Autoinstrument Java lambda RequestStreamHandler, not just RequestHandler

[hertzsprung]

Is your feature request related to a problem? Please describe.

Yes. Using the Java agent lambda layer, metrics and traces from a RequestStreamHandler are not flushed promptly when the lambda function completes. This only affects RequestStreamHandlers; RequestHandlers behave correctly.

Describe the solution you'd like

Autoinstrument both types of request handler

Describe alternatives you've considered

A separate wrapper is available to support RequestStreamHandlers, but this isn't available from any publicly published lambda layer, as far as I can tell.

Additional context

No response

[trask]

cc @tylerbenson @rapphil

[tylerbenson]

On the lambda sig side, I'd be open to publishing a layer with the wrappers (and a collector) separate from the javaagent layer. I didn't put time into it initially because I didn't know how widely used the wrappers were. Would that solve your problem?

@hertzsprung If you want to attempt submitting your own PR for adding auto instrumentation for RequestStreamHandler, that sounds like a potential good first contribution as you can lean heavily on the other instrumentation for inspiration.

[hertzsprung]

I've only read the wrapper docs and not tried it but I could look at using the wrapper layer instead of the agent layer.