actix-website/examples/middleware/src/user_sessions.rs

// <user-session>
use actix_session::{CookieSession, Session};
use actix_web::{web, App, Error, HttpResponse, HttpServer};

pub fn index(session: Session) -> Result<HttpResponse, Error> {
    // access session data
    if let Some(count) = session.get::<i32>("counter")? {
        session.set("counter", count + 1)?;
    } else {
        session.set("counter", 1)?;
    }

    Ok(HttpResponse::Ok().body(format!(
        "Count is {:?}!",
        session.get::<i32>("counter")?.unwrap()
    )))
}

pub fn main() {
    HttpServer::new(|| {
        App::new()
            .wrap(
                CookieSession::signed(&[0; 32]) // <- create cookie based session middleware
                    .secure(false),
            )
            .service(web::resource("/").to(index))
    })
    .bind("127.0.0.1:8088")
    .unwrap()
    .run()
    .unwrap();
}
// </user-session>