From 6d04d6e17f753e0573d37992576dedccccf9db93 Mon Sep 17 00:00:00 2001
From: Sandy Walsh <sandy.walsh@rackspace.com>
Date: Fri, 13 May 2011 10:43:43 -0700
Subject: started on integrating HostFilter

---
 nova/scheduler/host_filter.py          | 18 ++++++++++++++++++
 nova/scheduler/zone_aware_scheduler.py | 16 ++++++++++++----
 2 files changed, 30 insertions(+), 4 deletions(-)

diff --git a/nova/scheduler/host_filter.py b/nova/scheduler/host_filter.py
index 483f3225c..17f63d4a0 100644
--- a/nova/scheduler/host_filter.py
+++ b/nova/scheduler/host_filter.py
@@ -286,3 +286,21 @@ def choose_driver(driver_name=None):
         if "%s.%s" % (driver.__module__, driver.__name__) == driver_name:
             return driver()
     raise exception.SchedulerHostFilterDriverNotFound(driver_name=driver_name)
+
+
+class HostFilterScheduler(ZoneAwareScheduler):
+    """The HostFilterScheduler uses the HostFilter drivers to filter
+    hosts for weighing. The particular driver used may be passed in
+    as an argument or the default will be used."""
+
+    def filter_hosts(self, num, specs):
+        """Filter the full host list (from the ZoneManager)"""
+        driver_name = specs.get("filter_driver", None)
+        driver = host_filter.choose_driver(driver_name)
+
+        # TODO(sandy): We're only using InstanceType-based specs
+        # currently. Later we'll need to snoop for more detailed
+        # host filter requests.
+        instance_type = specs['instance_type']
+        query = driver.instance_type_to_filter(query)
+        return driver.filter_hosts(self.zone_manager, query)
diff --git a/nova/scheduler/zone_aware_scheduler.py b/nova/scheduler/zone_aware_scheduler.py
index b3d230bd2..fde8b6792 100644
--- a/nova/scheduler/zone_aware_scheduler.py
+++ b/nova/scheduler/zone_aware_scheduler.py
@@ -25,6 +25,7 @@ import operator
 from nova import log as logging
 from nova.scheduler import api
 from nova.scheduler import driver
+from nova.scheduler import host_filter
 
 LOG = logging.getLogger('nova.scheduler.zone_aware_scheduler')
 
@@ -36,7 +37,7 @@ class ZoneAwareScheduler(driver.Scheduler):
         """Call novaclient zone method. Broken out for testing."""
         return api.call_zone_method(context, method, specs=specs)
 
-    def schedule_run_instance(self, context, topic='compute', specs={},
+    def schedule_run_instance(self, context, instance_id, instance_type,
                                         *args, **kwargs):
         """This method is called from nova.compute.api to provision
         an instance. However we need to look at the parameters being
@@ -46,6 +47,9 @@ class ZoneAwareScheduler(driver.Scheduler):
            to simply create the instance (either in this zone or
            a child zone)."""
 
+        # TODO(sandy): We'll have to look for richer specs at some point.
+        specs = instance_type
+
         if 'blob' in specs:
             return self.provision_instance(context, topic, specs)
 
@@ -58,7 +62,7 @@ class ZoneAwareScheduler(driver.Scheduler):
         """Create the requested instance in this Zone or a child zone."""
         pass
 
-    def select(self, context, *args, **kwargs):
+    def select(self, context, specs, *args, **kwargs):
         """Select returns a list of weights and zone/host information
         corresponding to the best hosts to service the request. Any
         child zone information has been encrypted so as not to reveal
@@ -80,9 +84,13 @@ class ZoneAwareScheduler(driver.Scheduler):
         ordered by their fitness.
         """
 
-        #TODO(sandy): extract these from args.
+        if topic != "compute":
+            raise NotImplemented(_("Zone Aware Scheduler only understands "
+                                   "Compute nodes (for now)"))
+
+        specs = args['instance_type']
+        #TODO(sandy): how to infer this from OS API params?
         num_instances = 1
-        specs = {}
 
         # Filter local hosts based on requirements ...
         host_list = self.filter_hosts(num_instances, specs)
-- 
cgit