[Metricbeat] When Logstash module is enable and we fail to reach it, metricbeat refuses to starts

[ph]

Looking at the code of the Logstash module I believe the module is also affected by a similar bug defined in #15258 for Kibana. I also looked at the Elasticsearch module but I think this one is OK.

beats/metricbeat/module/logstash/node/node.go

Lines 55 to 81 in d545f69

	func New(base mb.BaseMetricSet) (mb.MetricSet, error) {
	ms, err := logstash.NewMetricSet(base)
	if err != nil {
	return nil, err
	}
	if ms.XPack {
	logstashVersion, err := logstash.GetVersion(ms)
	if err != nil {
	return nil, err
	}
	arePipelineGraphAPIsAvailable := logstash.ArePipelineGraphAPIsAvailable(logstashVersion)
	if err != nil {
	return nil, err
	}
	if !arePipelineGraphAPIsAvailable {
	const errorMsg = "The %v metricset with X-Pack enabled is only supported with Logstash >= %v. You are currently running Logstash %v"
	return nil, fmt.Errorf(errorMsg, ms.FullyQualifiedName(), logstash.PipelineGraphAPIsAvailableVersion, logstashVersion)
	}
	}
	return &MetricSet{
	ms,
	}, nil
	}

[ph]

@ycombinator could you take a look?

[ph]

I haven't checked the beat modules, so we might want to double-check it to make sure the module is not affected by a similar bug.

[ycombinator]

I checked the beat module, and it is okay. It's not making any HTTP calls in its metricsets' New functions.

[radoondas]

Hey @ycombinator & @ph, I am a bit confused if this one is bug which we will fix or this is not a bug for Logstash output in the end. Can you please clarify? Thanks!

[ph]

@radoondas It's a bug, but it's not related tot he Logstash output but to Metricbeat's Logstash module, the module that query the Logstash API to collect metrics and send them to Elasticsearch.