributesError exception is raised.

class Cat
  include ActiveModel::AttributeAssignment
  attr_accessor :name, :status
end

cat = Cat.new
cat.assign_attributes(name: "Gorby", status: "yawning")
cat.name # => 'Gorby'
cat.status # => 'yawning'
cat.assign_attributes(status: "sleeping")
cat.name # => 'Gorby'
cat.status # => 'sleeping'


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# File 'lib/active_model/attribute_assignment.rb', line 28

def assign_attributes(new_attributes)
  unless new_attributes.respond_to?(:each_pair)
    raise ArgumentError, "When assigning attributes, you must pass a hash as an argument, #{new_attributes.class} passed."
  end
  return if new_attributes.empty?

  _assign_attributes(sanitize_for_mass_assignment(new_attributes))
end

#attribute_writer_missing(name, value) ⇒ Object

Like ‘BasicObject#method_missing`, `#attribute_writer_missing` is invoked when `#assign_attributes` is passed an unknown attribute name.

By default, ‘#attribute_writer_missing` raises an UnknownAttributeError.

class Rectangle
  include ActiveModel::AttributeAssignment

  attr_accessor :length, :width

  def attribute_writer_missing(name, value)
    Rails.logger.warn "Tried to assign to unknown attribute #{name}"
  end
end

rectangle = Rectangle.new
rectangle.assign_attributes(height: 10) # => Logs "Tried to assign to unknown attribute 'height'"


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# File 'lib/active_model/attribute_assignment.rb', line 56

def attribute_writer_missing(name, value)
  raise UnknownAttributeError.new(self, name)
end