使用原生rust搭建http服务器

一、搭建http服务器

        在8080端口创建tcp监听，引入handle_client请求处理模块，ThreadPool模块创建多线程。

use handle::handle_client;
use std::net::TcpListener;
use thread::ThreadPool;

fn main() -> std::io::Result<()> {
  let listener = TcpListener::bind("127.0.0.1:8080")?;

  let pool = ThreadPool::new(4);

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

    pool.execute(|| handle_client(stream));
  }

  Ok(())
}

二、创建多线程

        在ThreadPool用于创建Worker,发送要执行job的函数給Worker。Worker创建后用于监听ThreadPool发送过来job函数并执行。

use std::sync::mpsc;
use std::sync::Arc;
use std::sync::Mutex;
use std::thread;

pub struct Worker {
  pub id: usize,
  pub thread: thread::JoinHandle<()>,
}
impl Worker {
  fn new(id: usize, receiver: Arc>>) -> Worker {
    // fn new(ide: usize, receiver: mpsc::Receiver) -> Worker {
    let thread = thread::spawn(move || {
      loop {
        let job = receiver.lock().unwrap().recv().unwrap();
        // println!("Worker {} got a job!", id);
        job();
      }
    });

    Worker { id, thread }
  }
}

pub struct ThreadPool {
  // workers: Vec,
  sender: mpsc::Sender,
}

type Job = Box;

impl ThreadPool {
  pub fn new(size: usize) -> ThreadPool {
    let num = if size > 0 { size } else { 1 };

    let mut workers = Vec::with_capacity(num);
    let (sender, receiver) = mpsc::channel();
    let receiver = Arc::new(Mutex::new(receiver)); //线程安全

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

    ThreadPool {
      // threads
      // workers,
      sender,
    }
  }

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

 三、请求处理模块

        在请求处理模块中引入MySQL模块，serde模块用于将数据库查询结果转换成json返回给前端。在tools中封装params_parse、send_file、send、json,分别用于获取请求类型、返回文件、返回字符串、返回json格式字符串。

use std::io::{BufReader, Read};
use std::net::TcpStream;
// use mysql::prelude::*;

mod tools;
use database::{mysql_connect, User};
use mysql::prelude::Queryable;
use serde::{Deserialize, Serialize};
use serde_json;

#[derive(Serialize, Deserialize, Debug)]
struct Json
where
  T: Serialize,
{
  arr: Vec,
}

pub fn handle_client(mut stream: TcpStream) {
  let (method, path, _protocol) = tools::params_parse(&mut stream);

  if method == "GET" {
    // 处理 GET 请求
    if path == "/" {
      tools::send_file(&mut stream, String::from("view/index.html"));
    } else if path == "/home" {
      tools::send_file(&mut stream, String::from("view/home.html"));
    } else if path == "/user" {
      let mut conn = if let Ok(conn) = mysql_connect() {
        conn
      } else {
        tools::send(&mut stream, String::from("mysql connect error!"));
        return;
      };

      // 执行查询
      let res: Result, _> = conn.query_map(
        "SELECT * from users",
        |(id, nick_name, avatar_url, job, introduce)| User {
          id,
          nick_name,
          avatar_url,
          job,
          introduce,
        },
      );

      let json = match res {
        Ok(value) => serde_json::to_string(&value).unwrap(),
        Err(_) => {
          let value = String::from("{arr:[]}");
          serde_json::to_string(&value).unwrap()
        }
      };

      tools::json(&mut stream, json);
      return;
    } else {
      tools::send(&mut stream, String::from("hello world!"));
      return;
    }
  } else if method == "POST" {
    // 处理 POST 请求
    let mut reader = BufReader::new(&mut stream);
    let mut buffer = vec![0; 1024];
    if let Err(_) = reader.read_to_end(&mut buffer) {
      tools::send(&mut stream, String::from("params parse error!"));
      return;
    };

    let request_body = String::from_utf8_lossy(&buffer).to_string();

    tools::send(&mut stream, request_body);
    return;
  } else {
    // 处理其他请求
    tools::send(&mut stream, String::from("Not Implemented"));
    return;
  }
}

四、tools.rs

        在写返回数据时，如果返回的内容在页面中没有正确显示，并且服务器已响应，那可能是没有正确的实现http协议，可能是Content-Type、Content-Length、charset等参数设置错误所导致的。

use std::fs;
use std::io::{BufRead, BufReader};
use std::io::{Read, Write};
use std::net::TcpStream;

// 解析请求类型，请求路径
pub fn params_parse(mut stream: &mut TcpStream) -> (String, String, String) {
  let mut reader = BufReader::new(&mut stream);
  let mut request_line = String::new();
  if let Err(_) = reader.read_line(&mut request_line) {
    send(&mut stream, String::from("params parse error!"));
    return (
      String::from(""),
      String::from(""),
      String::from(""),
    );
  };

  let tokens: Vec<&str> = request_line.split_whitespace().collect();

  let method = String::from(tokens[0]);
  let path = String::from(tokens[1]);
  let protocol = String::from(tokens[2]);

  println!(
    "Method: {}, Path: {}, Protocol: {}, token: {:?}",
    method, path, protocol, tokens
  );

  (method, path, protocol)
}

pub fn send_file(stream: &mut TcpStream, file_path: String) {
  // 如果打开文件失败
  let mut file = match fs::File::open(file_path) {
    Ok(file) => file,
    Err(_) => {
      let response = "HTTP/1.1 404 Not Found\r\n\r\n";
      stream.write(response.as_bytes()).unwrap();
      return;
    }
  };

  // thread::sleep(time::Duration::from_millis(1000));

  let mut contents = String::new();
  // 如果读取内容失败
  if let Err(_) = file.read_to_string(&mut contents) {
    let response = "HTTP/1.1 500 Internal Server Error\r\n\r\n";
    stream.write(response.as_bytes()).unwrap();
    return;
  }
  let response = format!(
    "HTTP/1.1 200 OK\r\nContent-Type: text/html; charset=UTF-8\r\nContent-Length: {}\r\n\r\n{}",
    contents.len(),
    contents
  );
  stream.write(response.as_bytes()).unwrap();

  stream.flush().unwrap();
}

pub fn send(stream: &mut TcpStream, content: String) {
  let response = format!(
    "HTTP/1.1 200 OK\r\nContent-Type: text/html; charset=UTF-8\r\nContent-Length: {}\r\n\r\n{}",
    content.len(),
    content
  );
  stream.write(response.as_bytes()).unwrap();
  stream.flush().unwrap();
}

pub fn json(stream: &mut TcpStream, json: String) {
  let response = format!(
    "HTTP/1.1 200 OK\r\nContent-Type: application/json; charset=utf-8\r\nContent-Length: {}\r\n\r\n{}",
    json.len(),
    json
  );
  stream.write(response.as_bytes()).unwrap();
  stream.flush().unwrap();
}

五、数据库连接

use mysql::*;
use serde::Serialize;

#[derive(Serialize, Debug, PartialEq, Eq)]
pub struct User {
  pub id: i32,
  pub nick_name: String,
  pub avatar_url: String,
  pub job: String,
  pub introduce: String,
}

pub fn mysql_connect() -> std::result::Result> {
  let url = "mysql://root:root@localhost:3306/test";

  let pool = Pool::new(url)?;

  let conn = pool.get_conn()?;

  return Ok(conn);
}

使用到的第三方库mysql、serde、serde_json。