7.2. Bảng giá phái sinh (WebSocket)

import base64

jwt_token = "eyJhbGciOiJSUzI1NiIsInR5cCI6IkpXVCJ9..."
encoded = base64.b64encode(jwt_token.encode()).decode()
auth_message = f"d|a|||{encoded}"

# Send: "d|a|||ZXlKaGJHY2lPaUpTVXpJMU5pSXNJbl..."
await ws.send(auth_message)

# Wait for response
response = await ws.recv()  # d|0|{"success":true,...} = success

"""Minimal WebSocket derivative price-board client for TCBS — Python 3.10+"""

import asyncio
import base64
import json

# pip install websockets>=12.0
from websockets.asyncio.client import connect


WS_URL = "wss://openapi.tcbs.com.vn/ws/thesis/v1/stream/derivative"
TOKEN = "YOUR_JWT_TOKEN_HERE"
SYMBOL = "41I1G8000"  # VN30F front-month


async def main():
    # 1. Connect — MUST disable auto-ping
    async with connect(WS_URL, ping_interval=None, ping_timeout=None) as ws:

        # 2. Auth — base64 encode token
        encoded_token = base64.b64encode(TOKEN.encode()).decode()
        await ws.send(f"d|a|||{encoded_token}")

        # 3. Wait for auth response
        auth_response = await asyncio.wait_for(ws.recv(), timeout=5.0)
        print(f"Auth response: {auth_response}")
        if '"success":true' not in auth_response:
            print("Auth failed!")
            return

        # 4. Subscribe
        await ws.send(f"d|s|tk|bp+bi+tm+mp+op+fe|{SYMBOL}")
        print(f"Subscribed to {SYMBOL}")

        # 5. Start heartbeat background task
        async def heartbeat():
            while True:
                await ws.send("d|p|||")
                await asyncio.sleep(2)

        asyncio.create_task(heartbeat())

        # 6. Receive & parse messages
        while True:
            raw = await ws.recv()

            # Skip control messages
            if raw.startswith("d|"):
                continue

            # Parse data: s|[channel]|[json]
            if raw.startswith("s|"):
                parts = raw.split("|", 2)
                if len(parts) == 3:
                    channel = parts[1]
                    payload = json.loads(parts[2])

                    if channel == "21":
                        print(f"[TRADE] Price={payload['matchPrice']} "
                              f"Qty={payload['matchQtty']} "
                              f"Vol={payload.get('totalVolume', 0)}")
                    elif channel == "23":
                        print(f"[BID] Best={payload['bidPrice01']} "
                              f"Qty={payload['bidQtty01']}")
                    elif channel == "24":
                        print(f"[OFFER] Best={payload['offerPrice01']} "
                              f"Qty={payload['offerQtty01']}")
                    elif channel == "27":
                        print(f"[DAY] H={payload['high']} "
                              f"L={payload['low']} O={payload['open']}")


if __name__ == "__main__":
    asyncio.run(main())