Restrict types to `APIGatewayProxyResultV2` or `APIGatewayProxyResult`

[John L. Armstrong IV]

Describe the bug

The TypeScript types indicate properties exist in Middy handlers that do not.

To Reproduce
How to reproduce the behaviour:

1. With a function url that uses the payload version format v2 with middy

Expected behaviour
If I specify APIGatewayProxyEventV2 and APIGatewayProxyResultV2 in export const middy = middyCore<APIGatewayProxyEventV2, APIGatewayProxyResultV2>(), then the handlers should only use the v2 types.

Environment (please complete the following information):

• Node.js: v20.11.0
• Middy: 5.2.4
• AWS SDK 2.1551.0

Additional context
The actual types include the old event formats

MiddyfiedHandler<APIGatewayProxyEventV2 & Omit<APIGatewayProxyEvent, "body"> & { body: JsonValue; } & APIGatewayProxyEvent & ... 4 more ... & { ...; }, APIGatewayProxyResultV2, Error, Context, {}>.handler: <unknown>(handler: MiddyInputHandler<APIGatewayProxyEventV2 & Omit<APIGatewayProxyEvent, "body"> & {
    body: JsonValue;
} & APIGatewayProxyEvent & ... 4 more ... & {
    ...;
}, APIGatewayProxyResultV2, Context>) => MiddyfiedHandler<...>

[Ben Szabo]

I'm running into some errors that are very similar to this, when using the http-router and it stems from using a middleware on the handlers, as the handler changes the types, rightly so, but the typing of the routes variable is unable to pick this up...

The code works, but I kinda have to ignore the typescript on that level.

Given the number of different middlewares, and their various outputs - this is not an easy thing to fix.

TS Playground example

[Naor Peled]

Hey @willfarrell,
should I take a look at this?

[will Farrell]

@naorpeled sure