Add support for Blazor WASM

[dbheale]

Hello!

I'm working on multiple Blazor WASM applications expecting to go live mid-year and I would love to use Honeycomb.oi as a collector. Unfortunately, there's no runtime pack for it.

Is this something that would be considered?

Thank you!

[cartermp]

Tentatively adding to our GA milestone for now. We'll need to look into if we need to add the right stuff only in this SDK distribution, or also/only in the upstream vendor-neutral SDK. Either way it shouldn't be a terribly large lift, just requires some investigation since Blazor WASM projects are a little special w.r.t. dependencies.

[cartermp]

FYI @dbheale this should work today - we're adding an example here: #251

[cartermp]

Plopping this link here: open-telemetry/opentelemetry-dotnet#2816

There are likely to be other issues with blazor-wasm even when an upstream fix lands and we take it. So while we should be able to make our SDK distro work with blazor-wasm, there may be further caveats.

[dbheale]

@cartermp Awesome, I'll check it out soon!

[cartermp]

Yeah, another quick update:

• It's possible to use this distro to write stuff to the console, but that's only because it uses a simple span processor (i.e., compute and export each span as it's created)
• It's not possible to configure a batch span processor since blazor is single-threaded. Which means the only way to use it would result in terrible performance for all but very simple apps
• Furthermore, there's quirks in actually calling the honeycomb API from the client. You'd need to configure a CORS policy.

All-in-all, I'd say Blazor WASM isn't quite ready as an application type for OpenTelemetry just yet. We did work on our end to ensure that you can indeed use our SDK distribution with a Blazor app, but these issues in Blazor are unavoidable for now.

If you're interested in setting up some more machinery, through the magic of JS Interop you can actually configure an app to send to honeycomb with this project: https://github.com/martinjt/otel-blazor-exporter

But this is the experimental realm, so we're likely to consider our SDK as GA without a good end-to-end experience for Blazor WASM.