diff options
Diffstat (limited to 'activerecord/lib/active_record/attribute_methods.rb')
| -rw-r--r-- | activerecord/lib/active_record/attribute_methods.rb | 372 |
1 files changed, 12 insertions, 360 deletions
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb index ecd2d57a5a..ab7ad34b9e 100644 --- a/activerecord/lib/active_record/attribute_methods.rb +++ b/activerecord/lib/active_record/attribute_methods.rb @@ -3,100 +3,13 @@ require 'active_support/core_ext/enumerable' module ActiveRecord module AttributeMethods #:nodoc: extend ActiveSupport::Concern + include ActiveModel::AttributeMethods - DEFAULT_SUFFIXES = %w(= ? _before_type_cast) - ATTRIBUTE_TYPES_CACHED_BY_DEFAULT = [:datetime, :timestamp, :time, :date] - - included do - attribute_method_suffix(*DEFAULT_SUFFIXES) - - cattr_accessor :attribute_types_cached_by_default, :instance_writer => false - self.attribute_types_cached_by_default = ATTRIBUTE_TYPES_CACHED_BY_DEFAULT - - cattr_accessor :time_zone_aware_attributes, :instance_writer => false - self.time_zone_aware_attributes = false - - class_inheritable_accessor :skip_time_zone_conversion_for_attributes, :instance_writer => false - self.skip_time_zone_conversion_for_attributes = [] - end - - # Declare and check for suffixed attribute methods. module ClassMethods - # Declares a method available for all attributes with the given suffix. - # Uses +method_missing+ and <tt>respond_to?</tt> to rewrite the method - # - # #{attr}#{suffix}(*args, &block) - # - # to - # - # attribute#{suffix}(#{attr}, *args, &block) - # - # An <tt>attribute#{suffix}</tt> instance method must exist and accept at least - # the +attr+ argument. - # - # For example: - # - # class Person < ActiveRecord::Base - # attribute_method_suffix '_changed?' - # - # private - # def attribute_changed?(attr) - # ... - # end - # end - # - # person = Person.find(1) - # person.name_changed? # => false - # person.name = 'Hubert' - # person.name_changed? # => true - def attribute_method_suffix(*suffixes) - attribute_method_suffixes.concat suffixes - rebuild_attribute_method_regexp - end - - # Returns MatchData if method_name is an attribute method. - def match_attribute_method?(method_name) - rebuild_attribute_method_regexp unless defined?(@@attribute_method_regexp) && @@attribute_method_regexp - @@attribute_method_regexp.match(method_name) - end - - - # Contains the names of the generated attribute methods. - def generated_methods #:nodoc: - @generated_methods ||= Set.new - end - - def generated_methods? - !generated_methods.empty? - end - # Generates all the attribute related methods for columns in the database # accessors, mutators and query methods. def define_attribute_methods - return if generated_methods? - columns_hash.each do |name, column| - unless instance_method_already_implemented?(name) - if self.serialized_attributes[name] - define_read_method_for_serialized_attribute(name) - elsif create_time_zone_conversion_attribute?(name, column) - define_read_method_for_time_zone_conversion(name) - else - define_read_method(name.to_sym, name, column) - end - end - - unless instance_method_already_implemented?("#{name}=") - if create_time_zone_conversion_attribute?(name, column) - define_write_method_for_time_zone_conversion(name) - else - define_write_method(name.to_sym) - end - end - - unless instance_method_already_implemented?("#{name}?") - define_question_method(name) - end - end + super(columns_hash.keys) end # Checks whether the method is defined in the model or any of its subclasses @@ -104,296 +17,35 @@ module ActiveRecord # method is defined by Active Record though. def instance_method_already_implemented?(method_name) method_name = method_name.to_s - return true if method_name =~ /^id(=$|\?$|$)/ @_defined_class_methods ||= ancestors.first(ancestors.index(ActiveRecord::Base)).sum([]) { |m| m.public_instance_methods(false) | m.private_instance_methods(false) | m.protected_instance_methods(false) }.map {|m| m.to_s }.to_set @@_defined_activerecord_methods ||= (ActiveRecord::Base.public_instance_methods(false) | ActiveRecord::Base.private_instance_methods(false) | ActiveRecord::Base.protected_instance_methods(false)).map{|m| m.to_s }.to_set raise DangerousAttributeError, "#{method_name} is defined by ActiveRecord" if @@_defined_activerecord_methods.include?(method_name) @_defined_class_methods.include?(method_name) end - - alias :define_read_methods :define_attribute_methods - - # +cache_attributes+ allows you to declare which converted attribute values should - # be cached. Usually caching only pays off for attributes with expensive conversion - # methods, like time related columns (e.g. +created_at+, +updated_at+). - def cache_attributes(*attribute_names) - attribute_names.each {|attr| cached_attributes << attr.to_s} - end - - # Returns the attributes which are cached. By default time related columns - # with datatype <tt>:datetime, :timestamp, :time, :date</tt> are cached. - def cached_attributes - @cached_attributes ||= - columns.select{|c| attribute_types_cached_by_default.include?(c.type)}.map{|col| col.name}.to_set - end - - # Returns +true+ if the provided attribute is being cached. - def cache_attribute?(attr_name) - cached_attributes.include?(attr_name) - end - - private - - # Suffixes a, ?, c become regexp /(a|\?|c)$/ - def rebuild_attribute_method_regexp - suffixes = attribute_method_suffixes.map { |s| Regexp.escape(s) } - @@attribute_method_regexp = /(#{suffixes.join('|')})$/.freeze - end - - # Default to =, ?, _before_type_cast - def attribute_method_suffixes - @@attribute_method_suffixes ||= [] - end - - def create_time_zone_conversion_attribute?(name, column) - time_zone_aware_attributes && !skip_time_zone_conversion_for_attributes.include?(name.to_sym) && [:datetime, :timestamp].include?(column.type) - end - - # Define an attribute reader method. Cope with nil column. - def define_read_method(symbol, attr_name, column) - cast_code = column.type_cast_code('v') if column - access_code = cast_code ? "(v=@attributes['#{attr_name}']) && #{cast_code}" : "@attributes['#{attr_name}']" - - unless attr_name.to_s == self.primary_key.to_s - access_code = access_code.insert(0, "missing_attribute('#{attr_name}', caller) unless @attributes.has_key?('#{attr_name}'); ") - end - - if cache_attribute?(attr_name) - access_code = "@attributes_cache['#{attr_name}'] ||= (#{access_code})" - end - evaluate_attribute_method attr_name, "def #{symbol}; #{access_code}; end" - end - - # Define read method for serialized attribute. - def define_read_method_for_serialized_attribute(attr_name) - evaluate_attribute_method attr_name, "def #{attr_name}; unserialize_attribute('#{attr_name}'); end" - end - - # Defined for all +datetime+ and +timestamp+ attributes when +time_zone_aware_attributes+ are enabled. - # This enhanced read method automatically converts the UTC time stored in the database to the time zone stored in Time.zone. - def define_read_method_for_time_zone_conversion(attr_name) - method_body = <<-EOV - def #{attr_name}(reload = false) - cached = @attributes_cache['#{attr_name}'] - return cached if cached && !reload - time = read_attribute('#{attr_name}') - @attributes_cache['#{attr_name}'] = time.acts_like?(:time) ? time.in_time_zone : time - end - EOV - evaluate_attribute_method attr_name, method_body - end - - # Defines a predicate method <tt>attr_name?</tt>. - def define_question_method(attr_name) - evaluate_attribute_method attr_name, "def #{attr_name}?; query_attribute('#{attr_name}'); end", "#{attr_name}?" - end - - def define_write_method(attr_name) - evaluate_attribute_method attr_name, "def #{attr_name}=(new_value);write_attribute('#{attr_name}', new_value);end", "#{attr_name}=" - end - - # Defined for all +datetime+ and +timestamp+ attributes when +time_zone_aware_attributes+ are enabled. - # This enhanced write method will automatically convert the time passed to it to the zone stored in Time.zone. - def define_write_method_for_time_zone_conversion(attr_name) - method_body = <<-EOV - def #{attr_name}=(time) - unless time.acts_like?(:time) - time = time.is_a?(String) ? Time.zone.parse(time) : time.to_time rescue time - end - time = time.in_time_zone rescue nil if time - write_attribute(:#{attr_name}, time) - end - EOV - evaluate_attribute_method attr_name, method_body, "#{attr_name}=" - end - - # Evaluate the definition for an attribute related method - def evaluate_attribute_method(attr_name, method_definition, method_name=attr_name) - - unless method_name.to_s == primary_key.to_s - generated_methods << method_name - end - - begin - class_eval(method_definition, __FILE__, __LINE__) - rescue SyntaxError => err - generated_methods.delete(attr_name) - if logger - logger.warn "Exception occurred during reader method compilation." - logger.warn "Maybe #{attr_name} is not a valid Ruby identifier?" - logger.warn err.message - end - end - end - end # ClassMethods - + end - # Allows access to the object attributes, which are held in the <tt>@attributes</tt> hash, as though they - # were first-class methods. So a Person class with a name attribute can use Person#name and - # Person#name= and never directly use the attributes hash -- except for multiple assigns with - # ActiveRecord#attributes=. A Milestone class can also ask Milestone#completed? to test that - # the completed attribute is not +nil+ or 0. - # - # It's also possible to instantiate related objects, so a Client class belonging to the clients - # table with a +master_id+ foreign key can instantiate master through Client#master. def method_missing(method_id, *args, &block) - method_name = method_id.to_s - # If we haven't generated any methods yet, generate them, then # see if we've created the method we're looking for. - if !self.class.generated_methods? + if !self.class.attribute_methods_generated? self.class.define_attribute_methods + method_name = method_id.to_s guard_private_attribute_method!(method_name, args) - if self.class.generated_methods.include?(method_name) + if self.class.generated_attribute_methods.instance_methods.include?(method_name) return self.send(method_id, *args, &block) end end - - guard_private_attribute_method!(method_name, args) - if self.class.primary_key.to_s == method_name - id - elsif md = self.class.match_attribute_method?(method_name) - attribute_name, method_type = md.pre_match, md.to_s - if @attributes.include?(attribute_name) - __send__("attribute#{method_type}", attribute_name, *args, &block) - else - super - end - elsif @attributes.include?(method_name) - read_attribute(method_name) - else - super - end - end - - # Returns the value of the attribute identified by <tt>attr_name</tt> after it has been typecast (for example, - # "2004-12-12" in a data column is cast to a date object, like Date.new(2004, 12, 12)). - def read_attribute(attr_name) - attr_name = attr_name.to_s - if !(value = @attributes[attr_name]).nil? - if column = column_for_attribute(attr_name) - if unserializable_attribute?(attr_name, column) - unserialize_attribute(attr_name) - else - column.type_cast(value) - end - else - value - end - else - nil - end - end - - def read_attribute_before_type_cast(attr_name) - @attributes[attr_name] - end - - # Returns true if the attribute is of a text column and marked for serialization. - def unserializable_attribute?(attr_name, column) - column.text? && self.class.serialized_attributes[attr_name] - end - - # Returns the unserialized object of the attribute. - def unserialize_attribute(attr_name) - unserialized_object = object_from_yaml(@attributes[attr_name]) - - if unserialized_object.is_a?(self.class.serialized_attributes[attr_name]) || unserialized_object.nil? - @attributes.frozen? ? unserialized_object : @attributes[attr_name] = unserialized_object - else - raise SerializationTypeMismatch, - "#{attr_name} was supposed to be a #{self.class.serialized_attributes[attr_name]}, but was a #{unserialized_object.class.to_s}" - end - end - - - # Updates the attribute identified by <tt>attr_name</tt> with the specified +value+. Empty strings for fixnum and float - # columns are turned into +nil+. - def write_attribute(attr_name, value) - attr_name = attr_name.to_s - @attributes_cache.delete(attr_name) - if (column = column_for_attribute(attr_name)) && column.number? - @attributes[attr_name] = convert_number_column_value(value) - else - @attributes[attr_name] = value - end + super end - - def query_attribute(attr_name) - unless value = read_attribute(attr_name) - false - else - column = self.class.columns_hash[attr_name] - if column.nil? - if Numeric === value || value !~ /[^0-9]/ - !value.to_i.zero? - else - return false if ActiveRecord::ConnectionAdapters::Column::FALSE_VALUES.include?(value) - !value.blank? - end - elsif column.number? - !value.zero? - else - !value.blank? - end - end - end - - # A Person object with a name attribute can ask <tt>person.respond_to?(:name)</tt>, - # <tt>person.respond_to?(:name=)</tt>, and <tt>person.respond_to?(:name?)</tt> - # which will all return +true+. - alias :respond_to_without_attributes? :respond_to? - def respond_to?(method, include_private_methods = false) - method_name = method.to_s - if super - return true - elsif !include_private_methods && super(method, true) - # If we're here than we haven't found among non-private methods - # but found among all methods. Which means that given method is private. - return false - elsif !self.class.generated_methods? - self.class.define_attribute_methods - if self.class.generated_methods.include?(method_name) - return true - end - end - - if @attributes.nil? - return super - elsif @attributes.include?(method_name) - return true - elsif md = self.class.match_attribute_method?(method_name) - return true if @attributes.include?(md.pre_match) - end + def respond_to?(*args) + self.class.define_attribute_methods super end - private - # prevent method_missing from calling private methods with #send - def guard_private_attribute_method!(method_name, args) - if self.class.private_method_defined?(method_name) - raise NoMethodError.new("Attempt to call private method", method_name, args) - end - end - - def missing_attribute(attr_name, stack) - raise ActiveRecord::MissingAttributeError, "missing attribute: #{attr_name}", stack - end - - # Handle *? for method_missing. - def attribute?(attribute_name) - query_attribute(attribute_name) - end - - # Handle *= for method_missing. - def attribute=(attribute_name, value) - write_attribute(attribute_name, value) - end - - # Handle *_before_type_cast for method_missing. - def attribute_before_type_cast(attribute_name) - read_attribute_before_type_cast(attribute_name) + protected + def attribute_method?(attr_name) + attr_name == 'id' || attributes.include?(attr_name) end end end |