Exemplo n.º 1
def _defaultvalueconstructorforfield(field):
  """returns a function which returns a default value for a field.

    field: fielddescriptor object for this field.

  the returned function has one argument:
    message: message instance containing this field, or a weakref proxy
      of same.

  that function in turn returns a default value for this field.  the default
    value may refer back to |message| via a weak reference.

  if field.label == _fielddescriptor.label_repeated:
    if field.has_default_value and field.default_value != []:
      raise valueerror('repeated field default value not empty list: %s' % (
    if field.cpp_type == _fielddescriptor.cpptype_message:
      # we can't look at _concrete_class yet since it might not have
      # been set.  (depends on order in which we initialize the classes).
      message_type = field.message_type
      def makerepeatedmessagedefault(message):
        return containers.repeatedcompositefieldcontainer(
            message._listener_for_children, field.message_type)
      return makerepeatedmessagedefault
      type_checker = type_checkers.gettypechecker(field.cpp_type, field.type)
      def makerepeatedscalardefault(message):
        return containers.repeatedscalarfieldcontainer(
            message._listener_for_children, type_checker)
      return makerepeatedscalardefault

  if field.cpp_type == _fielddescriptor.cpptype_message:
    # _concrete_class may not yet be initialized.
    message_type = field.message_type
    def makesubmessagedefault(message):
      result = message_type._concrete_class()
      return result
    return makesubmessagedefault

  def makescalardefault(message):
    # todo(protobuf-team): this may be broken since there may not be
    # default_value.  combine with has_default_value somehow.
    return field.default_value
  return makescalardefault
Exemplo n.º 2
  def __setitem__(self, extension_handle, value):
    """if extension_handle specifies a non-repeated, scalar extension
    field, sets the value of that field.

    _verifyextensionhandle(self._extended_message, extension_handle)

    if (extension_handle.label == _fielddescriptor.label_repeated or
        extension_handle.cpp_type == _fielddescriptor.cpptype_message):
      raise typeerror(
          'cannot assign to extension "%s" because it is a repeated or '
          'composite type.' % extension_handle.full_name)

    # it's slightly wasteful to lookup the type checker each time,
    # but we expect this to be a vanishingly uncommon case anyway.
    type_checker = type_checkers.gettypechecker(
        extension_handle.cpp_type, extension_handle.type)
    self._extended_message._fields[extension_handle] = value
Exemplo n.º 3
def _addpropertiesfornonrepeatedscalarfield(field, cls):
  """adds a public property for a nonrepeated, scalar protocol message field.
  clients can use this property to get and directly set the value of the field.
  note that when the client sets the value of a field by using this property,
  all necessary "has" bits are set as a side-effect, and we also perform

    field: a fielddescriptor for this field.
    cls: the class we're constructing.
  proto_field_name = field.name
  property_name = _propertyname(proto_field_name)
  type_checker = type_checkers.gettypechecker(field.cpp_type, field.type)
  default_value = field.default_value
  valid_values = set()

  def getter(self):
    # todo(protobuf-team): this may be broken since there may not be
    # default_value.  combine with has_default_value somehow.
    return self._fields.get(field, default_value)
  getter.__module__ = none
  getter.__doc__ = 'getter for %s.' % proto_field_name
  def setter(self, new_value):
    self._fields[field] = new_value
    # check _cached_byte_size_dirty inline to improve performance, since scalar
    # setters are called frequently.
    if not self._cached_byte_size_dirty:

  setter.__module__ = none
  setter.__doc__ = 'setter for %s.' % proto_field_name

  # add a property to encapsulate the getter/setter.
  doc = 'magic attribute generated for "%s" proto field.' % proto_field_name
  setattr(cls, property_name, property(getter, setter, doc=doc))