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FastAPI 学习之路（五十二）WebSockets(八)接受/发送json格式消息

相对于之前的text的消息来说，我们之前发送的消息都是text的居多，那么对于text格式的消息来说，我们处理起来，尤其是后端要麻烦的多，那么我们可不可以传递json格式的，对于前后端来说都好处理的一种格式的消息，那么答案来说是可以的。我们需要做下处理。

我们在之前的websockets管理中的的消息的处理全部改造成json格式的。我们看下如何处理呢

class ConnectionManager:
    def __init__(self):
        # 存放**的链接
        self.active_connections: List[Dict[str, WebSocket]] = []

    async def connect(self, user: str, ws: WebSocket):
        # 链接
        await ws.accept()
        self.active_connections.append({"user": user, "ws": ws})

    def disconnect(self, user: str, ws: WebSocket):
        # 关闭时 移除ws对象
        self.active_connections.remove({"user": user, "ws": ws})


    async def send_other_message_json(self, message: dict, user: str):
        # 发送个人消息
        for connection in self.active_connections:
            if connection["user"] == user:
                await connection['ws'].send_json(message)

    async def broadcast_json(self, data: dict):
        # 广播消息
        for connection in self.active_connections:
            await connection['ws'].send_json(data)

我们现在所有的消息，我们只支持的json格式呢，我们可以对的处理消息，

manager = ConnectionManager()


@app.websocket("/ws/{user}/")
async  def websocket_many_point(
        websocket: WebSocket,
        user:str,
        cookie_or_token: str = Depends(get_cookie_or_token),
        ):
    print(user)
    await manager.connect(user, websocket)
    try:
        while True:
            data = await websocket.receive_json()
            senduser=data['username']
            if senduser:
                await manager.send_other_message_json(data,senduser)
            else:
                await  manager.broadcast_json(data)
    except WebSocketDisconnect as e:
        manager.disconnect(user, websocket)

修改完之后，我们针对前段也需要修改，修改成支持我们的json格式数据

<!DOCTYPE html>
<html>
<head>
    <title>Chat</title>
</head>
<body>
<h1>WebSocket 聊天</h1>
<form action="" onsubmit="sendMessage(event)">
    <input type="text" id="messageText" autocomplete="off"/>
      <input type="text" id="username" autocomplete="off"/>
    <button>Send</button>
</form>
<button onclick="logout()">退出</button>
<ul id='messages'>
</ul>
<script>
    var  token=window.localStorage.getItem("token")
    if (token==null ){
        window.location.href="/login"
    }
    var ws = new WebSocket("ws://localhost:8000/ws/"+token+"/?token="+token);
 
    ws.onmessage = function (event) {
 
        var messages = document.getElementById('messages')
 
        var message = document.createElement('li')
        let receiveJson = JSON.parse(event.data);
        console.log(receiveJson)
        var content = document.createTextNode(receiveJson.username+"说:"+receiveJson.messageText)
 
        message.appendChild(content)
 
        messages.appendChild(message)
 
    };
 
    function sendMessage(event) {
 
        var input = document.getElementById("messageText")
        var username = document.getElementById("username")
        let message = {messageText: input.value, username:username.value};
        let messageJson = JSON.stringify(message);
        ws.send(messageJson);
        input.value = ''
        event.preventDefault()
 
    }
    function logout() {
        window.localStorage.removeItem("token")
        window.location.href='/login'
    }
</script>
 
</body>
 
</html>