Fix prometheus exporter error log for unknown metric type

[pavolloffay]

Description

Link to tracking issue

Fixes the data_type field not being properly formatted

{
  "level": "error",
  "ts": "2025-10-16T10:26:48.992Z",
  "caller": "[email protected]/accumulator.go:97",
  "msg": "failed to translate metric",
  "resource": {
    "service.instance.id": "c2ca81b8-ce73-473d-b897-6b946935260f",
    "service.name": "otelcol-contrib",
    "service.version": "0.137.0"
  },
  "otelcol.component.id": "prometheus",
  "otelcol.component.kind": "exporter",
  "otelcol.signal": "metrics",
  "data_type": "\u0004",
  "metric_name": "prometheus_http_request_duration_seconds",
  "stacktrace": "github.com/open-telemetry/opentelemetry-collector-contrib/exporter/prometheusexporter.(*lastValueAccumulator).addMetric\n\tgithub.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/accumulator.go:97\ngithub.com/open-telemetry/opentelemetry-collector-contrib/exporter/prometheusexporter.(*lastValueAccumulator).Accumulate\n\tgithub.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/accumulator.go:74\ngithub.com/open-telemetry/opentelemetry-collector-contrib/exporter/prometheusexporter.(*collector).processMetrics\n\tgithub.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/collector.go:171\ngithub.com/open-telemetry/opentelemetry-collector-contrib/exporter/prometheusexporter.(*prometheusExporter).ConsumeMetrics\n\tgithub.com/open-telemetry/opentelemetry-collector-contrib/exporter/[email protected]/prometheus.go:93\ngo.opentelemetry.io/collector/consumer.ConsumeMetricsFunc.ConsumeMetrics\n\tgo.opentelemetry.io/collector/[email protected]/metrics.go:27\ngo.opentelemetry.io/collector/exporter/exporterhelper.NewMetrics.RequestConsumeFromMetrics.func2\n\tgo.opentelemetry.io/collector/exporter/[email protected]/internal/queuebatch/metrics.go:134\ngo.opentelemetry.io/collector/exporter/exporterhelper/internal/sender.(*sender[...]).Send\n\tgo.opentelemetry.io/collector/exporter/[email protected]/internal/sender/sender.go:31\ngo.opentelemetry.io/collector/exporter/exporterhelper/internal.(*timeoutSender[...]).Send\n\tgo.opentelemetry.io/collector/exporter/[email protected]/internal/timeout_sender.go:54\ngo.opentelemetry.io/collector/exporter/exporterhelper/internal.(*obsReportSender[...]).Send\n\tgo.opentelemetry.io/collector/exporter/[email protected]/internal/obs_report_sender.go:92\ngo.opentelemetry.io/collector/exporter/exporterhelper/internal.(*BaseExporter).Send\n\tgo.opentelemetry.io/collector/exporter/[email protected]/internal/base_exporter.go:112\ngo.opentelemetry.io/collector/exporter/exporterhelper/internal.NewMetricsRequest.newConsumeMetrics.func1\n\tgo.opentelemetry.io/collector/exporter/[email protected]/internal/new_request.go:176\ngo.opentelemetry.io/collector/consumer.ConsumeMetricsFunc.ConsumeMetrics\n\tgo.opentelemetry.io/collector/[email protected]/metrics.go:27\ngo.opentelemetry.io/collector/service/internal/refconsumer.refMetrics.ConsumeMetrics\n\tgo.opentelemetry.io/collector/[email protected]/internal/refconsumer/metrics.go:29\ngo.opentelemetry.io/collector/internal/fanoutconsumer.(*metricsConsumer).ConsumeMetrics\n\tgo.opentelemetry.io/collector/internal/[email protected]/metrics.go:62\ngo.opentelemetry.io/collector/processor/processorhelper.NewMetrics.func1\n\tgo.opentelemetry.io/collector/processor/[email protected]/metrics.go:71\ngo.opentelemetry.io/collector/consumer.ConsumeMetricsFunc.ConsumeMetrics\n\tgo.opentelemetry.io/collector/[email protected]/metrics.go:27\ngo.opentelemetry.io/collector/service/internal/refconsumer.refMetrics.ConsumeMetrics\n\tgo.opentelemetry.io/collector/[email protected]/internal/refconsumer/metrics.go:29\ngo.opentelemetry.io/collector/consumer.ConsumeMetricsFunc.ConsumeMetrics\n\tgo.opentelemetry.io/collector/[email protected]/metrics.go:27\ngithub.com/open-telemetry/opentelemetry-collector-contrib/receiver/prometheusremotewritereceiver.(*prometheusRemoteWriteReceiver).handlePRW\n\tgithub.com/open-telemetry/opentelemetry-collector-contrib/receiver/[email protected]/receiver.go:198\nnet/http.HandlerFunc.ServeHTTP\n\tnet/http/server.go:2322\nnet/http.(*ServeMux).ServeHTTP\n\tnet/http/server.go:2861\ngo.opentelemetry.io/collector/config/confighttp.(*decompressor).ServeHTTP\n\tgo.opentelemetry.io/collector/config/[email protected]/compression.go:272\ngo.opentelemetry.io/collector/config/confighttp.(*ServerConfig).ToServer.maxRequestBodySizeInterceptor.func2\n\tgo.opentelemetry.io/collector/config/[email protected]/server.go:350\nnet/http.HandlerFunc.ServeHTTP\n\tnet/http/server.go:2322\ngo.opentelemetry.io/contrib/instrumentation/net/http/otelhttp.(*middleware).serveHTTP\n\tgo.opentelemetry.io/contrib/instrumentation/net/http/[email protected]/handler.go:180\ngo.opentelemetry.io/contrib/instrumentation/net/http/otelhttp.NewMiddleware.func1.1\n\tgo.opentelemetry.io/contrib/instrumentation/net/http/[email protected]/handler.go:67\nnet/http.HandlerFunc.ServeHTTP\n\tnet/http/server.go:2322\ngo.opentelemetry.io/collector/config/confighttp.(*clientInfoHandler).ServeHTTP\n\tgo.opentelemetry.io/collector/config/[email protected]/clientinfohandler.go:26\nnet/http.serverHandler.ServeHTTP\n\tnet/http/server.go:3340\nnet/http.(*conn).serve\n\tnet/http/server.go:2109"
}

Testing

Documentation