SOme Error : i was trying to learn rust by "returns a reference to a captured variable which escapes the closure body"

i am learning from this pdf book "hands-on microservices with rust: build, test, and deploy scalable and reactive microservices with rust 2018"

Code doesn't work so I use google to do some search and I am in problem.
if you find any learning guide of rust by example please share it.
this Book I little older and codes does not work with new rust versions.

use hyper::server::conn::AddrStream;
use hyper::service::{make_service_fn, service_fn};
use hyper::{Body, Request, Response, Server, StatusCode};
use std::convert::Infallible;
use std::net::SocketAddr;
use std::sync::{Arc, Mutex};
use slab::Slab;
use hyper::http::Method;
// use serde_json;

const INDEX: &'static str = r#"
<h1>Hi\n</h1>
<p>I love this\n</p>
"#;

type UserId = u64;
#[derive(Debug, Copy, Clone)]
struct UserData;


type UserDb = Arc<Mutex<UserData>>;
type UserDb12 = Arc<Mutex<i32>>;
const USER_PATH: &str = "/user/";

async fn handle(
    context: AppContext,
    addr: SocketAddr,
    req: Request<Body>,
    user_db: &UserDb,
) -> Result<Response<Body>, Infallible> {

    // println!("{:?}", serde_json::from_slice(req.body()));

    // let body = req.body().concat2().wait().unwrap().into_bytes();
    // let s = serde_json::from_slice(&body).unwrap();
    // println!("{:?}",s);
    println!("{:?}", req);


    match (req.method(), req.uri().path()) {
        (&Method::GET, "/") => {
            // Ok(INDEX.into())
            Ok(Response::new(Body::from("<h1>this is rust 4.0</h1>")))
        },
        (&Method::GET, "/love") => {
            // Ok(INDEX.into())
            Ok(Response::new(Body::from("Why do i love you.?")))
        },
        (&Method::GET, "/index") => {
            // Ok(INDEX.into())
            Ok(Response::new(Body::from(INDEX)))
        },
        (method, path) if path.starts_with(USER_PATH) => {
            println!("Unimplemented");
            // Ok(Response::new(Body::from("Not implementd")))
            let user_id = path.trim_start_matches(USER_PATH)
            .parse::<UserId>()
            .ok()
            .map(|x| x as usize);
            // unimplemented!();
            Ok(Response::new(Body::from("user_id")))
        },
        _ => {
            let response = Response::builder()
                .status(StatusCode::NOT_FOUND)
                .body(Body::from("404"))
                .unwrap();
            Ok(response)
        }
    
    }

    // Ok(Response::new(Body::from("this is rust 4.0")))
}

#[derive(Clone)]
#[derive(Debug)]
struct AppContext {
    // Whatever data your application needs can go here
}


#[tokio::main]
async fn main() {
    let context = AppContext {
        // ...
    };
    let ko: &str = "I am here";
    println!("{}", ko);
    // let slab = Slab::new();
    let mut s = 4;
    let user_db = Arc::new(Mutex::new(UserData));
    // A `MakeService` that produces a `Service` to handle each connection.
    let make_service = make_service_fn(move |conn: &AddrStream| {
        let context = context.clone();

        let user_db = user_db.clone();
        let addr = conn.remote_addr();

        let service = service_fn(move |req| {
            handle(context.clone(), addr, req, &user_db)
        });
        async move { Ok::<_, Infallible>(service) }
    });

    // run the server like above...
    let addr = SocketAddr::from(([127, 0, 0, 1], 3000));
    let server = Server::bind(&addr).serve(make_service);

    if let Err(e) = server.await {
        eprintln!("server error: {:?}", e);
    }
}

Error

error: captured variable cannot escape `FnMut` closure body
   --> src/main.rs:101:13
    |
97  |         let user_db = user_db.clone();
    |             ------- variable defined here
...
100 |         let service = service_fn(move |req| {
    |                                           - inferred to be a `FnMut` closure
101 |             handle(context.clone(), addr, req, &user_db)
    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^-------^
    |             |                                   |
    |             |                                   variable captured here
    |             returns a reference to a captured variable which escapes the closure body
    |
    = note: `FnMut` closures only have access to their captured variables while they are executing...
    = note: ...therefore, they cannot allow references to captured variables to escape

I didn't dig into hyper to see what exactly is going on, but one way to work around the error is to have handle take a UserDb instead of a &UserDb, and to clone the captured user_db when calling it.

Playground.

sorry didnt work

If you post the new code and error, perhaps someone can try again to help.