Support OTLP 1.x

[mx-psi]

Based on the submodule named 'proto' on the top-level folder of this repository, it looks like the OTLP proto definitions are based on open-telemetry/opentelemetry-proto@b43e9b1, i.e. v0.11.0 from October 2021. This means that the current generated datatypes (those in the 'otlp' folder) reference fields that no longer exist in more recent OTLP versions.

For example, I can find this reference to IntGauge:

hs-opentelemetry/otlp/src/Proto/Opentelemetry/Proto/Metrics/V1/Metrics.hs

Line 55 in 02653bb

IntGauge (),

which was removed in v0.12.0 (specifically on open-telemetry/opentelemetry-proto/pull/342).

OTLP has since released a stable version, and some OpenTelemetry components no longer support v0.11.0 (e.g. the OpenTelemetry Collector dropped support for OTLP v0.11.0 in v0.44.0). In order to make this library work with the rest of the OpenTelemetry ecosystem, it would be necessary to bump the proto definitions

[iand675]

Thanks for raising this!

[michaelpj]

Fixed in #150