Add support for Async RequestHandler about aws-lambda-java-libs HOT 7 CLOSED

Could you give an example of how this would be used?

Would you want the Lambda function to return early while work happens in the background?

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Closing awaiting more information.

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Would you want the Lambda function to return early while work happens in the background?

The point is to avoid blocking a thread when responding to a request.
I've detailed out the motivation in an MS painting:

Kindly reopen this issue, async programming is a feature so basic it's integrated into all modern languages (Javascript, C#, Dart, Swift, Python, Ruby async, Go chan, Kotlin suspend)
Any method that expects to do IO work should be defined as async/suspend e.g.
Kotlin:

suspend fun handleRequest(request: Request): Response {
}

Java:

public Future<Response> handleRequest(Request request) {
}

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Each execution environment of a Lambda function only handles one request at once.

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What does that mean? If two requests need to be met at the same time it starts 2 separate processes?
In NodeJs it documenately doesn't work that way:

Node.js initialization
Node.js has a unique event loop model that causes its initialization behavior to be different from other runtimes. Specifically, Node.js uses a non-blocking I/O model that supports asynchronous operations. This model allows Node.js to perform efficiently for most workloads. For example, if a Node.js function makes a network call, that request may be designated as an asynchronous operation and placed into a callback queue. The function may continue to process other operations within the main call stack without getting blocked by waiting for the network call to return. Once the network call is returned, its callback is executed and then removed from the callback queue.
Some initialization tasks may run asynchronously. These asynchronous tasks are not guaranteed to complete execution prior to an invocation. For example, code that makes a network call to fetch a parameter from AWS Parameter Store may not be complete by the time Lambda executes the handler function. As a result, the variable may be null during an invocation. To avoid this, ensure that variables and other asynchronous code are fully initialized before continuing with the rest of the function’s core business logic.

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If a second invoke of a Lambda function is made before the first has finished a new execution environment will be created.

https://docs.aws.amazon.com/lambda/latest/dg/lambda-runtime-environment.html

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I see. As I don't see this model changing, there's no point for an EventHandler to be async.

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