Update storage pools when VMs are created or removed.

cloudcontrol/node/hypervisor/__init__.py

@@ -602,7 +602,7 @@ class Hypervisor(object):
         self.vir_con = libvirt.open('qemu:///system')  # currently only support KVM
 
         # findout storage
-        self.storage = StorageIndex(self.vir_con)
+        self.storage = StorageIndex(handler, self.vir_con)
 
         logger.debug('Storages: %s', self.storage.paths)
 
@@ -652,6 +652,8 @@ class Hypervisor(object):
         event = EVENTS[event]
 
         if event == 'Added':
+            # update Storage pools in case VM has volumes that were created
+            self.storage.update()
             if dom.name() in self.domains:
                 # sometimes libvirt send us the same event multiple times
                 # this can be the result of a change in the domain configuration
@@ -667,6 +669,8 @@ class Hypervisor(object):
             vm = self.domains.pop(dom.name())
             logger.info('Removed domain %s', vm.name)
             self.handler.tag_db.remove_sub_object(vm.name)
+            # update Storage pools in case VM had volumes that were deleted
+            self.storage.update()
         elif event in ('Started', 'Suspended', 'Resumed', 'Stopped', 'Saved',
                        'Restored'):
             vm = self.domains.get(dom.name())
@@ -726,10 +730,13 @@ class Hypervisor(object):
 
 class StorageIndex(object):
     """Keep an index of all storage volume paths."""
-    def __init__(self, lv_con):
+    def __init__(self, handler, lv_con):
         """
+        :param handler: Hypervisor handler instance
         :param lv_con: Libvirt connection
         """
+        self.handler = handler
+        self.lv_con = lv_con
         self.storages = dict(
             (s.name, s) for s in imap(
                 Storage,
@@ -743,6 +750,40 @@ class StorageIndex(object):
             ),
         )
 
+        self.paths = None
+        self.update_path_index()
+
+
+    def update(self):
+        """Update storage pools and volumes."""
+        # go through all storage pools and check if it is already in the index
+        for lv_storage in imap(
+            self.lv_con.storagePoolLookupByName,
+            chain(
+                self.lv_con.listDefinedStoragePools(),
+                self.lv_con.listStoragePools(),
+            ),
+        ):
+            if lv_storage.name() in self.storages:
+                # update
+                self.storages[lv_storage.name()].update()
+            else:
+                # add storage pool
+                s = Storage(lv_storage)
+                self.storages[s.name] = s
+                # add tags
+                self.handler.tag_db.add_tags((
+                    Tag('sto%s_state' % s.name, lambda: s.state, 5, 5),
+                    Tag('sto%s_size' % s.name, lambda: s.capacity, 5, 5),
+                    Tag('sto%s_free' % s.name, lambda: s.available, 5, 5),
+                    Tag('sto%s_used' % s.name,
+                        lambda: s.capacity - s.available, 5, 5),
+                    Tag('sto%s_type' % s.name, lambda: s.type, 5, 5),
+                ))
+
+        self.update_path_index()
+
+    def update_path_index(self):
         self.paths = dict(
             (v.path, v) for v in chain.from_iterable(imap(
                 lambda s: s.volumes.itervalues(),
@@ -825,8 +866,8 @@ class Storage(object):
         self.name = lv_storage.name()
         self.lv_storage = lv_storage
 
-        self.state, self.capacity, self.allocation, self.available = lv_storage.info()
-        self.state = STORAGE_STATES[self.state]
+        self.state, self.capacity = None, None
+        self.allocation, self.available = None, None
 
         self.type = et.ElementTree().parse(
             StringIO(lv_storage.XMLDesc(0))).get('type')
@@ -837,6 +878,29 @@ class Storage(object):
              lv_storage.listVolumes()),
         ))
 
+        self.update_attr()
+
+    def update(self):
+        self.update_attr()
+
+        # update volumes
+        for vol_name in self.lv_storage.listVolumes():
+            if vol_name in self.volumes:
+                # update volume
+                self.volumes[vol_name].update()
+            else:
+                # add volume
+                v = Volume(self.lv_storage.storageVolLookupByName(vol_name))
+                self.volumes[v.name] = v
+
+    def update_attr(self):
+        self.state, self.capacity, self.allocation, self.available = self.lv_storage.info()
+        self.state = STORAGE_STATES[self.state]
+
+        self.type = et.ElementTree().parse(
+            StringIO(self.lv_storage.XMLDesc(0))).get('type')
+
+
 
 class Volume(object):
     """Volume abstraction."""
@@ -847,5 +911,9 @@ class Volume(object):
         self.storage = lv_volume.storagePoolLookupByVolume().name()
         self.path = lv_volume.path()
         self.name = lv_volume.name()
-        self.capacity, self.allocation = lv_volume.info()[1:]
+        self.capacity, self.allocation = None, None
         self.lv_volume = lv_volume
+        self.update()
+
+    def update(self):
+        self.capacity, self.allocation = self.lv_volume.info()[1:]