Worker will swallow OOM exceptions

[paulbatum]

Description

Invocationhandler.InvokeAsync will catch any exception and never rethrows. This creates confusing hangs for terminal exceptions such as OutOfMemoryException where the desirable behavior is to crash the process.

azure-functions-dotnet-worker/src/DotNetWorker.Grpc/Handlers/InvocationHandler.cs

Lines 116 to 125 in 0f345be

	catch (Exception ex)
	{
	response.Result.Exception = _workerOptions.EnableUserCodeException ? ex.ToUserRpcException() : ex.ToRpcException();
	response.Result.Status = StatusResult.Types.Status.Failure;
	if (ex.InnerException is TaskCanceledException or OperationCanceledException)
	{
	response.Result.Status = StatusResult.Types.Status.Cancelled;
	}
	}

Steps to reproduce

The simplest repro is to explicitly throw out of memory with a function. The worker process will not crash.

        [Function(nameof(ThrowOutOfMemoryDirectly))]
        public IActionResult ThrowOutOfMemoryDirectly(
    [HttpTrigger(AuthorizationLevel.Anonymous, "get")] HttpRequest req)
        {
            throw new OutOfMemoryException();
        }

You can also reproduce with a more realistic setup of running the worker in a constrained memory environment and allocating above that limit, but this will introduce other variables, such as whether the kernel chooses to kill the process due to being out of memory.