Need clarification of docs/instrumenting/exposition_formats.md, is it missing information?

[fieldju]

# HELP foo_total  
# TYPE foo_total counter
foo_total{hostname="localhost",optionalExtraMetadata="my-cool-value",} 1.0
# HELP foo_total  
# TYPE foo_total counter
foo_total{hostname="localhost",} 1.0

:point_up: is this valid as of v0.4.0? I wrote an integration test that proves it is, but there is some debate on whether that's to spec or not.

Reading through https://github.com/prometheus/docs/blob/master/content/docs/instrumenting/exposition_formats.md

I am not seeing any reference to

A given metric name MAY NOT repeat if the cardinality of the label-value pairs between its instances varies.

From this section

of the legacy Client Data Exposition Format document.

Does this mean as of the current spec you can have the same metric more than once with varying labels?

Would be nice to add this info to the current doc.

[brian-brazil]

This is not valid exposition, as you're repeating the HELP/TYPE and will be rejected by the reference parser in https://github.com/prometheus/common/tree/master/expfmt

Per the doc "Only one TYPE line may exist for a given metric name. ", and similarly for HELP.