Hey @daylikon,

k6 supports custom metrics: https://grafana.com/docs/k6/latest/using-k6/metrics/create-custom-metrics/
And with custom metrics, you can also have tags, like this counter metric example: https://grafana.com/docs/k6/latest/javascript-api/k6-metrics/counter/

Yes, I can use k6 custom metrics, but I want to use xk6-kafka metric value (kafka_writer_write_seconds/kafka_reader_read_seconds/etc).

Right now writer returns undefined, the difference between the time calculated between writer.produce() is very different from the metric.

Is there a way to get plugin metrics after sending or reading a message, so that they can then be used in custom metrics?

@daylikon

I don't think so, unless you export them while the test is running.

@mostafa

So I’m thinking about how to export metrics while the test is running. Messages are written in the same topic, but the “name” is different.

Now in the csv and given output plugin, if take the kafka_writer_write_seconds metric, I can compare by topic, but since the payload of the messages is different, I want to aggregate these messages by “name,” but now it’s impossible to do that.

@daylikon

Currently only static tags are added to reader and writer metrics based on the metrics provided from the kafka-go module's readerStats and writerStats. You can modify the xk6-kafka's reportReaderStats and reportWriterStats functions to include dynamic tags and try to see if it works the way you expect.

@daylikon

Ref: #272 (comment)