无法从外部机器连接到TCP服务器

Question

我已经在Rust中编写了一个基本的TCP服务器，但我无法从同一网络上的其他计算机访问它。这不是网络问题，因为我也编写了一个类似的Python TCP服务器，并且测试客户端能够成功连接到该服务器。

use std::io::{Read, Write}; 
use std::net::{TcpListener, TcpStream}; 
use std::thread; 
use std::str; 

fn handle_read(mut stream: TcpStream) { 
    let mut buf; 
    // clear out the buffer so we don't send garbage 
    buf = [0; 512]; 

    // Read and discard any data from the client since this is a read only server. 
    let _ = match stream.read(&mut buf) { 
     Err(e) => panic!("Got an error: {}", e), 
     Ok(m) => m, 
    }; 

    println!("Got some data"); 

    // Write back the response to the TCP stream 
    match stream.write("This works!".as_bytes()) { 
     Err(e) => panic!("Read-Server: Error writing to stream {}", e), 
     Ok(_) =>(), 
    } 

} 

pub fn read_server() { 
    // Create TCP server 
    let listener = TcpListener::bind("127.0.0.1:6009").unwrap(); 
    println!("Read server listening on port 6009 started, ready to accept"); 

    // Wait for incoming connections and respond accordingly 
    for stream in listener.incoming() { 
     match stream { 
      Err(_) => { 
       println!("Got an error"); 
      } 
      Ok(stream) => { 

       println!("Received a connection"); 
       // Spawn a new thread to respond to the connection request 
       thread::spawn(move || { 
        handle_read(stream); 

       }); 

      }  
     } 

    } 
} 

fn main() { 
    read_server(); 
} 

Answer 1

let listener = TcpListener::bind("127.0.0.1:6009").unwrap(); 

如果您绑定到127.0.0.1:xxxx，插座只能从本地主机接口听。要允许外部连接，请改为绑定到0.0.0.0，以便它可以接受来自所有网络接口的连接。

let listener = TcpListener::bind("0.0.0.0:6009").unwrap(); 

查看Why would I bind on a different server than 127.0.0.1?了解详情。

---

BTW，（1）

// not idiomatic 
let _ = match stream.read(&mut buf) { 
    Err(e) => panic!("Got an error: {}", e), 
    Ok(m) => m, 
}; 

您可以使用Result::expect这一点。

// better 
stream.read(&mut buf).expect("Got an error"); 

（2）

// not idiomatic 
match stream.write("This works!".as_bytes()) { 
    Err(e) => panic!("Read-Server: Error writing to stream {}", e), 
    Ok(_) =>(), 
} 

，而不是"aaa".as_bytes()，你可以简单地写b"aaa"。

// better 
stream.write(b"This works!").expect("Read-Server: Error writing to stream");