Skip sending OTLP metrics request when payload is empty

[TrymBeast]

Hello,

I’m using OpenTelemetry (.NET) to export MassTransit metrics to Datadog via the OTLP exporter. When the metrics payload is empty, Datadog responds with HTTP 400.

Is there any configuration or recommended approach to prevent the exporter from sending a request when there’s nothing to export?

Environment details:

• OpenTelemetry .NET version: 1.9.0 (cannot upgrade currently due to dependency constraints)
• Exporter: OTLP HTTP/protobuf
• Target: Datadog OTLP metrics intake

One workaround I considered is using HttpClientFactory with a DelegatingHandler to short-circuit empty requests, but it would be great to have a native option in the exporter (e.g., SkipEmptyPayload = true or similar).

This would avoid unnecessary network calls and error logs in scenarios where metrics are sparse (e.g., MassTransit-only instrumentation).

Thanks!

[martincostello]

OpenTelemetry .NET version: 1.9.0 (cannot upgrade currently due to dependency constraints)

What are these constraints? v1.14.0 made various changes to the dependency tree that may have helped.

Realistically, if we did add a new option (or just automatically skip empty payloads), it would almost certainly only be available in a new version based on main, so you would still need to upgrade off v1.9.0 to benefit.

[TrymBeast]

Hello Martin, thank you for your answer.

The constraint is that the latest version of OpenTelemetry has dependencies to some Microsoft.Extensions packages on version 10 and unfortunately I'm still locked in version 8. We will upgrade to version 10 I just don't know when, but this would give it more urgency.

[Kielek]

It is no longer true, there is only one dependency from 10.0.0. It is System.Diagnostics.Diagnostics source.

Please check #6489

[TrymBeast]

Hello Kielek, in .NET 8 apps the latest version should work indeed as it depends on v8, but not on .net framework apps, I forgot to mention that.
The System.Diagnostics.Diagnostics version is not an issue to me, just the Microsoft.Extensions.Logging.Configuration and Microsoft.Extensions.Diagnostics.Abstractions.

[martincostello]

That's something you're going to have to work through to be able to upgrade then.

As I noted earlier, we can't add arbitrary new features to old versions. If we made changes for this specific ask, you'd still be blocked from using them unless you could upgrade to a new version with that change.

[TrymBeast]

I've talked internally and if you make this change we'll upgrade.