module ActiveRecord::AttributeAssignment

Public Instance Methods

assign_attributes(new_attributes) click to toggle source

Allows you to set all the attributes by passing in a hash of attributes with keys matching the attribute names (which again matches the column names).

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

cat = Cat.new(name: "Gorby", status: "yawning")
cat.attributes # =>  { "name" => "Gorby", "status" => "yawning", "created_at" => nil, "updated_at" => nil}
cat.assign_attributes(status: "sleeping")
cat.attributes # =>  { "name" => "Gorby", "status" => "sleeping", "created_at" => nil, "updated_at" => nil }

New attributes will be persisted in the database when the object is saved.

Aliased to attributes=.

# File lib/active_record/attribute_assignment.rb, line 23
def assign_attributes(new_attributes)
  if !new_attributes.respond_to?(:stringify_keys)
    raise ArgumentError, "When assigning attributes, you must pass a hash as an argument."
  end
  return if new_attributes.blank?

  attributes                  = new_attributes.stringify_keys
  multi_parameter_attributes  = []
  nested_parameter_attributes = []

  attributes = sanitize_for_mass_assignment(attributes)

  attributes.each do |k, v|
    if k.include?("(")
      multi_parameter_attributes << [ k, v ]
    elsif v.is_a?(Hash)
      nested_parameter_attributes << [ k, v ]
    else
      _assign_attribute(k, v)
    end
  end

  assign_nested_parameter_attributes(nested_parameter_attributes) unless nested_parameter_attributes.empty?
  assign_multiparameter_attributes(multi_parameter_attributes) unless multi_parameter_attributes.empty?
end
Also aliased as: attributes=
attributes=(new_attributes)
Alias for: assign_attributes

Private Instance Methods

_assign_attribute(k, v) click to toggle source
# File lib/active_record/attribute_assignment.rb, line 53
def _assign_attribute(k, v)
  public_send("#{k}=", v)
rescue NoMethodError, NameError
  if respond_to?("#{k}=")
    raise
  else
    raise UnknownAttributeError.new(self, k)
  end
end
assign_multiparameter_attributes(pairs) click to toggle source

Instantiates objects for all attribute classes that needs more than one constructor parameter. This is done by calling new on the column type or aggregation type (through composed_of) object with these parameters. So having the pairs written_on(1) = “2004”, written_on(2) = “6”, written_on(3) = “24”, will instantiate written_on (a date type) with Date.new(“2004”, “6”, “24”). You can also specify a typecast character in the parentheses to have the parameters typecasted before they're used in the constructor. Use i for Fixnum and f for Float. If all the values for a given attribute are empty, the attribute will be set to nil.

# File lib/active_record/attribute_assignment.rb, line 74
def assign_multiparameter_attributes(pairs)
  execute_callstack_for_multiparameter_attributes(
    extract_callstack_for_multiparameter_attributes(pairs)
  )
end
assign_nested_parameter_attributes(pairs) click to toggle source

Assign any deferred nested attributes after the base attributes have been set.

# File lib/active_record/attribute_assignment.rb, line 64
def assign_nested_parameter_attributes(pairs)
  pairs.each { |k, v| _assign_attribute(k, v) }
end
execute_callstack_for_multiparameter_attributes(callstack) click to toggle source
# File lib/active_record/attribute_assignment.rb, line 80
def execute_callstack_for_multiparameter_attributes(callstack)
  errors = []
  callstack.each do |name, values_with_empty_parameters|
    begin
      send("#{name}=", MultiparameterAttribute.new(self, name, values_with_empty_parameters).read_value)
    rescue => ex
      errors << AttributeAssignmentError.new("error on assignment #{values_with_empty_parameters.values.inspect} to #{name} (#{ex.message})", ex, name)
    end
  end
  unless errors.empty?
    error_descriptions = errors.map { |ex| ex.message }.join(",")
    raise MultiparameterAssignmentErrors.new(errors), "#{errors.size} error(s) on assignment of multiparameter attributes [#{error_descriptions}]"
  end
end
extract_callstack_for_multiparameter_attributes(pairs) click to toggle source
# File lib/active_record/attribute_assignment.rb, line 95
def extract_callstack_for_multiparameter_attributes(pairs)
  attributes = {}

  pairs.each do |(multiparameter_name, value)|
    attribute_name = multiparameter_name.split("(").first
    attributes[attribute_name] ||= {}

    parameter_value = value.empty? ? nil : type_cast_attribute_value(multiparameter_name, value)
    attributes[attribute_name][find_parameter_position(multiparameter_name)] ||= parameter_value
  end

  attributes
end
find_parameter_position(multiparameter_name) click to toggle source
# File lib/active_record/attribute_assignment.rb, line 113
def find_parameter_position(multiparameter_name)
  multiparameter_name.scan(/\(([0-9]*).*\)/).first.first.to_i
end
type_cast_attribute_value(multiparameter_name, value) click to toggle source
# File lib/active_record/attribute_assignment.rb, line 109
def type_cast_attribute_value(multiparameter_name, value)
  multiparameter_name =~ /\([0-9]*([if])\)/ ? value.send("to_" + $1) : value
end