General host aggregates part 2

Partially implements blueprint general-host-aggregates: Scheduler Filter
* Add AggregateInstanceExtraSpecsFilter
* change db.aggregate_get_by_host to return a list of aggregates
  instead of the first aggregate
* Add optional key filter to db.aggregate_get_by_host along with test
* Add db.aggregate_metadata_get_by_host to get host aggregate metadata
* add optional key filter to db.aggregate_metadata_get_by_host
* Add AggregateTypeAffinityFilter

Change-Id: I4a3061276cc3b0c5c695eaf973b773183b3c4f4b

5 files changed, 25 insertions, 16 deletions

diff --git a/nova/virt/xenapi/driver.py b/nova/virt/xenapi/driver.py
index ac4547166..28beffc80 100644
--- a/nova/virt/xenapi/driver.py
+++ b/nova/virt/xenapi/driver.py
@@ -54,11 +54,11 @@ from nova.openstack.common import log as logging
 from nova.virt import driver
 from nova.virt.xenapi import host
 from nova.virt.xenapi import pool
+from nova.virt.xenapi import pool_states
 from nova.virt.xenapi import vm_utils
 from nova.virt.xenapi import vmops
 from nova.virt.xenapi import volumeops
 
-
 LOG = logging.getLogger(__name__)
 
 xenapi_opts = [
@@ -621,13 +621,12 @@ class XenAPISession(object):
 
     def _get_host_uuid(self):
         if self.is_slave:
-            try:
-                aggr = db.aggregate_get_by_host(context.get_admin_context(),
-                                                FLAGS.host)
-            except exception.AggregateHostNotFound:
-                LOG.exception(_('Host is member of a pool, but DB '
+            aggr = db.aggregate_get_by_host(context.get_admin_context(),
+                    FLAGS.host, key=pool_states.POOL_FLAG)[0]
+            if not aggr:
+                LOG.error(_('Host is member of a pool, but DB '
                                 'says otherwise'))
-                raise
+                raise exception.AggregateHostNotFound()
             return aggr.metadetails[FLAGS.host]
         else:
             with self._get_session() as session:
diff --git a/nova/virt/xenapi/host.py b/nova/virt/xenapi/host.py
index df6b4f85d..b45a9106c 100644
--- a/nova/virt/xenapi/host.py
+++ b/nova/virt/xenapi/host.py
@@ -28,6 +28,7 @@ from nova import db
 from nova import exception
 from nova import notifications
 from nova.openstack.common import jsonutils
+from nova.virt.xenapi import pool_states
 from nova.virt.xenapi import vm_utils
 
 LOG = logging.getLogger(__name__)
@@ -210,7 +211,10 @@ def _host_find(context, session, src, dst):
     # NOTE: this would be a lot simpler if nova-compute stored
     # FLAGS.host in the XenServer host's other-config map.
     # TODO(armando-migliaccio): improve according the note above
-    aggregate = db.aggregate_get_by_host(context, src)
+    aggregate = db.aggregate_get_by_host(context, src,
+            key=pool_states.POOL_FLAG)[0]
+    if not aggregate:
+        raise exception.AggregateHostNotFound(host=src)
     uuid = session.call_xenapi('host.get_record', dst)['uuid']
     for compute_host, host_uuid in aggregate.metadetails.iteritems():
         if host_uuid == uuid:
diff --git a/nova/virt/xenapi/pool.py b/nova/virt/xenapi/pool.py
index 05592f978..d7204d372 100644
--- a/nova/virt/xenapi/pool.py
+++ b/nova/virt/xenapi/pool.py
@@ -67,14 +67,9 @@ class ResourcePool(object):
             LOG.exception(_('Aggregate %(aggregate_id)s: unrecoverable state '
                             'during operation on %(host)s') % locals())
 
-    def _is_hv_pool(self, context, aggregate_id):
-        """Checks if aggregate is a hypervisor_pool"""
-        metadata = db.aggregate_metadata_get(context, aggregate_id)
-        return pool_states.POOL_FLAG in metadata.keys()
-
     def add_to_aggregate(self, context, aggregate, host, **kwargs):
         """Add a compute host to an aggregate."""
-        if not self._is_hv_pool(context, aggregate.id):
+        if not pool_states.is_hv_pool(context, aggregate.id):
             return
 
         invalid = {pool_states.CHANGING: 'setup in progress',
@@ -126,7 +121,7 @@ class ResourcePool(object):
 
     def remove_from_aggregate(self, context, aggregate, host, **kwargs):
         """Remove a compute host from an aggregate."""
-        if not self._is_hv_pool(context, aggregate.id):
+        if not pool_states.is_hv_pool(context, aggregate.id):
             return
 
         invalid = {pool_states.CREATED: 'no hosts to remove',
diff --git a/nova/virt/xenapi/pool_states.py b/nova/virt/xenapi/pool_states.py
index 5b3765cfc..82a85ce14 100644
--- a/nova/virt/xenapi/pool_states.py
+++ b/nova/virt/xenapi/pool_states.py
@@ -36,6 +36,7 @@ an 'active' pool goes into an 'error' state. To recover from such a state,
 admin intervention is required. Currently an error state is irreversible,
 that is, in order to recover from it an pool must be deleted.
 """
+from nova import db
 
 CREATED = 'created'
 CHANGING = 'changing'
@@ -46,3 +47,9 @@ DISMISSED = 'dismissed'
 # Metadata keys
 KEY = 'operational_state'
 POOL_FLAG = 'hypervisor_pool'
+
+
+def is_hv_pool(context, aggregate_id):
+    """Checks if aggregate is a hypervisor_pool"""
+    metadata = db.aggregate_metadata_get(context, aggregate_id)
+    return POOL_FLAG in metadata.keys()
diff --git a/nova/virt/xenapi/vmops.py b/nova/virt/xenapi/vmops.py
index 8d443f498..abac03d57 100644
--- a/nova/virt/xenapi/vmops.py
+++ b/nova/virt/xenapi/vmops.py
@@ -44,6 +44,7 @@ from nova import utils
 from nova.virt import driver
 from nova.virt.xenapi import agent
 from nova.virt.xenapi import firewall
+from nova.virt.xenapi import pool_states
 from nova.virt.xenapi import vm_utils
 from nova.virt.xenapi import volume_utils
 
@@ -1450,7 +1451,10 @@ class VMOps(object):
                                                network_info=network_info)
 
     def _get_host_uuid_from_aggregate(self, context, hostname):
-        current_aggregate = db.aggregate_get_by_host(context, FLAGS.host)
+        current_aggregate = db.aggregate_get_by_host(context, FLAGS.host,
+               key=pool_states.POOL_FLAG)[0]
+        if not current_aggregate:
+            raise exception.AggregateHostNotFound(host=FLAGS.host)
         try:
             return current_aggregate.metadetails[hostname]
         except KeyError: