Quart，聊天服务器示例答案

【问题标题】：Quart, chat server exampleQuart，聊天服务器示例
【发布时间】：2021-11-13 12:22:59
【问题描述】：

我正在尝试同时使用多个 websocket 制作一个 quart 应用程序：

<script type="text/javascript">
         let socket = new WebSocket('ws://localhost:5000/mensagens/{{ dialog_id }}');
         socket.onmessage = function(event) {
                  var messages_dom = document.getElementsByTagName('ul')[0];
                  var message_dom = document.createElement('li');
                  var cotent_dom = document.createTextNode(event.data);
                  message_dom.appendChild(cotent_dom);
                  messages_dom.appendChild(message_dom);
         };
</script>

<script>
         let ws = new WebSocket('ws://localhost:5000/printar/12');
         function myFunction() {
                  var x = document.getElementById("myText").value;
                  ws.send(x);
                  document.getElementById("demo").innerHTML = x;
    };
</script>

这是服务器端：

#Quart
from quart import Quart, render_template, url_for, websocket, redirect, request

#asyncio
import asyncio

app = Quart(__name__)

...
#websocket da conversa individual
@app.websocket('/mensagens/<dialog_id>')
async def mensagens(dialog_id):
         print("123");
         try:
                  output = await ".....function that updates from the SQLite database....";
                  await websocket.send(f"{output}");
         
         await asyncio.sleep(1);

         except Exception as e:
                  print("-------");
                  print(e);

#websocket de enviar mensagens
@app.websocket('/printar/<dialog_id>')
async def printar(dialog_id):
         print("aqui");
         try:         
                  while True:
                           print(dialog_id);
                           data = await websocket.receive();
                           print(data + "\n=====");

         except Exception as e:
                  print(e);


if __name__ == "__main__":
    try:
        app.run();

    except KeyboardInterrupt:
        print("=====\nAdeus!\n=====");

    except Exception as e:
        print(e);

但是，出于某种原因，第二个 websocket 仅在第一个 websocket 收到来自“mensagens”的更新后才开始运行。我真的不明白发生了什么以及为什么会发生。

有没有我可以看的用 Quart 制作的聊天服务器的例子？

【问题讨论】：

标签： javascript python websocket chat quart

【解决方案1】：

所以...我是白痴。我刚刚找到this，其中解释了接收和发送的用户独立（另外，我对 asyncio 不太擅长）。

不管怎样，这里有一个例子：

<!doctype html>
<html>
  <head>
    <title>Quart + SQLite</title>
  </head>
  <body>
  <h1>Testes!</h1>

  <div class="mensagens">
     <ul></ul>
  </div>

  Mensagem: <input type="text" id="myText" value="Mickey">

  <p>Escreva suas mensagens acima!</p>

  <button onclick="myFunction()">Enviar</button>

  <p id="demo"></p>

  <script>
  let socket = new WebSocket('ws://localhost:5000/ws/12');
  function myFunction() {
    var x = document.getElementById("myText").value;
    socket.send(x);
    document.getElementById("demo").innerHTML = x;
  };

  socket.onmessage = function(event) {
    var messages_dom = document.getElementsByTagName('ul')[0];
    var message_dom = document.createElement('li');
    var cotent_dom = document.createTextNode(event.data);
    message_dom.appendChild(cotent_dom);
    messages_dom.appendChild(message_dom);
  };
  </script>

  </body>
</html>

这里是python方面：

#https://pgjones.gitlab.io/quart/how_to_guides/websockets.html
#Quart
from quart import Quart, render_template, url_for, websocket, redirect, request
import asyncio

app = Quart(__name__)

async def sending():
    while True:
        await websocket.send('f{1}');
        asyncio.sleep(1);

async def receiving():
    while True:
        data = await websocket.receive();
        print(data + "\n=====");
        
        

@app.websocket('/ws/<num>')
async def ws(num):
    print(num);
    producer = asyncio.create_task(sending());
    consumer = asyncio.create_task(receiving());
    await asyncio.gather(producer, consumer);

@app.route('/')
async def main():
    return await render_template('teste_html.html');


if __name__ == '__main__':
    try:
        app.run();

    except KeyboardInterrupt:
        print("=====\nAdeus!\n=====");

    except Exception as e:
        print(e);

【讨论】：