Synnefo

from commissioning import Controller

from django.db.models import Model, BigIntegerField, CharField, IntegerField

from django.db import transaction

from json import dumps as json_dumps, loads as json_loads

class ControllerCommission(Model):

    serial = BigIntegerField(primary_key=True)

    clientkey = CharField(null=False, max_length=72)

    physical_description = CharField(null=False, max_length=4096)

    status = IntegerField(null=False)

class DjangoController(Controller):

    def get_commission_issue(self, commission_spec):

        """Prepare and return the arguments for the

           quotaholder's issue_commission call,

           containing the provisions required and

           the target entity for their allocation.

        """

        raise NotImplementedError

    def register_commission(self,   serial,

                                    clientkey,

                                    physical_description    ):

        """Register a commission to the controller's stable storage,

           along with the quotaholder serial and clientkey,

           and the target physical description.

           This information is needed to co-ordinate the commission

           execution among the quotaholder server, the controller,

           and the physical layer implementing the resource.

        """

        physical_description = json_dumps(physical_description)

        create = ControllerCommission.objects.create

        create( serial=serial, clientkey=clientkey,

                physical_description=physical_description )

    def get_commission(self, serial):

        """Retrieve the commission registered with serial"""

        try:

            commission = ControllerCommission.objects.get(serial=serial)

        except ControllerCommission.DoesNotExist:

            return None

        return (commission.serial,

                commission.clientkey,

                commission.physical_description,

                commission.status)

    def complete_commission(self, serial):

        """Mark and commit in stable storage the commission identified by

           a serial as to-be-completed-successfully,

           i.e that it has succeeded in producing a physical resource

           and is to be removed from being tracked by the holder server,

           controller, and physical layers.

        """

        commission = ControllerCommission.objects.get(serial=serial)

        commission.status = 1

        commission.save()

    def is_commission_complete(self, serial):

        """Return true if the serial is marked as

           completed by complete_commission()

        """

        commission = ControllerCommission.objects.get(serial=serial)

        return commission.status > 0

    def fail_commission(self, serial):

        """Mark and commit in stable storage the commission identified by

           a serial as to-be-completed-unsuccessfully,

           i.e. that it has failed in producing a physical resource

           and is to be removed from being tracked by the holder server,

           controller, and physical layers.

        """

        commission = ControllerCommission.objects.get(serial=serial)

        commission.status = -1

        commission.save()

    def is_commission_failing(self, serial):

        """Return true if the serial is marked as

           failing by fail_commission()

        """

        commission = ControllerCommission.objects.get(serial=serial)

        return commission.status < 0

    def retire_commission(self, serial):

        """Stop tracking the commission identified by a serial"""

        try:

            commission = ControllerCommission.objects.get(serial=serial)

        except ControllerCommission.DoesNotExist:

            return

        commission.delete()