Count configured minimum and maximum numbers of instances

appengine/gce-backend/metrics.py

 # Copyright 2016 The LUCI Authors. All rights reserved.
 # Use of this source code is governed under the Apache License, Version 2.0
 # that can be found in the LICENSE file.
 
 """Metrics to track with ts_mon and event_mon."""
 
 import logging
 
 import gae_event_mon
 import gae_ts_mon
 
+import config
 import instance_group_managers
 
 
 # Overrides to create app-global metrics.
 GLOBAL_TARGET_FIELDS = {
   # Name of the module reporting the metric.
   'job_name': '',
   # Version of the app reporting the metric.
   'hostname': '',
   # ID of the instance reporting the metric.
   'task_num': 0,
 }
 
 
 GLOBAL_METRICS = {
+    'config_max_instances': gae_ts_mon.GaugeMetric(
+        'machine_provider/gce_backend/config/instances/max',
+        description='Maximum number of instances currently configured.',
+    ),
+    'config_min_instances': gae_ts_mon.GaugeMetric(
+        'machine_provider/gce_backend/config/instances/min',
+        description='Minimum number of instances currently configured.',
+    ),
     'instances': gae_ts_mon.GaugeMetric(
         'machine_provider/gce_backend/instances',
         description='Current count of the number of instances.',
     ),
 }
 
 
 config_valid = gae_ts_mon.BooleanMetric(
     'machine_provider/gce_backend/config/valid',
     description='Whether or not the current config is valid.',
 )
 
 
 def compute_global_metrics(): # pragma: no cover
+  for name, counts in config.count_instances().iteritems():
+    logging.info('%s min: %s', name, counts[0])
+    GLOBAL_METRICS['config_min_instances'].set(
+        counts[0],
+        fields={
+            'instance_template': name,
+        },
+        target_fields=GLOBAL_TARGET_FIELDS,
+    )
+    logging.info('%s max: %s', name, counts[1])
+    GLOBAL_METRICS['config_max_instances'].set(
+        counts[1],
+        fields={
+            'instance_template': name,
+        },
+        target_fields=GLOBAL_TARGET_FIELDS,
+    )
+
   for name, count in instance_group_managers.count_instances().iteritems():
     logging.info('%s: %s', name, count)
     GLOBAL_METRICS['instances'].set(
         count,
         fields={
             'instance_template': name,
         },
         target_fields=GLOBAL_TARGET_FIELDS,
     )
 
@@ skipping 10 matching lines @@
   Args:
     state: gae_event_mon.ChromeInfraEvent.GCEBackendMachineState.
     hostname: Name of the GCE instance this event is for.
   """
   state = gae_event_mon.MachineProviderEvent.GCEBackendMachineState.Value(state)
   event = gae_event_mon.Event('POINT')
   event.proto.event_source.host_name = hostname
   event.proto.machine_provider_event.gce_backend_state = state
   logging.info('Sending event: %s', event.proto)
   event.send()