【Rust】多线程服务器

2023-07-15 07:31•数据库•阅读 4135

环境

Rust 1.56.1
VSCode 1.61.2

概念

参考：https://doc.rust-lang.org/stable/book/ch20-02-multithreaded.html

示例

main.rs

use std::fs;
use std::io::Read;
use std::io::Write;
use std::net::TcpListener;
use std::net::TcpStream;
use std::thread;
use std::time::Duration;

fn main() {
    let listener = TcpListener::bind("127.0.0.1:7878").unwrap();
    let pool = game::ThreadPool::new(4);

    for stream in listener.incoming() {
        let stream = stream.unwrap();

        pool.execute(|| {
            handle_connection(stream);
        });
    }
}

fn handle_connection(mut stream: TcpStream) {
    println!("sleep 10 seconds");
    thread::sleep(Duration::from_secs(10));
    println!("sleep 10 seconds end");
    let mut buffer = [0; 1024];
    let length = stream.read(&mut buffer).unwrap();

    if length == 0 {
        println!("EOF");
    }

    let contents = fs::read_to_string("hello.html").unwrap();
    let response = format!(
        "HTTP/1.1 200 OK\r\nContent-Length: {}\r\n\r\n{}",
        contents.len(),
        contents
    );

    stream.write_all(response.as_bytes()).unwrap();
    stream.flush().unwrap();
}

lib.rs

use std::{
    sync::{mpsc, Arc, Mutex},
    thread,
};

pub struct ThreadPool {
    workers: Vec<Worker>,
    sender: mpsc::Sender<Job>,
}

impl ThreadPool {
    pub fn new(size: usize) -> ThreadPool {
        assert!(size > 0);

        let (sender, receiver) = mpsc::channel();
        let receiver = Arc::new(Mutex::new(receiver));
        let mut workers = Vec::with_capacity(size);

        for id in 0..size {
            workers.push(Worker::new(id, Arc::clone(&receiver)));
        }

        ThreadPool { workers, sender }
    }

    pub fn execute<F>(&self, f: F)
    where
        F: FnOnce() + Send + 'static,
    {
        let job = Box::new(f);
        self.sender.send(job).unwrap();
    }
}

struct Worker {
    id: usize,
    thread: thread::JoinHandle<()>,
}

type Job = Box<dyn FnOnce() + Send + 'static>;

impl Worker {
    fn new(id: usize, receiver: Arc<Mutex<mpsc::Receiver<Job>>>) -> Worker {
        let thread = thread::spawn(move || loop {
            let job = receiver.lock().unwrap().recv().unwrap();

            println!("Worker {} got a job; executing.", id);

            job();
        });

        Worker { id, thread }
    }
}

hello.html

<!DOCTYPE html>
<html >

<head>
    <meta charset="utf-8">
    <title>Hello!</title>
</head>

<body>
    <h1>Hello!</h1>
    <p>Hi from Rust</p>
</body>

</html>

总结

使用 rust 实现了一个多线程的 web 服务器。

附录