Synnefo

                                      related_name='neutron_machines')

    def __unicode__(self):

        return "<Network: %s>" % str(self.id)

    @property

    def backend_id(self):

        """Return the backend id by prepending backend-prefix."""

        if not self.id:

            raise Network.InvalidBackendIdError("self.id is None")

        return "%snet-%s" % (settings.BACKEND_PREFIX_ID, str(self.id))

    @property

    def backend_tag(self):

        """Return the network tag to be used in backend

        """

        if self.tags:

            return self.tags.split(',')

        else:

            return []

    def create_backend_network(self, backend=None):

        """Create corresponding BackendNetwork entries."""

        backends = [backend] if backend else\

            Backend.objects.filter(offline=False)

        for backend in backends:

            backend_exists =\

                BackendNetwork.objects.filter(backend=backend, network=self)\

                                      .exists()

            if not backend_exists:

                BackendNetwork.objects.create(backend=backend, network=self)

    def get_pool(self, with_lock=True):

        if not self.pool_id:

            self.pool = IPPoolTable.objects.create(available_map='',

                                                   reserved_map='',

                                                   size=0)

            self.save()

        objects = IPPoolTable.objects

        if with_lock:

            objects = objects.select_for_update()

        return objects.get(id=self.pool_id).pool

    def reserve_address(self, address):

        pool = self.get_pool()

        pool.reserve(address)

        pool.save()

    def release_address(self, address):

        pool = self.get_pool()

        pool.put(address)

        pool.save()

    class InvalidBackendIdError(Exception):

        def __init__(self, value):

            self.value = value

        def __str__(self):

            return repr(self.value)

    class InvalidBackendMsgError(Exception):

        def __init__(self, opcode, status):

            self.opcode = opcode

            self.status = status

        def __str__(self):

            return repr('<opcode: %s, status: %s>'

                        % (self.opcode, self.status))

    class InvalidActionError(Exception):

        def __init__(self, action):

            self._action = action

        def __str__(self):

            return repr(str(self._action))

    name = models.CharField('Network Name', max_length=128)