Rust 程序设计语言 web server
1 web server 源码
// src/bin/main.rs
use std::fs;
use std::io::prelude::*;
use std::net::{TcpListener, TcpStream};
use web_server::ThreadPool;
fn main() {
let listener = TcpListener::bind("127.0.0.1:9981").unwrap();
let pool = ThreadPool::new(4);
for stream in listener.incoming() {
pool.execute(|| {
handle_connection(stream.unwrap());
});
}
}
fn handle_connection(mut stream: TcpStream) {
let mut buffer = [0; 1024];
let _size = stream.read(&mut buffer).unwrap();
let get = b"GET / HTTP/1.1\r\n";
let sleep = b"GET /sleep HTTP/1.1\r\n";
let response;
let (status_line, filename) = if buffer.starts_with(get) {
("HTTP/1.1 200 OK", "hello.html")
} else if buffer.starts_with(sleep) {
std::thread::sleep(std::time::Duration::from_secs(5));
("HTTP/1.1 200 OK", "hello.html")
} else {
("HTTP/1.1 404 Not Found", "404.html")
};
let body = fs::read_to_string(filename).unwrap();
response = format!("{}\r\nContent-Length: {}\r\n\r\n{}", status_line, body.len(), body);
stream.write(response.as_bytes()).unwrap();
}
// src/lib.rs
use std::sync::{Arc, Mutex, mpsc};
type Job = Box<dyn FnOnce() + Send + 'static>;
enum Message {
NewJob(Job),
Terminate,
}
pub struct ThreadPool {
workers: Vec<Worker>,
sender: mpsc::Sender<Message>,
}
impl ThreadPool {
pub fn new(size: usize) -> Self {
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, receiver.clone()));
}
Self { workers, sender }
}
pub fn execute<F>(&self, f: F)
where F: FnOnce() + Send + 'static,
{
let job = Box::new(f);
self.sender.send(Message::NewJob(job)).unwrap();
}
}
impl Drop for ThreadPool {
fn drop(&mut self) {
println!("Sending terminate message to all workers.");
for _ in &self.workers {
self.sender.send(Message::Terminate).unwrap();
}
println!("Shutting down all workers.");
for worker in &mut self.workers {
println!("Shutting down worker {}", worker.id);
if let Some(thread) = worker.thread.take() {
thread.join().unwrap();
}
}
}
}
struct Worker {
id: usize,
thread: Option<std::thread::JoinHandle<()>>,
}
impl Worker {
fn new(id: usize, receiver: Arc<Mutex<mpsc::Receiver<Message>>>) -> Self {
Self {
id,
thread: Some(std::thread::spawn(move || {
loop {
let message = receiver.lock().unwrap().recv().unwrap();
match message {
Message::NewJob(job) => {
println!("Worker {} got a job; executing.", id);
job()
},
Message::Terminate => {
println!("Worker {} was told to terminate.", id);
break
},
}
}
// 错误：job() 执行完才会释放锁
// recv() 会阻塞当前线程
// while let Ok(job) = receiver.lock().unwrap().recv() {
// println!("Worker {} get a job; executing.", id);
// job();
// }
})),
}
}
}
2 web server (tokio)
// src/main.rs
mod thread_pool;
use std::io::prelude::*;
use std::net::{TcpListener, TcpStream};
use thread_pool::ThreadPool;
use tokio;
#[tokio::main]
async fn main() {
let listener = TcpListener::bind("127.0.0.1:9981").unwrap();
let thread_pool = ThreadPool::new(4);
for stream in listener.incoming() {
thread_pool.execute(|| {
handle_connection(stream.unwrap());
}).await;
}
}
fn handle_connection(mut stream: TcpStream) {
let mut buffer = [0; 1024];
stream.read(&mut buffer).unwrap();
let get = b"GET / HTTP/1.1\r\n";
let sleep = b"GET /sleep HTTP/1.1\r\n";
let response;
let (status_line, content) = if buffer.starts_with(get) {
("HTTP/1.1 200 OK", "Hello Rust")
} else if buffer.starts_with(sleep) {
std::thread::sleep(std::time::Duration::from_secs(5));
("HTTP/1.1 200 OK", "Hello Rust")
} else {
("HTTP/1.1 404 Not Found", "Not Found")
};
response = format!("{}\r\nContent-Length: {}\r\n\r\n{}", status_line, content.len(), content);
stream.write(response.as_bytes()).unwrap();
}
// src/thread_pool.rs
use std::time::{SystemTime, UNIX_EPOCH};
use futures::executor::block_on;
use tokio::sync::mpsc;
type Task = Box<dyn FnOnce() + Send + 'static>;
enum Message {
NewTask(Task),
Terminate,
}
pub struct ThreadPool {
senders: Vec<(Worker, mpsc::Sender<Message>)>,
}
impl ThreadPool {
pub fn new(size: usize) -> Self {
assert!(size > 0);
let mut senders = Vec::new();
for id in 0..size {
senders.push(Worker::new(id));
}
Self { senders }
}
pub async fn execute<F>(&self, f: F)
where F: FnOnce() + Send + 'static,
{
let time = SystemTime::now().duration_since(UNIX_EPOCH).unwrap().as_micros();
let len = self.senders.len();
let index = (time % len as u128) as usize;
let (_, sender) = self.senders.get(index).unwrap();
sender.send(Message::NewTask(Box::new(f))).await;
}
}
impl Drop for ThreadPool {
fn drop(&mut self) {
println!("Sending terminate message to all workers.");
for i in 0..self.senders.len() {
let (_, sender) = self.senders.get(i).unwrap();
block_on(async {
sender.send(Message::Terminate).await;
});
}
println!("Shutting down all workers.");
for (worker, _) in &mut self.senders {
println!("Shutting down worker {}", worker.id);
if let Some(thread) = worker.thread.take() {
thread.join().unwrap();
}
}
}
}
struct Worker {
id: usize,
thread: Option<std::thread::JoinHandle<()>>,
}
impl Worker {
fn new(id: usize) -> (Worker, mpsc::Sender<Message>) {
let (tx, mut rx) = mpsc::channel::<Message>(32);
let thread = std::thread::spawn(move || block_on(
async move {
while let Some(message) = rx.recv().await {
match message {
Message::NewTask(task) => {
println!("Worker {} got a job; executing.", id);
task();
},
Message::Terminate => {
println!("Worker {} was told to terminate.", id);
break;
}
}
}
}
));
let worker = Worker { id, thread: Some(thread) };
(worker, tx)
}
}
// Cargo.toml
[package]
name = "web_server"
version = "0.1.0"
edition = "2021"
[dependencies]
tokio = { version = "1.15.0", features = ["full"] }
futures = "0.3"