require 'active_model/forbidden_attributes_protection'
module ActiveRecord
module AttributeAssignment
extend ActiveSupport::Concern
include ActiveModel::AttributeAssignment
def _assign_attributes(attributes) # :nodoc:
multi_parameter_attributes = {}
nested_parameter_attributes = {}
attributes.each do |k, v|
if k.include?("(")
multi_parameter_attributes[k] = attributes.delete(k)
elsif v.is_a?(Hash)
nested_parameter_attributes[k] = attributes.delete(k)
end
end
super(attributes)
assign_nested_parameter_attributes(nested_parameter_attributes) unless nested_parameter_attributes.empty?
assign_multiparameter_attributes(multi_parameter_attributes) unless multi_parameter_attributes.empty?
end
# Alias for `assign_attributes`. See +ActiveModel::AttributeAssignment+
def attributes=(attributes)
assign_attributes(attributes)
end
private
# Assign any deferred nested attributes after the base attributes have been set.
def assign_nested_parameter_attributes(pairs)
pairs.each { |k, v| _assign_attribute(k, v) }
end
# 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+.
def assign_multiparameter_attributes(pairs)
execute_callstack_for_multiparameter_attributes(
extract_callstack_for_multiparameter_attributes(pairs)
)
end
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(&:message).join(",")
raise MultiparameterAssignmentErrors.new(errors), "#{errors.size} error(s) on assignment of multiparameter attributes [#{error_descriptions}]"
end
end
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
def type_cast_attribute_value(multiparameter_name, value)
multiparameter_name =~ /\([0-9]*([if])\)/ ? value.send("to_" + $1) : value
end
def find_parameter_position(multiparameter_name)
multiparameter_name.scan(/\(([0-9]*).*\)/).first.first.to_i
end
class MultiparameterAttribute #:nodoc:
attr_reader :object, :name, :values, :cast_type
def initialize(object, name, values)
@object = object
@name = name
@values = values
end
def read_value
return if values.values.compact.empty?
@cast_type = object.type_for_attribute(name)
klass = cast_type.klass
if klass == Time
read_time
elsif klass == Date
read_date
else
read_other
end
end
private
def instantiate_time_object(set_values)
if object.class.send(:create_time_zone_conversion_attribute?, name, cast_type)
Time.zone.local(*set_values)
else
Time.send(object.class.default_timezone, *set_values)
end
end
def read_time
# If column is a :time (and not :date or :datetime) there is no need to validate if
# there are year/month/day fields
if cast_type.type == :time
# if the column is a time set the values to their defaults as January 1, 1970, but only if they're nil
{ 1 => 1970, 2 => 1, 3 => 1 }.each do |key,value|
values[key] ||= value
end
else
# else column is a timestamp, so if Date bits were not provided, error
validate_required_parameters!([1,2,3])
# If Date bits were provided but blank, then return nil
return if blank_date_parameter?
end
max_position = extract_max_param(6)
set_values = values.values_at(*(1..max_position))
# If Time bits are not there, then default to 0
(3..5).each { |i| set_values[i] = set_values[i].presence || 0 }
instantiate_time_object(set_values)
end
def read_date
return if blank_date_parameter?
set_values = values.values_at(1,2,3)
begin
Date.new(*set_values)
rescue ArgumentError # if Date.new raises an exception on an invalid date
instantiate_time_object(set_values).to_date # we instantiate Time object and convert it back to a date thus using Time's logic in handling invalid dates
end
end
def read_other
max_position = extract_max_param
positions = (1..max_position)
validate_required_parameters!(positions)
values.slice(*positions)
end
# Checks whether some blank date parameter exists. Note that this is different
# than the validate_required_parameters! method, since it just checks for blank
# positions instead of missing ones, and does not raise in case one blank position
# exists. The caller is responsible to handle the case of this returning true.
def blank_date_parameter?
(1..3).any? { |position| values[position].blank? }
end
# If some position is not provided, it errors out a missing parameter exception.
def validate_required_parameters!(positions)
if missing_parameter = positions.detect { |position| !values.key?(position) }
raise ArgumentError.new("Missing Parameter - #{name}(#{missing_parameter})")
end
end
def extract_max_param(upper_cap = 100)
[values.keys.max, upper_cap].min
end
end
end
end
