Add resource metadata to nodes

We currently don't really have statistics about the resource
utilization of projects or tenants in zuul. This can be solved by
adding resource metadata to the node data structure that can be used
by zuul (which has the knowledge about projects and tenants) to report
resource usage statistics.

The new introduced optional resources field is a plain dict and could
be extended in the future with further resource information like ports
or volume size that might be useful in the future.

This change is fully backwards compatible and doesn't need a total
shutdown of nodepool to upgrade.

Change-Id: I670d4bfd7d35ce1109b3ee9b3342fb45ee283a79

nodepool/driver/openstack/handler.py

@@ -142,6 +142,11 @@ class OpenStackNodeLauncher(NodeLauncher):
         self.node.external_id = server.id
         self.node.hostname = hostname
         self.node.image_id = image_id
+
+        pool = self.handler.provider.pools.get(self.node.pool)
+        resources = self.handler.manager.quotaNeededByNodeType(
+            self.node.type[0], pool)
+        self.node.resources = resources.quota['compute']
         if username:
             self.node.username = username
         self.node.connection_type = connection_type

nodepool/tests/unit/test_launcher.py

@@ -70,6 +70,12 @@ class TestLauncher(tests.DBTestCase):
                                               image.provider_name),
                 id=image.id)
             self.assertEqual(node.image_id, p)
+            resources = {
+                'cores': 4,
+                'instances': 1,
+                'ram': 8192,
+            }
+            self.assertEqual(node.resources, resources)
             self.zk.lockNode(node, blocking=False)
             self.zk.unlockNode(node)
 

nodepool/zk.py

@@ -515,6 +515,7 @@ class Node(BaseModel):
         self.connection_type = None
         self.host_keys = []
         self.hold_expiration = None
+        self.resources = None
 
     def __repr__(self):
         d = self.toDict()
@@ -549,7 +550,8 @@ class Node(BaseModel):
                     self.connection_type == other.connection_type and
                     self.connection_port == other.connection_port and
                     self.host_keys == other.host_keys and
-                    self.hold_expiration == other.hold_expiration)
+                    self.hold_expiration == other.hold_expiration and
+                    self.resources == other.resources)
         else:
             return False
 
@@ -595,6 +597,7 @@ class Node(BaseModel):
         d['connection_type'] = self.connection_type
         d['connection_port'] = self.connection_port
         d['hold_expiration'] = self.hold_expiration
+        d['resources'] = self.resources
         return d
 
     @staticmethod
@@ -644,6 +647,7 @@ class Node(BaseModel):
                 o.hold_expiration = 0
         else:
             o.hold_expiration = hold_expiration
+        o.resources = d.get('resources')
         return o