Handling missing counters in application_pool metricset

CHANGELOG.next.asciidoc

@@ -341,6 +341,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d
 - Update fields.yml in the azure module, missing metrics field. {pull}20918[20918]
 - The `elasticsearch/index` metricset only requests wildcard expansion for hidden indices if the monitored Elasticsearch cluster supports it. {pull}20938[20938]
 - Disable Kafka metricsets based on Jolokia by default. They require a different configuration. {pull}20989[20989]
+- Handle missing counters in the application_pool metricset. {pull}21071[21071]
 
 *Packetbeat*
 

x-pack/metricbeat/module/iis/application_pool/application_pool.go

@@ -84,7 +84,6 @@ func (m *MetricSet) Fetch(report mb.ReporterV2) error {
  break
  }
  }
-
  return nil
 }
 

x-pack/metricbeat/module/iis/application_pool/reader.go

@@ -101,10 +101,10 @@ func (r *Reader) initAppPools() error {
  if err == pdh.PDH_CSTATUS_NO_COUNTER || err == pdh.PDH_CSTATUS_NO_COUNTERNAME || err == pdh.PDH_CSTATUS_NO_INSTANCE || err == pdh.PDH_CSTATUS_NO_OBJECT {
  r.log.Infow("Ignoring non existent counter", "error", err,
  logp.Namespace("application pool"), "query", value)
- continue
  } else {
- return errors.Wrapf(err, `failed to expand counter (query="%v")`, value)
+ r.log.Error(err, `failed to expand counter path (query= "%v")`, value)
  }
+ continue
  }
  newQueries = append(newQueries, childQueries...)
  // check if the pdhexpandcounterpath/pdhexpandwildcardpath functions have expanded the counter successfully.