Switch from FLAGS to CONF in nova.scheduler

Use the global CONF variable instead of FLAGS. This is purely a cleanup
since FLAGS is already just another reference to CONF.

We leave the nova.flags imports until a later cleanup commit since
removing them may cause unpredictable problems due to config options not
being registered.

Change-Id: Ia3f66aec300fd88e91cef926da735f9e95aa2cc2

17 files changed, 80 insertions, 68 deletions

diff --git a/nova/scheduler/chance.py b/nova/scheduler/chance.py
index 6d6288d83..1a608da29 100644
--- a/nova/scheduler/chance.py
+++ b/nova/scheduler/chance.py
@@ -23,11 +23,12 @@ Chance (Random) Scheduler implementation
 
 import random
 
+from nova import config
 from nova import exception
 from nova import flags
 from nova.scheduler import driver
 
-FLAGS = flags.FLAGS
+CONF = config.CONF
 
 
 class ChanceScheduler(driver.Scheduler):
@@ -65,7 +66,7 @@ class ChanceScheduler(driver.Scheduler):
         for num, instance_uuid in enumerate(instance_uuids):
             request_spec['instance_properties']['launch_index'] = num
             try:
-                host = self._schedule(context, FLAGS.compute_topic,
+                host = self._schedule(context, CONF.compute_topic,
                                       request_spec, filter_properties)
                 updated_instance = driver.instance_update_db(context,
                         instance_uuid)
@@ -88,7 +89,7 @@ class ChanceScheduler(driver.Scheduler):
                              filter_properties, instance, instance_type,
                              reservations):
         """Select a target for resize."""
-        host = self._schedule(context, FLAGS.compute_topic, request_spec,
+        host = self._schedule(context, CONF.compute_topic, request_spec,
                               filter_properties)
         self.compute_rpcapi.prep_resize(context, image, instance,
                 instance_type, host, reservations)
diff --git a/nova/scheduler/driver.py b/nova/scheduler/driver.py
index 13f0029ee..f93268906 100644
--- a/nova/scheduler/driver.py
+++ b/nova/scheduler/driver.py
@@ -53,8 +53,8 @@ scheduler_driver_opts = [
                help='Maximum number of attempts to schedule an instance'),
     ]
 
-FLAGS = flags.FLAGS
-FLAGS.register_opts(scheduler_driver_opts)
+CONF = config.CONF
+CONF.register_opts(scheduler_driver_opts)
 
 CONF = config.CONF
 CONF.import_opt('instances_path', 'nova.compute.manager')
@@ -107,7 +107,7 @@ def cast_to_compute_host(context, host, method, **kwargs):
         instance_update_db(context, instance_uuid)
 
     rpc.cast(context,
-             rpc.queue_get_for(context, FLAGS.compute_topic, host),
+             rpc.queue_get_for(context, CONF.compute_topic, host),
              {"method": method, "args": kwargs})
     LOG.debug(_("Casted '%(method)s' to compute '%(host)s'") % locals())
 
@@ -115,7 +115,7 @@ def cast_to_compute_host(context, host, method, **kwargs):
 def cast_to_host(context, topic, host, method, **kwargs):
     """Generic cast to host"""
 
-    topic_mapping = {FLAGS.compute_topic: cast_to_compute_host}
+    topic_mapping = {CONF.compute_topic: cast_to_compute_host}
 
     func = topic_mapping.get(topic)
     if func:
@@ -151,7 +151,7 @@ class Scheduler(object):
 
     def __init__(self):
         self.host_manager = importutils.import_object(
-                FLAGS.scheduler_host_manager)
+                CONF.scheduler_host_manager)
         self.compute_api = compute_api.API()
         self.compute_rpcapi = compute_rpcapi.ComputeAPI()
 
diff --git a/nova/scheduler/filter_scheduler.py b/nova/scheduler/filter_scheduler.py
index 78bd49a96..c43e48876 100644
--- a/nova/scheduler/filter_scheduler.py
+++ b/nova/scheduler/filter_scheduler.py
@@ -21,6 +21,7 @@ Weighing Functions.
 
 import operator
 
+from nova import config
 from nova import exception
 from nova import flags
 from nova.openstack.common import importutils
@@ -30,8 +31,7 @@ from nova.scheduler import driver
 from nova.scheduler import least_cost
 from nova.scheduler import scheduler_options
 
-
-FLAGS = flags.FLAGS
+CONF = config.CONF
 LOG = logging.getLogger(__name__)
 
 
@@ -61,7 +61,7 @@ class FilterScheduler(driver.Scheduler):
         notifier.notify(context, notifier.publisher_id("scheduler"),
                         'scheduler.run_instance.start', notifier.INFO, payload)
 
-        weighted_hosts = self._schedule(context, FLAGS.compute_topic,
+        weighted_hosts = self._schedule(context, CONF.compute_topic,
                                         request_spec, filter_properties,
                                         instance_uuids)
 
@@ -108,7 +108,7 @@ class FilterScheduler(driver.Scheduler):
         the prep_resize operation to it.
         """
 
-        hosts = self._schedule(context, FLAGS.compute_topic, request_spec,
+        hosts = self._schedule(context, CONF.compute_topic, request_spec,
                                filter_properties, [instance['uuid']])
         if not hosts:
             raise exception.NoValidHost(reason="")
@@ -187,7 +187,7 @@ class FilterScheduler(driver.Scheduler):
         filter_properties['os_type'] = os_type
 
     def _max_attempts(self):
-        max_attempts = FLAGS.scheduler_max_attempts
+        max_attempts = CONF.scheduler_max_attempts
         if max_attempts < 1:
             raise exception.NovaException(_("Invalid value for "
                 "'scheduler_max_attempts', must be >= 1"))
@@ -226,7 +226,7 @@ class FilterScheduler(driver.Scheduler):
         ordered by their fitness.
         """
         elevated = context.elevated()
-        if topic != FLAGS.compute_topic:
+        if topic != CONF.compute_topic:
             msg = _("Scheduler only understands Compute nodes (for now)")
             raise NotImplementedError(msg)
 
@@ -306,12 +306,12 @@ class FilterScheduler(driver.Scheduler):
         """
         if topic is None:
             # Schedulers only support compute right now.
-            topic = FLAGS.compute_topic
+            topic = CONF.compute_topic
         if topic in self.cost_function_cache:
             return self.cost_function_cache[topic]
 
         cost_fns = []
-        for cost_fn_str in FLAGS.least_cost_functions:
+        for cost_fn_str in CONF.least_cost_functions:
             if '.' in cost_fn_str:
                 short_name = cost_fn_str.split('.')[-1]
             else:
@@ -333,7 +333,7 @@ class FilterScheduler(driver.Scheduler):
 
             try:
                 flag_name = "%s_weight" % cost_fn.__name__
-                weight = getattr(FLAGS, flag_name)
+                weight = getattr(CONF, flag_name)
             except AttributeError:
                 raise exception.SchedulerWeightFlagNotFound(
                         flag_name=flag_name)
diff --git a/nova/scheduler/filters/compute_filter.py b/nova/scheduler/filters/compute_filter.py
index 4af71c7b4..202f8232a 100644
--- a/nova/scheduler/filters/compute_filter.py
+++ b/nova/scheduler/filters/compute_filter.py
@@ -13,12 +13,13 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from nova import config
 from nova import flags
 from nova.openstack.common import log as logging
 from nova.scheduler import filters
 from nova import utils
 
-FLAGS = flags.FLAGS
+CONF = config.CONF
 
 LOG = logging.getLogger(__name__)
 
@@ -29,7 +30,7 @@ class ComputeFilter(filters.BaseHostFilter):
     def host_passes(self, host_state, filter_properties):
         """Returns True for only active compute nodes"""
         instance_type = filter_properties.get('instance_type')
-        if host_state.topic != FLAGS.compute_topic or not instance_type:
+        if host_state.topic != CONF.compute_topic or not instance_type:
             return True
         capabilities = host_state.capabilities
         service = host_state.service
diff --git a/nova/scheduler/filters/core_filter.py b/nova/scheduler/filters/core_filter.py
index 0c4a67dcc..9c93df930 100644
--- a/nova/scheduler/filters/core_filter.py
+++ b/nova/scheduler/filters/core_filter.py
@@ -15,6 +15,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import log as logging
@@ -27,8 +28,8 @@ cpu_allocation_ratio_opt = cfg.FloatOpt('cpu_allocation_ratio',
         default=16.0,
         help='Virtual CPU to Physical CPU allocation ratio')
 
-FLAGS = flags.FLAGS
-FLAGS.register_opt(cpu_allocation_ratio_opt)
+CONF = config.CONF
+CONF.register_opt(cpu_allocation_ratio_opt)
 
 
 class CoreFilter(filters.BaseHostFilter):
@@ -37,7 +38,7 @@ class CoreFilter(filters.BaseHostFilter):
     def host_passes(self, host_state, filter_properties):
         """Return True if host has sufficient CPU cores."""
         instance_type = filter_properties.get('instance_type')
-        if host_state.topic != FLAGS.compute_topic or not instance_type:
+        if host_state.topic != CONF.compute_topic or not instance_type:
             return True
 
         if not host_state.vcpus_total:
@@ -46,7 +47,7 @@ class CoreFilter(filters.BaseHostFilter):
             return True
 
         instance_vcpus = instance_type['vcpus']
-        vcpus_total = host_state.vcpus_total * FLAGS.cpu_allocation_ratio
+        vcpus_total = host_state.vcpus_total * CONF.cpu_allocation_ratio
 
         # Only provide a VCPU limit to compute if the virt driver is reporting
         # an accurate count of installed VCPUs. (XenServer driver does not)
diff --git a/nova/scheduler/filters/disk_filter.py b/nova/scheduler/filters/disk_filter.py
index 88b8c3377..358583b8a 100644
--- a/nova/scheduler/filters/disk_filter.py
+++ b/nova/scheduler/filters/disk_filter.py
@@ -13,6 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import log as logging
@@ -23,8 +24,8 @@ LOG = logging.getLogger(__name__)
 disk_allocation_ratio_opt = cfg.FloatOpt("disk_allocation_ratio", default=1.0,
                          help="virtual disk to physical disk allocation ratio")
 
-FLAGS = flags.FLAGS
-FLAGS.register_opt(disk_allocation_ratio_opt)
+CONF = config.CONF
+CONF.register_opt(disk_allocation_ratio_opt)
 
 
 class DiskFilter(filters.BaseHostFilter):
@@ -39,7 +40,7 @@ class DiskFilter(filters.BaseHostFilter):
         free_disk_mb = host_state.free_disk_mb
         total_usable_disk_mb = host_state.total_usable_disk_gb * 1024
 
-        disk_mb_limit = total_usable_disk_mb * FLAGS.disk_allocation_ratio
+        disk_mb_limit = total_usable_disk_mb * CONF.disk_allocation_ratio
         used_disk_mb = total_usable_disk_mb - free_disk_mb
         usable_disk_mb = disk_mb_limit - used_disk_mb
 
diff --git a/nova/scheduler/filters/io_ops_filter.py b/nova/scheduler/filters/io_ops_filter.py
index c2e0205a3..1b40bae62 100644
--- a/nova/scheduler/filters/io_ops_filter.py
+++ b/nova/scheduler/filters/io_ops_filter.py
@@ -13,6 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import log as logging
@@ -24,8 +25,8 @@ max_io_ops_per_host_opt = cfg.IntOpt("max_io_ops_per_host",
         default=8,
         help="Ignore hosts that have too many builds/resizes/snaps/migrations")
 
-FLAGS = flags.FLAGS
-FLAGS.register_opt(max_io_ops_per_host_opt)
+CONF = config.CONF
+CONF.register_opt(max_io_ops_per_host_opt)
 
 
 class IoOpsFilter(filters.BaseHostFilter):
@@ -36,7 +37,7 @@ class IoOpsFilter(filters.BaseHostFilter):
         compute node statistics to decide whether to filter.
         """
         num_io_ops = host_state.num_io_ops
-        max_io_ops = FLAGS.max_io_ops_per_host
+        max_io_ops = CONF.max_io_ops_per_host
         passes = num_io_ops < max_io_ops
         if not passes:
             LOG.debug(_("%(host_state)s fails I/O ops check: Max IOs per host "
diff --git a/nova/scheduler/filters/isolated_hosts_filter.py b/nova/scheduler/filters/isolated_hosts_filter.py
index 0d67b7b80..d1d16b80b 100644
--- a/nova/scheduler/filters/isolated_hosts_filter.py
+++ b/nova/scheduler/filters/isolated_hosts_filter.py
@@ -13,12 +13,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-
+from nova import config
 from nova import flags
 from nova.scheduler import filters
 
-
-FLAGS = flags.FLAGS
+CONF = config.CONF
 
 
 class IsolatedHostsFilter(filters.BaseHostFilter):
@@ -28,6 +27,6 @@ class IsolatedHostsFilter(filters.BaseHostFilter):
         spec = filter_properties.get('request_spec', {})
         props = spec.get('instance_properties', {})
         image_ref = props.get('image_ref')
-        image_isolated = image_ref in FLAGS.isolated_images
-        host_isolated = host_state.host in FLAGS.isolated_hosts
+        image_isolated = image_ref in CONF.isolated_images
+        host_isolated = host_state.host in CONF.isolated_hosts
         return image_isolated == host_isolated
diff --git a/nova/scheduler/filters/num_instances_filter.py b/nova/scheduler/filters/num_instances_filter.py
index e96539c0c..17c7ebc22 100644
--- a/nova/scheduler/filters/num_instances_filter.py
+++ b/nova/scheduler/filters/num_instances_filter.py
@@ -13,6 +13,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import log as logging
@@ -24,8 +25,8 @@ max_instances_per_host_opt = cfg.IntOpt("max_instances_per_host",
         default=50,
         help="Ignore hosts that have too many instances")
 
-FLAGS = flags.FLAGS
-FLAGS.register_opt(max_instances_per_host_opt)
+CONF = config.CONF
+CONF.register_opt(max_instances_per_host_opt)
 
 
 class NumInstancesFilter(filters.BaseHostFilter):
@@ -33,7 +34,7 @@ class NumInstancesFilter(filters.BaseHostFilter):
 
     def host_passes(self, host_state, filter_properties):
         num_instances = host_state.num_instances
-        max_instances = FLAGS.max_instances_per_host
+        max_instances = CONF.max_instances_per_host
         passes = num_instances < max_instances
         if not passes:
             LOG.debug(_("%(host_state)s fails num_instances check: Max "
diff --git a/nova/scheduler/filters/ram_filter.py b/nova/scheduler/filters/ram_filter.py
index 22ba0252c..85370dc2c 100644
--- a/nova/scheduler/filters/ram_filter.py
+++ b/nova/scheduler/filters/ram_filter.py
@@ -14,6 +14,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import log as logging
@@ -25,8 +26,8 @@ ram_allocation_ratio_opt = cfg.FloatOpt("ram_allocation_ratio",
         default=1.5,
         help="virtual ram to physical ram allocation ratio")
 
-FLAGS = flags.FLAGS
-FLAGS.register_opt(ram_allocation_ratio_opt)
+CONF = config.CONF
+CONF.register_opt(ram_allocation_ratio_opt)
 
 
 class RamFilter(filters.BaseHostFilter):
@@ -39,7 +40,7 @@ class RamFilter(filters.BaseHostFilter):
         free_ram_mb = host_state.free_ram_mb
         total_usable_ram_mb = host_state.total_usable_ram_mb
 
-        memory_mb_limit = total_usable_ram_mb * FLAGS.ram_allocation_ratio
+        memory_mb_limit = total_usable_ram_mb * CONF.ram_allocation_ratio
         used_ram_mb = total_usable_ram_mb - free_ram_mb
         usable_ram = memory_mb_limit - used_ram_mb
         if not usable_ram >= requested_ram:
diff --git a/nova/scheduler/filters/trusted_filter.py b/nova/scheduler/filters/trusted_filter.py
index 69968a766..4fd0488d9 100644
--- a/nova/scheduler/filters/trusted_filter.py
+++ b/nova/scheduler/filters/trusted_filter.py
@@ -48,6 +48,7 @@ import httplib
 import socket
 import ssl
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import jsonutils
@@ -81,10 +82,10 @@ trusted_opts = [
                help='attestation authorization blob - must change'),
 ]
 
-FLAGS = flags.FLAGS
+CONF = config.CONF
 trust_group = cfg.OptGroup(name='trusted_computing', title='Trust parameters')
-FLAGS.register_group(trust_group)
-FLAGS.register_opts(trusted_opts, group='trusted_computing')
+CONF.register_group(trust_group)
+CONF.register_opts(trusted_opts, group=trust_group)
 
 
 class HTTPSClientAuthConnection(httplib.HTTPSConnection):
@@ -124,13 +125,13 @@ class AttestationService(httplib.HTTPSConnection):
     # Provide access wrapper to attestation server to get integrity report.
 
     def __init__(self):
-        self.api_url = FLAGS.trusted_computing.attestation_api_url
-        self.host = FLAGS.trusted_computing.attestation_server
-        self.port = FLAGS.trusted_computing.attestation_port
-        self.auth_blob = FLAGS.trusted_computing.attestation_auth_blob
+        self.api_url = CONF.trusted_computing.attestation_api_url
+        self.host = CONF.trusted_computing.attestation_server
+        self.port = CONF.trusted_computing.attestation_port
+        self.auth_blob = CONF.trusted_computing.attestation_auth_blob
         self.key_file = None
         self.cert_file = None
-        self.ca_file = FLAGS.trusted_computing.attestation_server_ca_file
+        self.ca_file = CONF.trusted_computing.attestation_server_ca_file
         self.request_count = 100
 
     def _do_request(self, method, action_url, body, headers):
diff --git a/nova/scheduler/host_manager.py b/nova/scheduler/host_manager.py
index fc9f3c8cc..91e16ad34 100644
--- a/nova/scheduler/host_manager.py
+++ b/nova/scheduler/host_manager.py
@@ -21,6 +21,7 @@ import UserDict
 
 from nova.compute import task_states
 from nova.compute import vm_states
+from nova import config
 from nova import db
 from nova import exception
 from nova import flags
@@ -49,8 +50,8 @@ host_manager_opts = [
                       'when not specified in the request.'),
     ]
 
-FLAGS = flags.FLAGS
-FLAGS.register_opts(host_manager_opts)
+CONF = config.CONF
+CONF.register_opts(host_manager_opts)
 
 LOG = logging.getLogger(__name__)
 
@@ -281,7 +282,7 @@ class HostManager(object):
         self.service_states = {}  # { <host> : { <service> : { cap k : v }}}
         self.host_state_map = {}
         self.filter_classes = filters.get_filter_classes(
-                FLAGS.scheduler_available_filters)
+                CONF.scheduler_available_filters)
 
     def _choose_host_filters(self, filters):
         """Since the caller may specify which filters to use we need
@@ -290,7 +291,7 @@ class HostManager(object):
         of acceptable filters.
         """
         if filters is None:
-            filters = FLAGS.scheduler_default_filters
+            filters = CONF.scheduler_default_filters
         if not isinstance(filters, (list, tuple)):
             filters = [filters]
         good_filters = []
@@ -347,7 +348,7 @@ class HostManager(object):
         with the instance (in case the InstanceType changed since the
         instance was created)."""
 
-        if topic != FLAGS.compute_topic:
+        if topic != CONF.compute_topic:
             raise NotImplementedError(_(
                 "host_manager only implemented for 'compute'"))
 
diff --git a/nova/scheduler/least_cost.py b/nova/scheduler/least_cost.py
index bccdd0a4f..d3eaee735 100644
--- a/nova/scheduler/least_cost.py
+++ b/nova/scheduler/least_cost.py
@@ -22,6 +22,7 @@ The cost-function and weights are tabulated, and the host with the least cost
 is then selected for provisioning.
 """
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import log as logging
@@ -45,8 +46,8 @@ least_cost_opts = [
                     'e.g. spread-first'),
     ]
 
-FLAGS = flags.FLAGS
-FLAGS.register_opts(least_cost_opts)
+CONF = config.CONF
+CONF.register_opts(least_cost_opts)
 
 # TODO(sirp): Once we have enough of these rules, we can break them out into a
 # cost_functions.py file (perhaps in a least_cost_scheduler directory)
diff --git a/nova/scheduler/manager.py b/nova/scheduler/manager.py
index 531c54726..77f5a0259 100644
--- a/nova/scheduler/manager.py
+++ b/nova/scheduler/manager.py
@@ -26,6 +26,7 @@ import sys
 from nova.compute import rpcapi as compute_rpcapi
 from nova.compute import utils as compute_utils
 from nova.compute import vm_states
+from nova import config
 import nova.context
 from nova import db
 from nova import exception
@@ -46,8 +47,8 @@ scheduler_driver_opt = cfg.StrOpt('scheduler_driver',
         default='nova.scheduler.filter_scheduler.FilterScheduler',
         help='Default driver to use for the scheduler')
 
-FLAGS = flags.FLAGS
-FLAGS.register_opt(scheduler_driver_opt)
+CONF = config.CONF
+CONF.register_opt(scheduler_driver_opt)
 
 QUOTAS = quota.QUOTAS
 
@@ -59,7 +60,7 @@ class SchedulerManager(manager.Manager):
 
     def __init__(self, scheduler_driver=None, *args, **kwargs):
         if not scheduler_driver:
-            scheduler_driver = FLAGS.scheduler_driver
+            scheduler_driver = CONF.scheduler_driver
         self.driver = importutils.import_object(scheduler_driver)
         super(SchedulerManager, self).__init__(*args, **kwargs)
 
diff --git a/nova/scheduler/multi.py b/nova/scheduler/multi.py
index 13e3c0e1a..7c68bb12a 100644
--- a/nova/scheduler/multi.py
+++ b/nova/scheduler/multi.py
@@ -27,6 +27,7 @@ schedule requests to compute nodes but provide their own manager and topic.
 https://bugs.launchpad.net/nova/+bug/1009681
 """
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import importutils
@@ -43,8 +44,8 @@ multi_scheduler_opts = [
                help='Default driver to use for scheduling calls'),
     ]
 
-FLAGS = flags.FLAGS
-FLAGS.register_opts(multi_scheduler_opts)
+CONF = config.CONF
+CONF.register_opts(multi_scheduler_opts)
 
 
 class MultiScheduler(driver.Scheduler):
@@ -58,9 +59,9 @@ class MultiScheduler(driver.Scheduler):
     def __init__(self):
         super(MultiScheduler, self).__init__()
         compute_driver = importutils.import_object(
-                FLAGS.compute_scheduler_driver)
+                CONF.compute_scheduler_driver)
         default_driver = importutils.import_object(
-                FLAGS.default_scheduler_driver)
+                CONF.default_scheduler_driver)
 
         self.drivers = {'compute': compute_driver,
                         'default': default_driver}
diff --git a/nova/scheduler/rpcapi.py b/nova/scheduler/rpcapi.py
index b41668733..cbb6712db 100644
--- a/nova/scheduler/rpcapi.py
+++ b/nova/scheduler/rpcapi.py
@@ -18,12 +18,12 @@
 Client side of the scheduler manager RPC API.
 """
 
+from nova import config
 from nova import flags
 from nova.openstack.common import jsonutils
 import nova.openstack.common.rpc.proxy
 
-
-FLAGS = flags.FLAGS
+CONF = config.CONF
 
 
 class SchedulerAPI(nova.openstack.common.rpc.proxy.RpcProxy):
@@ -60,7 +60,7 @@ class SchedulerAPI(nova.openstack.common.rpc.proxy.RpcProxy):
     BASE_RPC_API_VERSION = '2.0'
 
     def __init__(self):
-        super(SchedulerAPI, self).__init__(topic=FLAGS.scheduler_topic,
+        super(SchedulerAPI, self).__init__(topic=CONF.scheduler_topic,
                 default_version=self.BASE_RPC_API_VERSION)
 
     def run_instance(self, ctxt, request_spec, admin_password,
diff --git a/nova/scheduler/scheduler_options.py b/nova/scheduler/scheduler_options.py
index 7acf2f750..e8be0070b 100644
--- a/nova/scheduler/scheduler_options.py
+++ b/nova/scheduler/scheduler_options.py
@@ -26,6 +26,7 @@ import datetime
 import json
 import os
 
+from nova import config
 from nova import flags
 from nova.openstack.common import cfg
 from nova.openstack.common import log as logging
@@ -37,8 +38,8 @@ scheduler_json_config_location_opt = cfg.StrOpt(
         default='',
         help='Absolute path to scheduler configuration JSON file.')
 
-FLAGS = flags.FLAGS
-FLAGS.register_opt(scheduler_json_config_location_opt)
+CONF = config.CONF
+CONF.register_opt(scheduler_json_config_location_opt)
 
 LOG = logging.getLogger(__name__)
 
@@ -86,7 +87,7 @@ class SchedulerOptions(object):
     def get_configuration(self, filename=None):
         """Check the json file for changes and load it if needed."""
         if not filename:
-            filename = FLAGS.scheduler_json_config_location
+            filename = CONF.scheduler_json_config_location
         if not filename:
             return self.data
         if self.last_checked: