Consider removal of warp::ext::set

[seanmonstar]

It takes advantage of warp's usage of thread-local storage, but that means we can't change away from internally using TLS as long as this function requires it.

[remexre]

What would the replacement API look like?

[seanmonstar]

I'm not certain. Perhaps by adding a way to turn a Filter into a Service, extensions could be set before reaching the filters. Or a new warp::ext::with_mut(impl Fn(&mut Extensions)) could be added.

[carllerche]

Makes sense 👍

[itsfarseen]

How to set an extension in latest version of warp?
I was trying to pass db pool to my routes.

[paulzhang5511]

@itsfarseen

fn with_db(pool: Pool) -> impl Filter<Extract = (Pool,), Error = Infallible> + Clone {
    warp::any().map(move || pool.clone())
}

let user_create = warp::path!("api" / "user" / "create")
        .and(warp::post())
        .and(warp::body::json())
        .and(with_db(pool.clone()))
        .and_then(user::user_create);