Merge branch 'release-v0.37' into backport-5704-to-release-v0.37

CHANGELOG.md

@@ -7,6 +7,19 @@ This document contains a historical list of changes between releases. Only
 changes that impact end-user behavior are listed; changes to documentation or
 internal API changes are not present.
 
+v0.37.4 (2023-11-06)
+-----------------
+
+### Enhancements
+
+- Added an `add_metric_suffixes` option to `otelcol.exporter.prometheus` in flow mode,
+  which configures whether to add type and unit suffixes to metrics names. (@mar4uk)
+
+### Bugfixes
+
+- Fix a bug where reloading the configuration of a `loki.write` component lead
+  to a panic. (@tpaschalis)
+
 v0.37.3 (2023-10-26)
 -----------------
 
@@ -30,7 +43,7 @@ v0.37.3 (2023-10-26)
   - `otelcol.receiver.kafka` has a new `header_extraction` block to extract headers from Kafka records.
   - `otelcol.receiver.kafka` has a new `version` argument to change the version of 
     the SASL Protocol for SASL authentication.
-  
+
 v0.37.2 (2023-10-16)
 -----------------
 

component/common/loki/wal/watcher_metrics.go

@@ -70,13 +70,23 @@ func NewWatcherMetrics(reg prometheus.Registerer) *WatcherMetrics {
 	}
 
 	if reg != nil {
-		reg.MustRegister(m.recordsRead)
-		reg.MustRegister(m.recordDecodeFails)
-		reg.MustRegister(m.droppedWriteNotifications)
-		reg.MustRegister(m.segmentRead)
-		reg.MustRegister(m.currentSegment)
-		reg.MustRegister(m.watchersRunning)
+		m.recordsRead = mustRegisterOrGet(reg, m.recordsRead).(*prometheus.CounterVec)
+		m.recordDecodeFails = mustRegisterOrGet(reg, m.recordDecodeFails).(*prometheus.CounterVec)
+		m.droppedWriteNotifications = mustRegisterOrGet(reg, m.droppedWriteNotifications).(*prometheus.CounterVec)
+		m.segmentRead = mustRegisterOrGet(reg, m.segmentRead).(*prometheus.CounterVec)
+		m.currentSegment = mustRegisterOrGet(reg, m.currentSegment).(*prometheus.GaugeVec)
+		m.watchersRunning = mustRegisterOrGet(reg, m.watchersRunning).(*prometheus.GaugeVec)
 	}
 
 	return m
 }
+
+func mustRegisterOrGet(reg prometheus.Registerer, c prometheus.Collector) prometheus.Collector {
+	if err := reg.Register(c); err != nil {
+		if are, ok := err.(prometheus.AlreadyRegisteredError); ok {
+			return are.ExistingCollector
+		}
+		panic(err)
+	}
+	return c
+}

component/otelcol/exporter/prometheus/internal/convert/convert.go

@@ -63,6 +63,8 @@ type Options struct {
 	// IncludeScopeLabels includes the otel_scope_name and otel_scope_version
 	// labels from the scope in the metrics.
 	IncludeScopeLabels bool
+	// AddMetricSuffixes controls whether suffixes are added to metric names. Defaults to true.
+	AddMetricSuffixes bool
 }
 
 var _ consumer.Metrics = (*Converter)(nil)
@@ -286,8 +288,7 @@ func (conv *Converter) consumeMetric(app storage.Appender, memResource *memorySe
 }
 
 func (conv *Converter) consumeGauge(app storage.Appender, memResource *memorySeries, memScope *memorySeries, m pmetric.Metric) {
-	// TODO: should we make the param addMetricSuffixes configurable? For now we set the default value (true) to keep the same behavior as before
-	metricName := prometheus.BuildCompliantName(m, "", true)
+	metricName := prometheus.BuildCompliantName(m, "", conv.opts.AddMetricSuffixes)
 
 	metricMD := conv.createOrUpdateMetadata(metricName, metadata.Metadata{
 		Type: textparse.MetricTypeGauge,
@@ -389,7 +390,7 @@ func getNumberDataPointValue(dp pmetric.NumberDataPoint) float64 {
 }
 
 func (conv *Converter) consumeSum(app storage.Appender, memResource *memorySeries, memScope *memorySeries, m pmetric.Metric) {
-	metricName := prometheus.BuildCompliantName(m, "", true)
+	metricName := prometheus.BuildCompliantName(m, "", conv.opts.AddMetricSuffixes)
 
 	// Excerpt from the spec:
 	//
@@ -447,7 +448,7 @@ func (conv *Converter) consumeSum(app storage.Appender, memResource *memorySerie
 }
 
 func (conv *Converter) consumeHistogram(app storage.Appender, memResource *memorySeries, memScope *memorySeries, m pmetric.Metric) {
-	metricName := prometheus.BuildCompliantName(m, "", true)
+	metricName := prometheus.BuildCompliantName(m, "", conv.opts.AddMetricSuffixes)
 
 	if m.Histogram().AggregationTemporality() != pmetric.AggregationTemporalityCumulative {
 		// Drop non-cumulative histograms for now, which is permitted by the spec.
@@ -606,7 +607,7 @@ func (conv *Converter) convertExemplar(otelExemplar pmetric.Exemplar, ts time.Ti
 }
 
 func (conv *Converter) consumeSummary(app storage.Appender, memResource *memorySeries, memScope *memorySeries, m pmetric.Metric) {
-	metricName := prometheus.BuildCompliantName(m, "", true)
+	metricName := prometheus.BuildCompliantName(m, "", conv.opts.AddMetricSuffixes)
 
 	metricMD := conv.createOrUpdateMetadata(metricName, metadata.Metadata{
 		Type: textparse.MetricTypeSummary,