Synnefo

clientkey = 'astakos'

def qh_add_quota(serial, quotalimits_list):

    if not QUOTAHOLDER_URL:

        return ()

    context = {}

    c = get_client()

    result = c.add_quota(context=context,

                         clientkey=clientkey,

                         serial=serial,

                         add_quota=data)

    return result

def qh_query_serials(serials):

    if not QUOTAHOLDER_URL:

        return ()

    context = {}

    c = get_client()

    result = c.query_serials(context=context,

                             clientkey=clientkey,

                             serials=serials)

    return result

def qh_ack_serials(serials):

    if not QUOTAHOLDER_URL:

        return ()

    context = {}

    c = get_client()

    result = c.ack_serials(context=context,

                           clientkey=clientkey,

                           serials=serials)

    return

# Copyright 2012 GRNET S.A. All rights reserved.

#

# Redistribution and use in source and binary forms, with or without

# modification, are permitted provided that the following conditions

# are met:

#

#   1. Redistributions of source code must retain the above copyright

#      notice, this list of conditions and the following disclaimer.

#

#  2. Redistributions in binary form must reproduce the above copyright

#     notice, this list of conditions and the following disclaimer in the

#     documentation and/or other materials provided with the distribution.

#

# THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND

# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

# ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE

# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

# SUCH DAMAGE.

#

# The views and conclusions contained in the software and documentation are

# those of the authors and should not be interpreted as representing official

# policies, either expressed or implied, of GRNET S.A.

from django.db import connections

from django.db.models import Manager

from django.db.models.query import QuerySet

class ForUpdateManager(Manager):

    """ Model manager implementing SELECT .. FOR UPDATE statement

        This manager implements select_for_update() method in order to use

        row-level locking in the database and guarantee exclusive access, since

        this method is only implemented in Django>=1.4.

        Non-blocking reads are not implemented, and each query including a row

        that is locked by another transaction will block until the lock is

        released. Also care must be taken in order to avoid deadlocks or retry

        transactions that abort due to deadlocks.

        Example:

            networks = Network.objects.select_for_update().filter(public=True)

    """

    def __init__(self, *args, **kwargs):

        super(ForUpdateManager, self).__init__(*args, **kwargs)

        self._select_for_update = False

    def filter(self, *args, **kwargs):

        query = self.get_query_set().filter(*args, **kwargs)

        if self._select_for_update:

            self._select_for_update = False

            return for_update(query)

        else:

            return query

    def get(self, *args, **kwargs):

        if not self._select_for_update:

            return self.get_query_set().get(*args, **kwargs)

        query = self.filter(*args, **kwargs)

        query = list(query)

        num = len(query)

        if num == 1:

            return query[0]

        if not num:

            raise self.model.DoesNotExist(

                    "%s matching query does not exist. "

                    "Lookup parameters were %s" %

                    (self.model._meta.object_name, kwargs))

        raise self.model.MultipleObjectsReturned(

            "get() returned more than one %s -- it returned %s! "

            "Lookup parameters were %s" %

            (self.model._meta.object_name, num, kwargs))

    def select_for_update(self, *args, **kwargs):

        self._select_for_update = True

        return self

def for_update(query):

    """ Rewrite query using SELECT .. FOR UPDATE.

    """

    if 'sqlite' in connections[query.db].settings_dict['ENGINE'].lower():

        # SQLite  does not support FOR UPDATE

        return query

    sql, params = query.query.get_compiler(query.db).as_sql()

    return query.model._default_manager.raw(sql.rstrip() + ' FOR UPDATE',

                                            params)

class ProtectedDeleteManager(ForUpdateManager):

    """ Manager for protecting Backend deletion.

        Call Backend delete() method in order to prevent deletion

        of Backends that host non-deleted VirtualMachines.

    """

    def get_query_set(self):

        return BackendQuerySet(self.model, using=self._db)

class BackendQuerySet(QuerySet):

    def delete(self):

        for backend in self._clone():

            backend.delete()

    register_users, send_quota, register_resources, qh_add_quota, QuotaLimits,

    qh_query_serials, qh_ack_serials)

from .managers import ForUpdateManager

            grants = p.application.projectresourcegrant_set.all()

        project.application = self

        # This will block while syncing,

        # but unblock before setting the membership state.

        # See ProjectMembership.set_sync()

        project.set_membership_pending_sync()

    application                 =   models.OneToOneField(

                                            related_name='project')

        application = self.application

        ACCEPTED = ProjectMembership.ACCEPTED

        PENDING  = ProjectMembership.PENDING

            Q(state=ACCEPTED) | Q(state=PENDING))

    def set_membership_pending_sync(self):

        ACCEPTED = ProjectMembership.ACCEPTED

        PENDING  = ProjectMembership.PENDING

        sfu = self.projectmembership_set.select_for_update()

        members = sfu.filter(Q(state=ACCEPTED) | Q(state=PENDING))

            member.state = member.PENDING

    objects     =   ForUpdateManager()

        self.state = self.REQUESTED

        trigger_sync()

        self._set_history_item(reason='REMOVE')

        trigger_sync()

                capacity += new_grant.member_capacity

                import_limit += new_grant.member_import_limit

                export_limit += new_grant.member_export_limit

    def set_sync(self):

        state = self.state

        if state == self.PENDING:

            pending_application = self.pending_application

            if pending_application is None:

                m = _("%s: attempt to sync an empty pending application") % (

                    self, state)

                raise AssertionError(m)

            self.application = pending_application

            self.pending_application = None

            self.pending_serial = None

            # project.application may have changed in the meantime,

            # in which case we stay PENDING;

            # we are safe to check due to select_for_update

            if self.application == self.project.application:

                self.state = self.ACCEPTED

            self.save()

        elif state == self.REMOVING:

            self.delete()

        else:

            m = _("%s: attempt to sync in state '%s'") % (self, state)

            raise AssertionError(m)

class Serial(models.Model):

    serial  =   models.AutoField(primary_key=True)

def new_serial():

    s = Serial.create()

    return s.serial

    serials_to_ack = set(qh_query_serials([]))

    qh_ack_serials(list(serials_to_ack))

    serial = new_serial()

        membership.pending_application = membership.project.application

    # ProjectApplication.approve() unblocks here

    # and can set PENDING an already PENDING membership

    # which has been scheduled to sync with the old project.application

    # Need to check in ProjectMembership.set_sync()

    qh_add_quota(serial, quotas)