传递一个actix_web::dev::ServiceRequest参数并从.cookie获取cookie应该读取cookie数据：

use actix_web::{dev, web, HttpResponse};
use futures::future::{ok, Ready};

async fn auth_middleware(req: dev::ServiceRequest, srv: web::Data<actix_web::AppState>) -> Result<dev::ServiceResponse, actix_web::Error> {
    let cookie_value = req
        .cookie("name-of-cookie")
        .map(|cookie| cookie.value().to_owned())
        .ok_or_else(|| HttpResponse::Unauthorized().finish())?;

    if !is_authorized(&cookie_value) {
        return Err(HttpResponse::Unauthorized().finish().into());
    }

    // authorized ? continue to the next middleware/handler
    let fut = srv
        .get_ref()
        .clone()
        .call(req)
        .await
        .map_err(|e| HttpResponse::InternalServerError().body(e.to_string()))?;
    Ok(fut)
}

fn is_authorized(cookie_value: &str) -> bool {
    // Authorization logic here
    true
}

let app = App::new()
    .data(AppState {})
    .wrap_fn(auth_middleware) 
    .service(/* actix-web services */);