Jack Berg

Related [spec issue](https://github.com/open-telemetry/opentelemetry-specification/issues/2497).

> GlobalOpenTelemetry.get has a side effect of setting the noop telemetry causing exception above. If it didn't have this side effect then an application might be started with libraries containing...

Are array tags actually supported in zipkin's data model? I get a 400 Bad request when I try to send up a payload with them. For example, the following with...

The [dotnet](https://github.com/open-telemetry/opentelemetry-dotnet/blob/main/src/OpenTelemetry.Exporter.Zipkin/Implementation/ZipkinSpan.cs#L215-L218) implementation appears to just comma separate the values, rather than a JSON list string. The [js](https://github.com/open-telemetry/opentelemetry-js/blob/main/packages/opentelemetry-exporter-zipkin/src/transform.ts#L79) implementation does the same as dotnot. (`String(['foo', 'bar']) => 'foo,bar'`) The [go](https://github.com/open-telemetry/opentelemetry-go/blob/ec26b556da5c3a71779f40ce8e99e85830e73747/exporters/zipkin/model.go#L184-L196)...

> So, it sounds like .net and java are currently in alignment, then? Yes.

> I noticed this problem too, is this going to get merged? Do you have a repo or some logs you can share? As mentioned [here](https://github.com/open-telemetry/opentelemetry-java-contrib/pull/253#discussion_r853429001), if I understand correctly,...

They aren't guaranteed to be identical objects (although those logs appear to indicate they are identical 🤔), but they are guaranteed to aggregate and export to the same metric.

If I understand correctly this should be resolved with [#4222](https://github.com/open-telemetry/opentelemetry-java/pull/4222). At this point: - Async instruments can have multiple callbacks associated with them. - You can request the same instrument...

> asynchronous/delta: in this case, it is safe to stop reporting the instrument/attribute pair, but restarting the same instrument/attribute pair is complicated for the same reason as synchronous/cumulative. In the...

The java SDK data model and its OTLP metric exporters do support summaries. This means that you can implement the [MetricData](https://github.com/open-telemetry/opentelemetry-java/blob/main/sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/data/MetricData.java#L64) interface with a type of [MetricDataType.SUMMARY](https://github.com/open-telemetry/opentelemetry-java/blob/main/sdk/metrics/src/main/java/io/opentelemetry/sdk/metrics/data/MetricDataType.java#L29-L34). And you can...