ignore compute.instance.create.start for metrics

do not build metrics off compute.instance.create.start as it
doesn't have enough information in it to push to Gnocchi. there is
an .end event that happens seconds later so .start event has little
value outside context of event.

we change fnmatch to regex for more useful regex comparison and it's
faster

not a complete fix as compute.instance.update also is missing host
value occasionally

Partial-Bug: #1718290
Change-Id: I2aa7045873fd740255a3be5f64b9e9f5fd94e2d4

ceilometer/data/meters.d/meters.yaml

@@ -101,7 +101,7 @@ metric:
     lookup: ['name', 'unit', 'volume']
 
   - name: 'memory'
-    event_type: 'compute.instance.*'
+    event_type: &instance_events compute.instance.(?!create.start).*
     type: 'gauge'
     unit: 'MB'
     volume: $.payload.memory_mb
@@ -118,7 +118,7 @@ metric:
       image_ref: $.payload.image_meta.base_image_ref
 
   - name: 'vcpus'
-    event_type: 'compute.instance.*'
+    event_type: *instance_events
     type: 'gauge'
     unit: 'vcpu'
     volume: $.payload.vcpus
@@ -143,7 +143,7 @@ metric:
       <<: *instance_meta
 
   - name: 'disk.root.size'
-    event_type: 'compute.instance.*'
+    event_type: *instance_events
     type: 'gauge'
     unit: 'GB'
     volume: $.payload.root_gb
@@ -155,7 +155,7 @@ metric:
        <<: *instance_meta
 
   - name: 'disk.ephemeral.size'
-    event_type: 'compute.instance.*'
+    event_type: *instance_events
     type: 'gauge'
     unit: 'GB'
     volume: $.payload.ephemeral_gb

ceilometer/meter/notifications.py

@@ -13,13 +13,13 @@
 import glob
 import itertools
 import os
+import re
 
 import pkg_resources
 import six
 
 from oslo_config import cfg
 from oslo_log import log
-from oslo_utils import fnmatch
 from stevedore import extension
 
 from ceilometer import declarative
@@ -72,6 +72,7 @@ class MeterDefinition(object):
         self._event_type = self.cfg.get('event_type')
         if isinstance(self._event_type, six.string_types):
             self._event_type = [self._event_type]
+        self._event_type = [re.compile(etype) for etype in self._event_type]
 
         if ('type' not in self.cfg.get('lookup', []) and
                 self.cfg['type'] not in sample_util.TYPES):
@@ -107,7 +108,7 @@ class MeterDefinition(object):
 
     def match_type(self, meter_name):
         for t in self._event_type:
-            if fnmatch.fnmatch(meter_name, t):
+            if t.match(meter_name):
                 return True
 
     def to_samples(self, message, all_values=False):