Prometheus surfacer outputs incorrect TYPE line in histogram

[ykawamot]

In prometheus docs,
https://prometheus.io/docs/instrumenting/exposition_formats/#histograms-and-summaries
histogram type has a TYPE line for x and three metrics x_sum, x_count and x_bucket.
However, prometheus surfacer outputs a TYPE line for each metrics.

My configuration:

probe {
  name: "http-probe-test"
  type: HTTP
  targets {
    host_names: "example.com"
  }

  latency_unit: "ms"
  latency_distribution {
    explicit_buckets: "10,100,1000"
  }
}

Expected:

#TYPE latency histogram
latency_sum{ptype="http",probe="http-probe-test",dst="example.com"} 45896.18931099989 1581510329070
latency_count{ptype="http",probe="http-probe-test",dst="example.com"} 4644 1581510329070
latency_bucket{ptype="http",probe="http-probe-test",dst="example.com",le="10"} 4598 1581510329070
latency_bucket{ptype="http",probe="http-probe-test",dst="example.com",le="100"} 4644 1581510329070
latency_bucket{ptype="http",probe="http-probe-test",dst="example.com",le="1000"} 4644 1581510329070
latency_bucket{ptype="http",probe="http-probe-test",dst="example.com",le="+Inf"} 4644 1581510329070

Actual:

#TYPE latency_sum histogram
latency_sum{ptype="http",probe="http-probe-test",dst="example.com"} 45896.18931099989 1581510329070
#TYPE latency_count histogram
latency_count{ptype="http",probe="http-probe-test",dst="example.com"} 4644 1581510329070
#TYPE latency_bucket histogram
latency_bucket{ptype="http",probe="http-probe-test",dst="example.com",le="10"} 4598 1581510329070
latency_bucket{ptype="http",probe="http-probe-test",dst="example.com",le="100"} 4644 1581510329070
latency_bucket{ptype="http",probe="http-probe-test",dst="example.com",le="1000"} 4644 1581510329070
latency_bucket{ptype="http",probe="http-probe-test",dst="example.com",le="+Inf"} 4644 1581510329070

[manugarg]

@ykawamot Thanks a lot for reporting this. This indeed looks like a bug. I'll try to submit a fix soon.

[manugarg]

9a0f182 fixes it. New release is due next week.

[ykawamot]

Thank you, I confirmed that is working correctly.