From 873ebc36b127c922b294c885ecba5c678b8dc629 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Tue, 15 Feb 2011 11:15:59 -0800
Subject: [PATCH 02/14] zone/info works

---
 bin/nova-combined | 4 ++--
 nova/flags.py     | 5 +++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/bin/nova-combined b/bin/nova-combined
index 913c866b..a0f552d6 100755
--- a/bin/nova-combined
+++ b/bin/nova-combined
@@ -53,11 +53,11 @@ if __name__ == '__main__':
 
     compute = service.Service.create(binary='nova-compute')
     network = service.Service.create(binary='nova-network')
-    volume = service.Service.create(binary='nova-volume')
+    #volume = service.Service.create(binary='nova-volume')
     scheduler = service.Service.create(binary='nova-scheduler')
     #objectstore = service.Service.create(binary='nova-objectstore')
 
-    service.serve(compute, network, volume, scheduler)
+    service.serve(compute, network, scheduler)
 
     apps = []
     paste_config_file = wsgi.paste_config_file('nova-api.conf')
diff --git a/nova/flags.py b/nova/flags.py
index 3ba3fe6f..0a45499f 100644
--- a/nova/flags.py
+++ b/nova/flags.py
@@ -312,3 +312,8 @@ DEFINE_string('host', socket.gethostname(),
 
 DEFINE_string('node_availability_zone', 'nova',
               'availability zone of this node')
+
+DEFINE_string('zone_name', 'nova', 'name of this zone')
+DEFINE_string('zone_capabilities', 'xen, linux', 
+              'comma-delimited list of tags which represent boolean'
+              ' capabilities of this zone')

From 05bfa83249b603fbb8896916adb2bc474fd33d42 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Wed, 16 Feb 2011 11:05:03 -0800
Subject: [PATCH 03/14] novatools call to child zones done

---
 nova/scheduler/zone_manager.py | 126 +++++++++++++++++++++++++++++++++
 1 file changed, 126 insertions(+)
 create mode 100644 nova/scheduler/zone_manager.py

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
new file mode 100644
index 00000000..dd910eb0
--- /dev/null
+++ b/nova/scheduler/zone_manager.py
@@ -0,0 +1,126 @@
+# Copyright (c) 2010 Openstack, LLC.
+# Copyright 2010 United States Government as represented by the
+# Administrator of the National Aeronautics and Space Administration.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+ZoneManager oversees all communications with child Zones.
+"""
+
+import novatools
+import thread
+
+from datetime import datetime
+from eventlet.greenpool import GreenPool
+
+from nova import db
+from nova import flags
+from nova import log as logging
+
+FLAGS = flags.FLAGS
+flags.DEFINE_integer('zone_db_check_interval', 60,
+                    'Seconds between getting fresh zone info from db.')
+flags.DEFINE_integer('zone_failures_to_offline', 3,
+             'Number of consecutive errors before marking zone offline')
+
+
+class ZoneState(object):
+    """Holds the state of all connected child zones."""
+    def __init__(self):
+        self.is_active = True
+        self.name = None
+        self.capabilities = None
+        self.attempt = 0
+        self.last_seen = datetime.min
+        self.last_exception = None
+        self.last_exception_time = None
+ 
+    def update_credentials(self, zone):
+        """Update zone credentials from db"""
+        self.zone_id = zone.id
+        self.api_url = zone.api_url
+        self.username = zone.username
+        self.password = zone.password
+ 
+    def update_metadata(self, zone_metadata):
+        """Update zone metadata after successful communications with
+           child zone."""
+        self.last_seen = datetime.now()
+        self.attempt = 0
+        self.name = zone_metadata["name"]
+        self.capabilities = zone_metadata["capabilities"]
+        self.is_active = True
+
+    def log_error(self, exception):
+        """Something went wrong. Check to see if zone should be
+           marked as offline."""
+        self.last_exception = exception
+        self.last_exception_time = datetime.now()
+        logging.warning(_("%s error talking to zone %s") % (exception,
+            zone.api_url, FLAGS.zone_failures_to_offline))
+
+       self.attempt += 1
+        if self.attempt >= FLAGS.zone_failures_to_offline:
+           self.is_active = False
+           logging.error(_("No answer from zone %s after %d "
+               "attempts. Marking inactive.") % (zone.api_url,
+               FLAGS.zone_failures_to_offline))
+
+def _poll_zone(zone):
+    """Eventlet worker to poll a zone."""
+    logging.debug("_POLL_ZONE: STARTING")
+    os = novatools.OpenStack(zone.username, zone.password, zone.api_url)
+    try:
+        zone.update_metadata(os.zones.info()._info)
+    except Exception, e:
+        zone.log_error(e)
+
+class ZoneManager(object):
+    """Keeps the zone states updated."""
+    def __init__(self):
+        self.last_zone_db_check = datetime.min
+        self.zone_states = {}
+
+    def _refresh_from_db(self, context):
+        """Make our zone state map match the db."""
+        # Add/update existing zones ...
+        zones = db.zone_get_all(context)
+        existing = self.zone_states.keys()
+        db_keys = []
+        for zone in zones:
+            db_keys.append(zone.id)
+            if zone.id not in existing:
+                self.zone_states[zone.id] = ZoneState()
+            self.zone_states[zone.id].update_credentials(zone)
+
+        # Cleanup zones removed from db ...
+        for zone_id in self.zone_states.keys():
+            if zone_id not in db_keys:
+                del self.zone_states[zone_id]
+ 
+    def _poll_zones(self, context):
+        """Try to connect to each child zone and get update."""
+        green_pool = GreenPool()
+        green_pool.imap(_poll_zone, self.zone_states.values())
+
+    def ping(self, context=None):
+        """Ping should be called periodically to update zone status."""
+        logging.debug("ZoneManager PING")
+        diff = datetime.now() - self.last_zone_db_check
+        if diff.seconds >=  FLAGS.zone_db_check_interval:
+            logging.debug("ZoneManager RECHECKING DB ")
+            self.last_zone_db_check = datetime.now()
+            self._refresh_from_db(context)
+        self._poll_zones(context)

From 422fefc6792807560c48e4e5a322739ef97ea186 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Wed, 16 Feb 2011 13:17:42 -0800
Subject: [PATCH 04/14] zone manager tests

---
 nova/scheduler/zone_manager.py |   2 +-
 nova/tests/test_zones.py       | 132 +++++++++++++++++++++++++++++++++
 2 files changed, 133 insertions(+), 1 deletion(-)
 create mode 100644 nova/tests/test_zones.py

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index dd910eb0..0974f271 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -71,7 +71,7 @@ class ZoneState(object):
         logging.warning(_("%s error talking to zone %s") % (exception,
             zone.api_url, FLAGS.zone_failures_to_offline))
 
-       self.attempt += 1
+        self.attempt += 1
         if self.attempt >= FLAGS.zone_failures_to_offline:
            self.is_active = False
            logging.error(_("No answer from zone %s after %d "
diff --git a/nova/tests/test_zones.py b/nova/tests/test_zones.py
new file mode 100644
index 00000000..b4c8815d
--- /dev/null
+++ b/nova/tests/test_zones.py
@@ -0,0 +1,132 @@
+# Copyright 2010 United States Government as represented by the
+# Administrator of the National Aeronautics and Space Administration.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+"""
+Tests For ZoneManager
+"""
+
+import datetime
+import mox
+
+from nova import context
+from nova import db
+from nova import flags
+from nova import service
+from nova import test
+from nova import rpc
+from nova import utils
+from nova.auth import manager as auth_manager
+from nova.scheduler import zone_manager
+
+
+class FakeZone:
+    """Represents a fake zone from the db"""
+    def __init__(self, *args, **kwargs):
+        for k, v in kwargs.iteritems():
+            setattr(self, k, v)
+
+
+class ZoneManagerTestCase(test.TestCase):
+    """Test case for zone manager"""
+    def test_ping(self):
+        zm = zone_manager.ZoneManager()
+        self.mox.StubOutWithMock(zm, '_refresh_from_db')
+        self.mox.StubOutWithMock(zm, '_poll_zones')
+        zm._refresh_from_db(mox.IgnoreArg())
+        zm._poll_zones(mox.IgnoreArg())
+
+        self.mox.ReplayAll()
+        zm.ping(None)
+        self.mox.VerifyAll()
+
+    def test_refresh_from_db_new(self):
+        zm = zone_manager.ZoneManager()
+
+        self.mox.StubOutWithMock(db, 'zone_get_all')
+        db.zone_get_all(mox.IgnoreArg()).AndReturn([
+               FakeZone(id=1, api_url='http://foo.com', username='user1',
+                    password='pass1'),
+            ])
+        
+        self.assertEquals(len(zm.zone_states), 0)
+
+        self.mox.ReplayAll()
+        zm._refresh_from_db(None)
+        self.mox.VerifyAll()
+
+        self.assertEquals(len(zm.zone_states), 1)
+        self.assertEquals(zm.zone_states[1].username, 'user1')
+
+    def test_refresh_from_db_replace_existing(self):
+        zm = zone_manager.ZoneManager()
+        zone_state = zone_manager.ZoneState()
+        zone_state.update_credentials(FakeZone(id=1, api_url='http://foo.com',
+                        username='user1', password='pass1'))
+        zm.zone_states[1] = zone_state
+
+        self.mox.StubOutWithMock(db, 'zone_get_all')
+        db.zone_get_all(mox.IgnoreArg()).AndReturn([
+               FakeZone(id=1, api_url='http://foo.com', username='user2',
+                    password='pass2'),
+            ])
+        
+        self.assertEquals(len(zm.zone_states), 1)
+
+        self.mox.ReplayAll()
+        zm._refresh_from_db(None)
+        self.mox.VerifyAll()
+
+        self.assertEquals(len(zm.zone_states), 1)
+        self.assertEquals(zm.zone_states[1].username, 'user2')
+
+    def test_refresh_from_db_missing(self):
+        zm = zone_manager.ZoneManager()
+        zone_state = zone_manager.ZoneState()
+        zone_state.update_credentials(FakeZone(id=1, api_url='http://foo.com',
+                        username='user1', password='pass1'))
+        zm.zone_states[1] = zone_state
+
+        self.mox.StubOutWithMock(db, 'zone_get_all')
+        db.zone_get_all(mox.IgnoreArg()).AndReturn([ ])
+        
+        self.assertEquals(len(zm.zone_states), 1)
+
+        self.mox.ReplayAll()
+        zm._refresh_from_db(None)
+        self.mox.VerifyAll()
+
+        self.assertEquals(len(zm.zone_states), 0)
+
+    def test_refresh_from_db_add_and_delete(self):
+        zm = zone_manager.ZoneManager()
+        zone_state = zone_manager.ZoneState()
+        zone_state.update_credentials(FakeZone(id=1, api_url='http://foo.com',
+                        username='user1', password='pass1'))
+        zm.zone_states[1] = zone_state
+
+        self.mox.StubOutWithMock(db, 'zone_get_all')
+        
+        db.zone_get_all(mox.IgnoreArg()).AndReturn([
+               FakeZone(id=2, api_url='http://foo.com', username='user2',
+                    password='pass2'),
+            ])
+        self.assertEquals(len(zm.zone_states), 1)
+
+        self.mox.ReplayAll()
+        zm._refresh_from_db(None)
+        self.mox.VerifyAll()
+
+        self.assertEquals(len(zm.zone_states), 1)
+        self.assertEquals(zm.zone_states[2].username, 'user2')

From 87e42ad8148bdf9dfe6bc1fa6c4a7bb5eecff021 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Wed, 16 Feb 2011 18:30:56 -0800
Subject: [PATCH 05/14] polling tests

---
 nova/scheduler/zone_manager.py | 15 ++++++++-----
 nova/tests/test_zones.py       | 41 ++++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+), 5 deletions(-)

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index 0974f271..a6bbc2eb 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -68,22 +68,27 @@ class ZoneState(object):
            marked as offline."""
         self.last_exception = exception
         self.last_exception_time = datetime.now()
-        logging.warning(_("%s error talking to zone %s") % (exception,
-            zone.api_url, FLAGS.zone_failures_to_offline))
+        logging.warning(_("'%s' error talking to zone %s") % (exception,
+            self.api_url))
 
         self.attempt += 1
         if self.attempt >= FLAGS.zone_failures_to_offline:
            self.is_active = False
            logging.error(_("No answer from zone %s after %d "
-               "attempts. Marking inactive.") % (zone.api_url,
+               "attempts. Marking inactive.") % (self.api_url,
                FLAGS.zone_failures_to_offline))
 
+
+def _call_novatools(zone):
+    """Call novatools. Broken out for testing purposes."""
+    os = novatools.OpenStack(zone.username, zone.password, zone.api_url)
+    return os.zones.info()._info
+
 def _poll_zone(zone):
     """Eventlet worker to poll a zone."""
     logging.debug("_POLL_ZONE: STARTING")
-    os = novatools.OpenStack(zone.username, zone.password, zone.api_url)
     try:
-        zone.update_metadata(os.zones.info()._info)
+        zone.update_metadata(_call_novatools(zone))
     except Exception, e:
         zone.log_error(e)
 
diff --git a/nova/tests/test_zones.py b/nova/tests/test_zones.py
index b4c8815d..2cb070ac 100644
--- a/nova/tests/test_zones.py
+++ b/nova/tests/test_zones.py
@@ -19,6 +19,7 @@ Tests For ZoneManager
 
 import datetime
 import mox
+import novatools
 
 from nova import context
 from nova import db
@@ -30,6 +31,8 @@ from nova import utils
 from nova.auth import manager as auth_manager
 from nova.scheduler import zone_manager
 
+FLAGS = flags.FLAGS
+
 
 class FakeZone:
     """Represents a fake zone from the db"""
@@ -38,6 +41,11 @@ class FakeZone:
             setattr(self, k, v)
 
 
+def exploding_novatools(zone):
+    """Used when we want to simulate a novatools call failing."""
+    raise Exception("kaboom")
+
+
 class ZoneManagerTestCase(test.TestCase):
     """Test case for zone manager"""
     def test_ping(self):
@@ -130,3 +138,36 @@ class ZoneManagerTestCase(test.TestCase):
 
         self.assertEquals(len(zm.zone_states), 1)
         self.assertEquals(zm.zone_states[2].username, 'user2')
+
+    def test_poll_zone(self):
+        self.mox.StubOutWithMock(zone_manager, '_call_novatools')
+        zone_manager._call_novatools(mox.IgnoreArg()).AndReturn(
+                        dict(name='zohan', capabilities='hairdresser'))
+
+        zone_state = zone_manager.ZoneState()
+        zone_state.update_credentials(FakeZone(id=2,
+                       api_url='http://foo.com', username='user2',
+                       password='pass2'))
+        zone_state.attempt = 1
+
+        self.mox.ReplayAll()
+        zone_manager._poll_zone(zone_state)
+        self.mox.VerifyAll()
+        self.assertEquals(zone_state.attempt, 0)
+        self.assertEquals(zone_state.name, 'zohan')
+
+    def test_poll_zone_fails(self):
+        self.stubs.Set(zone_manager, "_call_novatools", exploding_novatools)
+
+        zone_state = zone_manager.ZoneState()
+        zone_state.update_credentials(FakeZone(id=2,
+                       api_url='http://foo.com', username='user2',
+                       password='pass2'))
+        zone_state.attempt = FLAGS.zone_failures_to_offline - 1
+
+        self.mox.ReplayAll()
+        zone_manager._poll_zone(zone_state)
+        self.mox.VerifyAll()
+        self.assertEquals(zone_state.attempt, 3)
+        self.assertFalse(zone_state.is_active)
+        self.assertEquals(zone_state.name, None)

From 7f2bf2dd717f08cce60ce0db87c719aeb3104031 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Wed, 16 Feb 2011 18:35:43 -0800
Subject: [PATCH 06/14] style cleanup

---
 nova/scheduler/zone_manager.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index a6bbc2eb..a35acb00 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -84,14 +84,16 @@ def _call_novatools(zone):
     os = novatools.OpenStack(zone.username, zone.password, zone.api_url)
     return os.zones.info()._info
 
+
 def _poll_zone(zone):
     """Eventlet worker to poll a zone."""
-    logging.debug("_POLL_ZONE: STARTING")
+    logging.debug(_("Polling zone: %s") % zone.api_url)
     try:
         zone.update_metadata(_call_novatools(zone))
     except Exception, e:
         zone.log_error(e)
 
+
 class ZoneManager(object):
     """Keeps the zone states updated."""
     def __init__(self):
@@ -122,10 +124,9 @@ class ZoneManager(object):
 
     def ping(self, context=None):
         """Ping should be called periodically to update zone status."""
-        logging.debug("ZoneManager PING")
         diff = datetime.now() - self.last_zone_db_check
         if diff.seconds >=  FLAGS.zone_db_check_interval:
-            logging.debug("ZoneManager RECHECKING DB ")
+            logging.debug("Updating zone cache from db.")
             self.last_zone_db_check = datetime.now()
             self._refresh_from_db(context)
         self._poll_zones(context)

From 258916bbe5356c2658ff1e8a452e324c753f02b4 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Thu, 17 Feb 2011 12:12:19 -0800
Subject: [PATCH 07/14] zone list now comes from scheduler zonemanager

---
 nova/scheduler/zone_manager.py | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index a35acb00..4fa52897 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -21,6 +21,7 @@ ZoneManager oversees all communications with child Zones.
 
 import novatools
 import thread
+import traceback
 
 from datetime import datetime
 from eventlet.greenpool import GreenPool
@@ -63,6 +64,11 @@ class ZoneState(object):
         self.capabilities = zone_metadata["capabilities"]
         self.is_active = True
 
+    def to_dict(self):
+        return dict(name=self.name, capabilities=self.capabilities,
+                    is_active=self.is_active, api_url=self.api_url,
+                    id=self.zone_id)
+
     def log_error(self, exception):
         """Something went wrong. Check to see if zone should be
            marked as offline."""
@@ -91,7 +97,7 @@ def _poll_zone(zone):
     try:
         zone.update_metadata(_call_novatools(zone))
     except Exception, e:
-        zone.log_error(e)
+        zone.log_error(traceback.format_exc())
 
 
 class ZoneManager(object):
@@ -100,6 +106,9 @@ class ZoneManager(object):
         self.last_zone_db_check = datetime.min
         self.zone_states = {}
 
+    def get_zone_list(self):
+        return [ zone.to_dict() for zone in self.zone_states.values() ]
+
     def _refresh_from_db(self, context):
         """Make our zone state map match the db."""
         # Add/update existing zones ...

From ad006c20e0f5db31df11bd8a6a50c5e0d54623c2 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Thu, 17 Feb 2011 16:18:03 -0400
Subject: [PATCH 08/14] fixup

---
 bin/nova-combined              |  4 ++--
 nova/flags.py                  |  2 +-
 nova/scheduler/zone_manager.py | 18 +++++++++---------
 nova/tests/test_zones.py       | 10 +++++-----
 4 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/bin/nova-combined b/bin/nova-combined
index a0f552d6..913c866b 100755
--- a/bin/nova-combined
+++ b/bin/nova-combined
@@ -53,11 +53,11 @@ if __name__ == '__main__':
 
     compute = service.Service.create(binary='nova-compute')
     network = service.Service.create(binary='nova-network')
-    #volume = service.Service.create(binary='nova-volume')
+    volume = service.Service.create(binary='nova-volume')
     scheduler = service.Service.create(binary='nova-scheduler')
     #objectstore = service.Service.create(binary='nova-objectstore')
 
-    service.serve(compute, network, scheduler)
+    service.serve(compute, network, volume, scheduler)
 
     apps = []
     paste_config_file = wsgi.paste_config_file('nova-api.conf')
diff --git a/nova/flags.py b/nova/flags.py
index 0a45499f..60d7cdd0 100644
--- a/nova/flags.py
+++ b/nova/flags.py
@@ -314,6 +314,6 @@ DEFINE_string('node_availability_zone', 'nova',
               'availability zone of this node')
 
 DEFINE_string('zone_name', 'nova', 'name of this zone')
-DEFINE_string('zone_capabilities', 'xen, linux', 
+DEFINE_string('zone_capabilities', 'xen, linux',
               'comma-delimited list of tags which represent boolean'
               ' capabilities of this zone')
diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index 4fa52897..e7c37a9a 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -47,14 +47,14 @@ class ZoneState(object):
         self.last_seen = datetime.min
         self.last_exception = None
         self.last_exception_time = None
- 
+
     def update_credentials(self, zone):
         """Update zone credentials from db"""
         self.zone_id = zone.id
         self.api_url = zone.api_url
         self.username = zone.username
         self.password = zone.password
- 
+
     def update_metadata(self, zone_metadata):
         """Update zone metadata after successful communications with
            child zone."""
@@ -79,10 +79,10 @@ class ZoneState(object):
 
         self.attempt += 1
         if self.attempt >= FLAGS.zone_failures_to_offline:
-           self.is_active = False
-           logging.error(_("No answer from zone %s after %d "
-               "attempts. Marking inactive.") % (self.api_url,
-               FLAGS.zone_failures_to_offline))
+            self.is_active = False
+            logging.error(_("No answer from zone %s after %d "
+                "attempts. Marking inactive.") % (self.api_url,
+                FLAGS.zone_failures_to_offline))
 
 
 def _call_novatools(zone):
@@ -107,7 +107,7 @@ class ZoneManager(object):
         self.zone_states = {}
 
     def get_zone_list(self):
-        return [ zone.to_dict() for zone in self.zone_states.values() ]
+        return [zone.to_dict() for zone in self.zone_states.values()]
 
     def _refresh_from_db(self, context):
         """Make our zone state map match the db."""
@@ -125,7 +125,7 @@ class ZoneManager(object):
         for zone_id in self.zone_states.keys():
             if zone_id not in db_keys:
                 del self.zone_states[zone_id]
- 
+
     def _poll_zones(self, context):
         """Try to connect to each child zone and get update."""
         green_pool = GreenPool()
@@ -134,7 +134,7 @@ class ZoneManager(object):
     def ping(self, context=None):
         """Ping should be called periodically to update zone status."""
         diff = datetime.now() - self.last_zone_db_check
-        if diff.seconds >=  FLAGS.zone_db_check_interval:
+        if diff.seconds >= FLAGS.zone_db_check_interval:
             logging.debug("Updating zone cache from db.")
             self.last_zone_db_check = datetime.now()
             self._refresh_from_db(context)
diff --git a/nova/tests/test_zones.py b/nova/tests/test_zones.py
index 2cb070ac..7036ebe5 100644
--- a/nova/tests/test_zones.py
+++ b/nova/tests/test_zones.py
@@ -67,7 +67,7 @@ class ZoneManagerTestCase(test.TestCase):
                FakeZone(id=1, api_url='http://foo.com', username='user1',
                     password='pass1'),
             ])
-        
+
         self.assertEquals(len(zm.zone_states), 0)
 
         self.mox.ReplayAll()
@@ -89,7 +89,7 @@ class ZoneManagerTestCase(test.TestCase):
                FakeZone(id=1, api_url='http://foo.com', username='user2',
                     password='pass2'),
             ])
-        
+
         self.assertEquals(len(zm.zone_states), 1)
 
         self.mox.ReplayAll()
@@ -107,8 +107,8 @@ class ZoneManagerTestCase(test.TestCase):
         zm.zone_states[1] = zone_state
 
         self.mox.StubOutWithMock(db, 'zone_get_all')
-        db.zone_get_all(mox.IgnoreArg()).AndReturn([ ])
-        
+        db.zone_get_all(mox.IgnoreArg()).AndReturn([])
+
         self.assertEquals(len(zm.zone_states), 1)
 
         self.mox.ReplayAll()
@@ -125,7 +125,7 @@ class ZoneManagerTestCase(test.TestCase):
         zm.zone_states[1] = zone_state
 
         self.mox.StubOutWithMock(db, 'zone_get_all')
-        
+
         db.zone_get_all(mox.IgnoreArg()).AndReturn([
                FakeZone(id=2, api_url='http://foo.com', username='user2',
                     password='pass2'),

From c1e9865d4e573ea8d66bbf221d89ea6c22f892a2 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Thu, 17 Feb 2011 13:23:56 -0800
Subject: [PATCH 09/14] multi positional string fix

---
 nova/scheduler/zone_manager.py | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index e7c37a9a..af0b90f9 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -74,15 +74,17 @@ class ZoneState(object):
            marked as offline."""
         self.last_exception = exception
         self.last_exception_time = datetime.now()
-        logging.warning(_("'%s' error talking to zone %s") % (exception,
-            self.api_url))
+        api_url = self.api_url
+        logging.warning(_("'%(exception)s' error talking to "
+                          "zone %(api_url)s") % locals())
 
+        max_errors = FLAGS.zone_failures_to_offline:
         self.attempt += 1
-        if self.attempt >= FLAGS.zone_failures_to_offline:
+        if self.attempt >= max_errors:
             self.is_active = False
-            logging.error(_("No answer from zone %s after %d "
-                "attempts. Marking inactive.") % (self.api_url,
-                FLAGS.zone_failures_to_offline))
+            logging.error(_("No answer from zone %(api_url)s "
+                            "after %(max_errors)d "
+                            "attempts. Marking inactive.") % locals())
 
 
 def _call_novatools(zone):

From f8331adfce4f370608ea2c9ef451461099fde5d3 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Thu, 17 Feb 2011 13:29:19 -0800
Subject: [PATCH 10/14] fixed strings

---
 nova/scheduler/zone_manager.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index af0b90f9..4bf6e36c 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -78,7 +78,7 @@ class ZoneState(object):
         logging.warning(_("'%(exception)s' error talking to "
                           "zone %(api_url)s") % locals())
 
-        max_errors = FLAGS.zone_failures_to_offline:
+        max_errors = FLAGS.zone_failures_to_offline
         self.attempt += 1
         if self.attempt >= max_errors:
             self.is_active = False

From d0d933708b9bec232f023f3bc9615f751541002d Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Thu, 17 Feb 2011 18:49:30 -0400
Subject: [PATCH 11/14] missing docstring and fixed copyrights

---
 nova/scheduler/zone_manager.py | 3 +--
 nova/tests/test_zones.py       | 1 -
 2 files changed, 1 insertion(+), 3 deletions(-)

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index 4bf6e36c..3e7c1eba 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -1,6 +1,4 @@
 # Copyright (c) 2010 Openstack, LLC.
-# Copyright 2010 United States Government as represented by the
-# Administrator of the National Aeronautics and Space Administration.
 # All Rights Reserved.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -109,6 +107,7 @@ class ZoneManager(object):
         self.zone_states = {}
 
     def get_zone_list(self):
+        """Return the list of zones we know about."""
         return [zone.to_dict() for zone in self.zone_states.values()]
 
     def _refresh_from_db(self, context):
diff --git a/nova/tests/test_zones.py b/nova/tests/test_zones.py
index 7036ebe5..c273230a 100644
--- a/nova/tests/test_zones.py
+++ b/nova/tests/test_zones.py
@@ -1,5 +1,4 @@
 # Copyright 2010 United States Government as represented by the
-# Administrator of the National Aeronautics and Space Administration.
 # All Rights Reserved.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may

From f4397b0b9409d8c32fd454f1a3cf538e0af1d9dc Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Fri, 18 Feb 2011 12:08:35 -0400
Subject: [PATCH 12/14] fixups backed on merge comments

---
 nova/flags.py                  |  5 ++--
 nova/scheduler/api.py          | 49 ++++++++++++++++++++++++++++++++++
 nova/scheduler/zone_manager.py | 15 ++++++-----
 3 files changed, 59 insertions(+), 10 deletions(-)
 create mode 100644 nova/scheduler/api.py

diff --git a/nova/flags.py b/nova/flags.py
index 7e4919d6..41f01fcd 100644
--- a/nova/flags.py
+++ b/nova/flags.py
@@ -316,6 +316,5 @@ DEFINE_string('node_availability_zone', 'nova',
               'availability zone of this node')
 
 DEFINE_string('zone_name', 'nova', 'name of this zone')
-DEFINE_string('zone_capabilities', 'xen, linux',
-              'comma-delimited list of tags which represent boolean'
-              ' capabilities of this zone')
+DEFINE_string('zone_capabilities', 'kypervisor:xenserver;os:linux',
+              'Key/Value tags which represent capabilities of this zone')
diff --git a/nova/scheduler/api.py b/nova/scheduler/api.py
new file mode 100644
index 00000000..8491bf3a
--- /dev/null
+++ b/nova/scheduler/api.py
@@ -0,0 +1,49 @@
+# Copyright (c) 2011 Openstack, LLC.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""
+Handles all requests relating to schedulers.
+"""
+
+from nova import flags
+from nova import log as logging
+from nova import rpc
+
+FLAGS = flags.FLAGS
+LOG = logging.getLogger('nova.scheduler.api')
+
+
+class API:
+    """API for interacting with the scheduler."""
+
+    def _call_scheduler(self, method, context, params=None):
+        """Generic handler for RPC calls to the scheduler.
+
+        :param params: Optional dictionary of arguments to be passed to the
+                       scheduler worker
+
+        :retval: Result returned by scheduler worker
+        """
+        if not params:
+            params = {}
+        queue = FLAGS.scheduler_topic
+        kwargs = {'method': method, 'args': params}
+        return rpc.call(context, queue, kwargs)
+
+    def get_zone_list(self, context):
+        items = self._call_scheduler('get_zone_list', context)
+        for item in items:
+            item['api_url'] = item['api_url'].replace('\\/', '/')
+        return items
diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index 3e7c1eba..783783d0 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2010 Openstack, LLC.
+# Copyright (c) 2011 Openstack, LLC.
 # All Rights Reserved.
 #
 #    Licensed under the Apache License, Version 2.0 (the "License"); you may
@@ -87,8 +87,8 @@ class ZoneState(object):
 
 def _call_novatools(zone):
     """Call novatools. Broken out for testing purposes."""
-    os = novatools.OpenStack(zone.username, zone.password, zone.api_url)
-    return os.zones.info()._info
+    client = novatools.OpenStack(zone.username, zone.password, zone.api_url)
+    return client.zones.info()._info
 
 
 def _poll_zone(zone):
@@ -105,6 +105,7 @@ class ZoneManager(object):
     def __init__(self):
         self.last_zone_db_check = datetime.min
         self.zone_states = {}
+        self.green_pool = GreenPool()
 
     def get_zone_list(self):
         """Return the list of zones we know about."""
@@ -123,20 +124,20 @@ class ZoneManager(object):
             self.zone_states[zone.id].update_credentials(zone)
 
         # Cleanup zones removed from db ...
-        for zone_id in self.zone_states.keys():
+        keys = self.zone_states.keys()  # since we're deleting
+        for zone_id in keys:
             if zone_id not in db_keys:
                 del self.zone_states[zone_id]
 
     def _poll_zones(self, context):
         """Try to connect to each child zone and get update."""
-        green_pool = GreenPool()
-        green_pool.imap(_poll_zone, self.zone_states.values())
+        self.green_pool.imap(_poll_zone, self.zone_states.values())
 
     def ping(self, context=None):
         """Ping should be called periodically to update zone status."""
         diff = datetime.now() - self.last_zone_db_check
         if diff.seconds >= FLAGS.zone_db_check_interval:
-            logging.debug("Updating zone cache from db.")
+            logging.debug(_("Updating zone cache from db."))
             self.last_zone_db_check = datetime.now()
             self._refresh_from_db(context)
         self._poll_zones(context)

From e0e1022f91d94648f3ef54efab61b023587bb086 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Fri, 18 Feb 2011 17:45:57 -0400
Subject: [PATCH 13/14] sandy y u no read hacking guide and import classes?

---
 nova/scheduler/zone_manager.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/nova/scheduler/zone_manager.py b/nova/scheduler/zone_manager.py
index 783783d0..758c5e3d 100644
--- a/nova/scheduler/zone_manager.py
+++ b/nova/scheduler/zone_manager.py
@@ -22,7 +22,7 @@ import thread
 import traceback
 
 from datetime import datetime
-from eventlet.greenpool import GreenPool
+from eventlet import greenpool
 
 from nova import db
 from nova import flags
@@ -105,7 +105,7 @@ class ZoneManager(object):
     def __init__(self):
         self.last_zone_db_check = datetime.min
         self.zone_states = {}
-        self.green_pool = GreenPool()
+        self.green_pool = greenpool.GreenPool()
 
     def get_zone_list(self):
         """Return the list of zones we know about."""

From 53fcfc1cc5bc7b647ba8c096f3b7a9cc9527cbc8 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Fri, 25 Feb 2011 13:40:15 -0800
Subject: [PATCH 14/14] API changed to new style class

---
 nova/scheduler/api.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/nova/scheduler/api.py b/nova/scheduler/api.py
index 8491bf3a..2405f134 100644
--- a/nova/scheduler/api.py
+++ b/nova/scheduler/api.py
@@ -25,7 +25,7 @@ FLAGS = flags.FLAGS
 LOG = logging.getLogger('nova.scheduler.api')
 
 
-class API:
+class API(object):
     """API for interacting with the scheduler."""
 
     def _call_scheduler(self, method, context, params=None):