VictoriaMetrics/VictoriaMetrics · error

cannot unmarshal DataDog %s request with size %d bytes: %w

Error message

cannot unmarshal DataDog %s request with size %d bytes: %w

What it means

Returned by the DataDog v2 streamparser's parseData when the request body (identified as contentType, either application/x-protobuf or JSON) cannot be unmarshaled into datadogv2.Request — it wraps the UnmarshalProtobuf/UnmarshalJSON error. %d is the body size in bytes.

Source

Thrown at lib/protoparser/datadogv2/stream/streamparser.go:43

		return fmt.Errorf("cannot decode DataDog protocol data: %w", err)
	}
	return nil
}

func parseData(data []byte, contentType string, callback func(series []datadogv2.Series) error) error {
	req := getRequest()
	defer putRequest(req)

	var err error
	switch contentType {
	case "application/x-protobuf":
		err = datadogv2.UnmarshalProtobuf(req, data)
	default:
		err = datadogv2.UnmarshalJSON(req, data)
	}
	if err != nil {
		unmarshalErrors.Inc()
		return fmt.Errorf("cannot unmarshal DataDog %s request with size %d bytes: %w", contentType, len(data), err)
	}

	rows := 0
	series := req.Series
	for i := range series {
		rows += len(series[i].Points)
		if *datadogutil.SanitizeMetricName {
			series[i].Metric = datadogutil.SanitizeName(series[i].Metric)
		}
	}
	rowsRead.Add(rows)

	if err := callback(series); err != nil {
		return fmt.Errorf("error when processing imported data: %w", err)
	}
	return nil
}

View on GitHub (pinned to 5079fb58f1)

Solutions

1. Match Content-Type to the body: application/json or application/x-protobuf
2. Fix the payload per the DataDog v2 series schema

When it happens

Trigger: Thrown at lib/protoparser/datadogv2/stream/streamparser.go:43 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of VictoriaMetrics/VictoriaMetrics@5079fb58f1 (2026-09-03). Data as JSON: /api/errors/e309f8c974a37ea0. Report an issue: GitHub.