Python開發 之 Websocket 的使用示例

1、嘮嘮叨叨

最近又回顧了下Websocket，發現已經忘的七七八八了。於是用js寫了客戶端，用python寫了服務端，來復習一下這方面的知識。

2、先看一下效果吧

2.1、效果1（一個客戶端連上服務的並發送消息）

 

2.2、效果2（另一個客戶端連上服務的並發送消息）

 

2.3、效果3（服務的收到客戶端的全部消息並返回消息）

 

 

2.4、效果4（一個客戶端掉線並不影響其它socket連接）

 

 

2.5、效果5（列取全部連接客戶端對象和當前發消息的客戶端對象）

 

 

3、核心代碼

3.1、Python

#! -*- coding: utf-8 -*-
"""
Author: ZhenYuSha
Create Time: 2019-1-14
Info: Websocket 的使用示例
"""
import asyncio
import websockets

websocket_users = set()


# 檢測客戶端權限，用戶名密碼通過才能退出循環
async def check_user_permit(websocket):
    print("new websocket_users:", websocket)
    websocket_users.add(websocket)
    print("websocket_users list:", websocket_users)
    while True:
        recv_str = await websocket.recv()
        cred_dict = recv_str.split(":")
        if cred_dict[0] == "admin" and cred_dict[1] == "123456":
            response_str = "Congratulation, you have connect with server..."
            await websocket.send(response_str)
            print("Password is ok...")
            return True
        else:
            response_str = "Sorry, please input the username or password..."
            print("Password is wrong...")
            await websocket.send(response_str)


# 接收客戶端消息並處理，這里只是簡單把客戶端發來的返回回去
async def recv_user_msg(websocket):
    while True:
        recv_text = await websocket.recv()
        print("recv_text:", websocket.pong, recv_text)
        response_text = f"Server return: {recv_text}"
        print("response_text:", response_text)
        await websocket.send(response_text)


# 服務器端主邏輯
async def run(websocket, path):
    while True:
        try:
            await check_user_permit(websocket)
            await recv_user_msg(websocket)
        except websockets.ConnectionClosed:
            print("ConnectionClosed...", path)    # 鏈接斷開
            print("websocket_users old:", websocket_users)
            websocket_users.remove(websocket)
            print("websocket_users new:", websocket_users)
            break
        except websockets.InvalidState:
            print("InvalidState...")    # 無效狀態
            break
        except Exception as e:
            print("Exception:", e)


if __name__ == '__main__':
    print("127.0.0.1:8181 websocket...")
    asyncio.get_event_loop().run_until_complete(websockets.serve(run, "127.0.0.1", 8181))
    asyncio.get_event_loop().run_forever()

3.2、Html（JS）

    <script>
        var socket;
        if ("WebSocket" in window) {
            var ws = new WebSocket("ws://127.0.0.1:8181/test");
            socket = ws;
            ws.onopen = function() {
                console.log('連接成功');
                alert("連接成功, 請輸入賬號和密碼");
            };
            ws.onmessage = function(evt) {
                var received_msg = evt.data;
                document.getElementById("showMes").value+=received_msg+"\n";
            };
            ws.onclose = function() {
                alert("斷開了連接");
            };
        } else {
            alert("瀏覽器不支持WebSocket");
        }
        function sendMeg(){
            var message=document.getElementById("name").value+":"+document.getElementById("mes").value;
            document.getElementById("showMes").value+=message+"\n\n";
            socket.send(message);
        }
    </script>