diff options
Diffstat (limited to 'activerecord/lib/active_record/attribute_methods.rb')
-rw-r--r-- | activerecord/lib/active_record/attribute_methods.rb | 202 |
1 files changed, 175 insertions, 27 deletions
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb index d7bfaa5655..3e27e85f02 100644 --- a/activerecord/lib/active_record/attribute_methods.rb +++ b/activerecord/lib/active_record/attribute_methods.rb @@ -7,35 +7,59 @@ module ActiveRecord extend ActiveSupport::Concern include ActiveModel::AttributeMethods + included do + include Read + include Write + include BeforeTypeCast + include Query + include PrimaryKey + include TimeZoneConversion + include Dirty + include Serialization + + # 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)). + # (Alias for the protected read_attribute method). + def [](attr_name) + read_attribute(attr_name) + end + + # Updates the attribute identified by <tt>attr_name</tt> with the specified +value+. + # (Alias for the protected write_attribute method). + def []=(attr_name, value) + write_attribute(attr_name, value) + end + end + module ClassMethods # Generates all the attribute related methods for columns in the database # accessors, mutators and query methods. def define_attribute_methods - return if attribute_methods_generated? - - if base_class == self + # Use a mutex; we don't want two thread simaltaneously trying to define + # attribute methods. + @attribute_methods_mutex.synchronize do + return if attribute_methods_generated? + superclass.define_attribute_methods unless self == base_class super(column_names) @attribute_methods_generated = true - else - base_class.define_attribute_methods end end def attribute_methods_generated? - if base_class == self - @attribute_methods_generated ||= false - else - base_class.attribute_methods_generated? - end + @attribute_methods_generated ||= false end - def undefine_attribute_methods(*args) - if base_class == self - super - @attribute_methods_generated = false - else - base_class.undefine_attribute_methods(*args) - end + # We will define the methods as instance methods, but will call them as singleton + # methods. This allows us to use method_defined? to check if the method exists, + # which is fast and won't give any false positives from the ancestors (because + # there are no ancestors). + def generated_external_attribute_methods + @generated_external_attribute_methods ||= Module.new { extend self } + end + + def undefine_attribute_methods + super if attribute_methods_generated? + @attribute_methods_generated = false end def instance_method_already_implemented?(method_name) @@ -43,19 +67,46 @@ module ActiveRecord raise DangerousAttributeError, "#{method_name} is defined by ActiveRecord" end - super + if [Base, Model].include?(active_record_super) + super + else + # If B < A and A defines its own attribute method, then we don't want to overwrite that. + defined = method_defined_within?(method_name, superclass, superclass.generated_attribute_methods) + defined && !ActiveRecord::Base.method_defined?(method_name) || super + end end # A method name is 'dangerous' if it is already defined by Active Record, but # not by any ancestors. (So 'puts' is not dangerous but 'save' is.) - def dangerous_attribute_method?(method_name) - active_record = ActiveRecord::Base - superclass = ActiveRecord::Base.superclass + def dangerous_attribute_method?(name) + method_defined_within?(name, Base) + end + + def method_defined_within?(name, klass, sup = klass.superclass) + if klass.method_defined?(name) || klass.private_method_defined?(name) + if sup.method_defined?(name) || sup.private_method_defined?(name) + klass.instance_method(name).owner != sup.instance_method(name).owner + else + true + end + else + false + end + end - (active_record.method_defined?(method_name) || - active_record.private_method_defined?(method_name)) && - !superclass.method_defined?(method_name) && - !superclass.private_method_defined?(method_name) + def attribute_method?(attribute) + super || (table_exists? && column_names.include?(attribute.to_s.sub(/=$/, ''))) + end + + # Returns an array of column names as strings if it's not + # an abstract class and table exists. + # Otherwise it returns an empty array. + def attribute_names + @attribute_names ||= if !abstract_class? && table_exists? + column_names + else + [] + end end end @@ -94,9 +145,106 @@ module ActiveRecord super end + # Returns true if the given attribute is in the attributes hash + def has_attribute?(attr_name) + @attributes.has_key?(attr_name.to_s) + end + + # Returns an array of names for the attributes available on this object. + def attribute_names + @attributes.keys + end + + # Returns a hash of all the attributes with their names as keys and the values of the attributes as values. + def attributes + Hash[@attributes.map { |name, _| [name, read_attribute(name)] }] + end + + # Returns an <tt>#inspect</tt>-like string for the value of the + # attribute +attr_name+. String attributes are truncated upto 50 + # characters, and Date and Time attributes are returned in the + # <tt>:db</tt> format. Other attributes return the value of + # <tt>#inspect</tt> without modification. + # + # person = Person.create!(:name => "David Heinemeier Hansson " * 3) + # + # person.attribute_for_inspect(:name) + # # => '"David Heinemeier Hansson David Heinemeier Hansson D..."' + # + # person.attribute_for_inspect(:created_at) + # # => '"2009-01-12 04:48:57"' + def attribute_for_inspect(attr_name) + value = read_attribute(attr_name) + + if value.is_a?(String) && value.length > 50 + "#{value[0..50]}...".inspect + elsif value.is_a?(Date) || value.is_a?(Time) + %("#{value.to_s(:db)}") + else + value.inspect + end + end + + # Returns true if the specified +attribute+ has been set by the user or by a database load and is neither + # nil nor empty? (the latter only applies to objects that respond to empty?, most notably Strings). + def attribute_present?(attribute) + value = read_attribute(attribute) + !value.nil? || (value.respond_to?(:empty?) && !value.empty?) + end + + # Returns the column object for the named attribute. + def column_for_attribute(name) + # FIXME: should this return a null object for columns that don't exist? + self.class.columns_hash[name.to_s] + end + protected - def attribute_method?(attr_name) - attr_name == 'id' || (defined?(@attributes) && @attributes.include?(attr_name)) + + def clone_attributes(reader_method = :read_attribute, attributes = {}) + attribute_names.each do |name| + attributes[name] = clone_attribute_value(reader_method, name) end + attributes + end + + def clone_attribute_value(reader_method, attribute_name) + value = send(reader_method, attribute_name) + value.duplicable? ? value.clone : value + rescue TypeError, NoMethodError + value + end + + # Returns a copy of the attributes hash where all the values have been safely quoted for use in + # an Arel insert/update method. + def arel_attributes_values(include_primary_key = true, include_readonly_attributes = true, attribute_names = @attributes.keys) + attrs = {} + klass = self.class + arel_table = klass.arel_table + + attribute_names.each do |name| + if (column = column_for_attribute(name)) && (include_primary_key || !column.primary) + + if include_readonly_attributes || !self.class.readonly_attributes.include?(name) + + value = if klass.serialized_attributes.include?(name) + @attributes[name].serialized_value + else + # FIXME: we need @attributes to be used consistently. + # If the values stored in @attributes were already type + # casted, this code could be simplified + read_attribute(name) + end + + attrs[arel_table[name]] = value + end + end + end + + attrs + end + + def attribute_method?(attr_name) + defined?(@attributes) && @attributes.include?(attr_name) + end end end |