前面我们发送的大多数都是text类型的消息，对于text消息来说，后端处理出来要麻烦的多，那么我们可以不可以传递json格式的数据，对于前后端来说都比较友好，答案是肯定的，我们需要做下处理。
首先，我们在websocket管理器中增加处理json格式消息的方法：
from typing import List, Dict
from starlette.websockets import WebSocket
class ConnectionManager:
def __init__(self):
"""存放链接"""
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})
async def disconnect(self, user: str, ws: WebSocket):
"""断开链接，移除"""
self.active_connections.remove({"user": user, "ws": ws})
@staticmethod
async def send_personal_message(message: str, ws: WebSocket):
"""发送所有人消息"""
await ws.send_text(message)
async def send_other_message(self, message: dict, user: str):
"""发送个人消息"""
for coon in self.active_connections:
if coon["user"] == user:
await coon["ws"].send_json(message)
async def broadcast(self, data: str):
"""广播"""
for conn in self.active_connections:
await conn["ws"].send_text(data)
async def broadcast_json(self, data: dict):
"""广播json数据"""
for conn in self.active_connections:
await conn["ws"].send_json(data)接口中如何接收json数据呢，新增接口如下：
@app.websocket("/ws/json/{user}")
async def websocket_json_data(
websocket: WebSocket,
user: str,
cookie_or_token: str = Depends(get_cookie_or_token)
):
"""发送接收json数据（前面一对一接口其实就是发送的json数据）"""
await ws_manager.connect(user, websocket)
try:
while True:
data = await websocket.receive_json()
send_user = data["username"]
if send_user:
await ws_manager.send_other_message(data, send_user)
else:
await ws_manager.broadcast_json(data)
except WebSocketDisconnect as e:
await ws_manager.disconnect(user, websocket)
前端也要相对应的修改：
<!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/json/"+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>
部署看效果，因为发送给后端的数据格式是前端拼的json，所以页面上只需要填文本即可：
