# OS-Ken API Reference

class os_ken.base.app_manager.OSKenApp(*_args, **_kwargs)

  The base class for OSKen applications.

  OSKenApp subclasses are instantiated after osken-manager loaded all requested OSKen application modules. __init__ should call OSKenApp.__init__ with the same arguments. It's illegal to send any events in __init__.

  The instance attribute 'name' is the name of the class used for message routing among OSKen applications. (Cf. send_event) It's set to __class__.__name__ by OSKenApp.__init__. It's discouraged for subclasses to override this.

  OFP_VERSIONS = None

    A list of supported OpenFlow versions for this OSKenApp. The default is all versions supported by the framework.

    Examples:

        OFP_VERSIONS = [ofproto_v1_0.OFP_VERSION,
                        ofproto_v1_2.OFP_VERSION]

    If multiple OSKen applications are loaded in the system, the intersection of their OFP_VERSIONS is used.

  _CONTEXTS = {}

    A dictionary to specify contexts which this OSKen application wants to use. Its key is a name of context and its value is an ordinary class which implements the context. The class is instantiated by app_manager and the instance is shared among OSKenApp subclasses which has _CONTEXTS member with the same key. A OSKenApp subclass can obtain a reference to the instance via its __init__'s kwargs as the following.

    Example:

        _CONTEXTS = {
            'network': network.Network
        }

        def __init__(self, *args, *kwargs):
            self.network = kwargs['network']

  _EVENTS = []

    A list of event classes which this OSKenApp subclass would generate. This should be specified if and only if event classes are defined in a different python module from the OSKenApp subclass is.

  close()

    teardown method. The method name, close, is chosen for python context manager

  classmethod context_iteritems()

    Return iterator over the (key, contxt class) of application context

  reply_to_request(req, rep)

    Send a reply for a synchronous request sent by send_request. The first argument should be an instance of EventRequestBase. The second argument should be an instance of EventReplyBase.

  send_event(name, ev, state=None)

    Send the specified event to the OSKenApp instance specified by name.

  send_event_to_observers(ev, state=None)

    Send the specified event to all observers of this OSKenApp.

  send_request(req)

    Make a synchronous request. Set req.sync to True, send it to a OSKen application specified by req.dst, and block until receiving a reply. Returns the received reply. The argument should be an instance of EventRequestBase.

  start()

    Hook that is called after startup initialization is done.

class os_ken.controller.dpset.DPSet(*args, **kwargs)

  DPSet application manages a set of switches (datapaths) connected to this controller.

  Usage Example:

      # ...(snip)...
      from os_ken.controller import dpset

      class MyApp(app_manager.OSKenApp):
          _CONTEXTS = {
              'dpset': dpset.DPSet,
          }

          def __init__(self, *args, **kwargs):
              super(MyApp, self).__init__(*args, **kwargs)
              # Stores DPSet instance to call its API in this app
              self.dpset = kwargs['dpset']

          def _my_handler(self):
              # Get the datapath object which has the given dpid
              dpid = 1
              dp = self.dpset.get(dpid)
              if dp is None:
                  self.logger.info('No such datapath: dpid=%d', dpid)

  get(dp_id)

    This method returns the os_ken.controller.controller.Datapath instance for the given Datapath ID.

  get_all()

    This method returns a list of tuples which represents instances for switches connected to this controller. The tuple consists of a Datapath ID and an instance of os_ken.controller.controller.Datapath.

    A return value looks like the following:

        [ (dpid_A, Datapath_A), (dpid_B, Datapath_B), ... ]

  get_port(dpid, port_no)

    This method returns the os_ken.controller.dpset.PortState instance for the given Datapath ID and the port number. Raises os_ken_exc.PortNotFound if no such a datapath connected to this controller or no such a port exists.

  get_ports(dpid)

    This method returns a list of os_ken.controller.dpset.PortState instances for the given Datapath ID. Raises KeyError if no such a datapath connected to this controller.

this page last updated: 2026-04-10 03:11:34

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