Source code for dhcpkit.tests.ipv6.options.test_relay_message_option

Test the RelayMessageOption implementation
import unittest

from dhcpkit.ipv6.message_registry import message_registry
from dhcpkit.ipv6.messages import ClientServerMessage, UnknownMessage
from dhcpkit.ipv6.options import RelayMessageOption
from dhcpkit.tests.ipv6.options import test_option

# A dummy option that may not be in a RelayMessageOption
[docs]class NonRelayableMessage(UnknownMessage): """ A message that can not be relayed """ pass
# Add the constraint to disallow putting it in a RelayMessageOption RelayMessageOption.add_may_contain(NonRelayableMessage, max_occurrence=0) # A dummy message that has the wrong length
[docs]class WeirdLengthMessage(ClientServerMessage): """ An option that returns an incorrect length, to test error handling """ message_type = 254
[docs] def load_from(self, buffer: bytes, offset: int = 0, length: int = None): """ Load the internal state of this object from the given buffer. The buffer may contain more data after the structured element is parsed. This data is ignored. :param buffer: The buffer to read data from :param offset: The offset in the buffer where to start reading :param length: The amount of data we are allowed to read from the buffer :return: The number of bytes used from the buffer """ return 4
[docs]class RelayMessageOptionTestCase(test_option.OptionTestCase):
[docs] def setUp(self): self.option_bytes = bytes.fromhex('00090017ff') + b'ThisIsAnUnknownMessage' self.option_object = RelayMessageOption(relayed_message=UnknownMessage(255, b'ThisIsAnUnknownMessage')) self.parse_option()
[docs] def test_validate_relayed_message(self): self.option.relayed_message = None with self.assertRaisesRegex(ValueError, 'IPv6 DHCP message'): self.option.validate() self.option.relayed_message = NonRelayableMessage(255, b'ThisIsAnUnknownMessage') with self.assertRaisesRegex(ValueError, 'cannot contain'): self.option.validate()
[docs] def test_bad_message_length(self): # Add a fake message type to the registry message_registry[254] = WeirdLengthMessage with self.assertRaisesRegex(ValueError, 'different length'): RelayMessageOption.parse(bytes.fromhex('00090006fe1234567890')) # And clean it up again del message_registry[254]
if __name__ == '__main__': # pragma: no cover unittest.main()