feat: Easy Event Deserialization

[jeromevdl]

Issue #, if available:

Description of changes:

New feature in the serialization module: ability to easily extract the content from an Event (many built-in events).

Ex with API Gateway:

import static software.amazon.lambda.powertools.utilities.EventDeserializer.from;

public class AppParams implements RequestHandler<APIGatewayProxyRequestEvent, APIGatewayProxyResponseEvent> {
    public APIGatewayProxyResponseEvent handleRequest(APIGatewayProxyRequestEvent event, Context context) {
        // will automatically extract the content from the body and serialize it as an Order
        Order order = extractDataFrom(event).as(Order.class); 

        // ...
    }
}

Ex with SQS:

import static software.amazon.lambda.powertools.utilities.EventDeserializer.from;

public class AppParams implements RequestHandler<SQSEvent, String> {
    public String handleRequest(SQSEvent event, Context context) {
        // will automatically extract the content from records body, serialize them as Order, and return a list
        List<Order> orders = extractDataFrom(event).asListOf(Order.class); 

        // ...
    }
}

Checklist

• Meet tenets criteria
• Update tests
• Update docs ==> will update the doc once the code is reviewed & accepted
• PR title follows conventional commit semantics

Breaking change checklist

RFC issue #:

• Migration process documented
• Implement warnings (if it can live side by side)

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[pankajagrawal16]

Some suggestions.

[pankajagrawal16]

What mechanisms can be have to update these when java lib introduces new event type?

[pankajagrawal16]

I am thinking may be we can have a github action which somehow polls java lib weekly or daily or whatever and create an issue if for powertools if something new is added for events ?

[jeromevdl]

Not all events make sense in here. I didn't add all, only those where there is a message or something meaningful to extract. Maybe I forgot some interesting ones.

[msailes]

We can get an email on each release of the library. Dependabot will also raise a PR.

[pankajagrawal16]

Ok, may be i am overthinking this, we wait for doing anything more until we see it being a problem

[msailes]

Would anything change post v4 of the events library?

It might be worth a quick chat with @andclt.

[msailes]

In v4 of the events lib, there will be a dependency on Jackson, I don't think that changes anything, just worth noting.

[pankajagrawal16]

Minor suggestion, from code perspective, it looks good to me, so if you want to start documenting it.

[jeromevdl]

@pankajagrawal16 @msailes ready for further review / merge

[msailes]

👍🏻

[pankajagrawal16]

Looks good. Just one minor suggestion on docs.

[pankajagrawal16]

Great 🎉 ... cc @kozub