101 lines
3.3 KiB
Python
101 lines
3.3 KiB
Python
import json
|
|
|
|
from channels.db import database_sync_to_async
|
|
from channels.generic.websocket import AsyncJsonWebsocketConsumer
|
|
|
|
from .models import BoardSession
|
|
|
|
|
|
class BoardConsumer(AsyncJsonWebsocketConsumer):
|
|
async def connect(self):
|
|
self.session_id = self.scope["url_route"]["kwargs"]["session_id"]
|
|
self.group_name = f"board_{self.session_id}"
|
|
user = self.scope["user"]
|
|
if not user.is_authenticated or not await self._is_participant(user.id):
|
|
await self.close(code=4403)
|
|
return
|
|
await self.channel_layer.group_add(self.group_name, self.channel_name)
|
|
await self.accept()
|
|
await self.send_json(
|
|
{
|
|
"type": "connected",
|
|
"session_id": str(self.session_id),
|
|
}
|
|
)
|
|
|
|
async def disconnect(self, close_code):
|
|
if hasattr(self, "group_name"):
|
|
await self.channel_layer.group_discard(
|
|
self.group_name,
|
|
self.channel_name,
|
|
)
|
|
|
|
async def receive_json(self, content, **kwargs):
|
|
event_type = content.get("type")
|
|
if event_type == "ping":
|
|
await self.send_json({"type": "pong"})
|
|
return
|
|
if event_type not in {"canvas", "geometry"}:
|
|
await self.send_json({"type": "error", "message": "不支持的画板消息"})
|
|
return
|
|
if not await self._is_active():
|
|
await self.send_json({"type": "error", "message": "画板尚未开始或已经结束"})
|
|
return
|
|
payload = content.get("payload")
|
|
if event_type == "canvas":
|
|
valid = (
|
|
isinstance(payload, str)
|
|
and payload.startswith("data:image/")
|
|
and len(payload) <= 700_000
|
|
)
|
|
else:
|
|
valid = isinstance(payload, dict) and len(
|
|
json.dumps(payload, ensure_ascii=False)
|
|
) <= 100_000
|
|
if not valid:
|
|
await self.send_json({"type": "error", "message": "画板消息无效或过大"})
|
|
return
|
|
await self.channel_layer.group_send(
|
|
self.group_name,
|
|
{
|
|
"type": "board.update",
|
|
"event_type": event_type,
|
|
"payload": payload,
|
|
"user_id": str(self.scope["user"].id),
|
|
},
|
|
)
|
|
|
|
async def board_update(self, event):
|
|
await self.send_json(
|
|
{
|
|
"type": event["event_type"],
|
|
"payload": event["payload"],
|
|
"user_id": event["user_id"],
|
|
}
|
|
)
|
|
|
|
async def board_state(self, event):
|
|
await self.send_json(
|
|
{
|
|
"type": "state",
|
|
"reason": event["reason"],
|
|
"session_id": str(self.session_id),
|
|
}
|
|
)
|
|
|
|
@database_sync_to_async
|
|
def _is_participant(self, user_id):
|
|
return BoardSession.objects.filter(id=self.session_id).filter(
|
|
host_id=user_id
|
|
).exists() or BoardSession.objects.filter(
|
|
id=self.session_id,
|
|
guest_id=user_id,
|
|
).exists()
|
|
|
|
@database_sync_to_async
|
|
def _is_active(self):
|
|
return BoardSession.objects.filter(
|
|
id=self.session_id,
|
|
status=BoardSession.Status.ACTIVE,
|
|
).exists()
|