Start a Market Data Stream

#!/usr/bin/env python3

import asyncio
from datetime import datetime
import requests
import sys
import websockets
import Tokens #Tokens stored separately for security

# Tokens stored separately for security
API_TOKEN = Tokens.API_TOKEN
TEST_TOKEN = Tokens.TEST_TOKEN


# Potential lists of equities to track

TOP10 = '["AAPL","MSFT","NVDA","AMZN","META","GGOGL","GOOG","BRK.B","LLY","AVGO"]'
TOP15 = '["AAPL","MSFT","NVDA","AMZN","META","GGOGL","GOOG","BRK.B","LLY","AVGO","TSLA", "JPM","UNH","XOM","V"]'
SINGLE = '["SPCX"]'

async def reconnect():
    timestamp = 0

    while(True):
        if isinstance(timestamp, datetime):
            delta = (datetime.now() - timestamp)
        if (timestamp == 0 or ((delta.seconds % 3600) // 60) > 5):
            response = requests.post('https://api.tradier.com/v1/markets/events/session',
                data={},
                headers={'Authorization': f'Bearer {API_TOKEN}', 'Accept': 'application/json'}
            )

            if response.status_code == 401:
                print("Token request respsponse: {}".format(response))
                print(response.text)
                sys.exit(1)
            else:
                json_response = response.json()
                SESSION_ID = json_response['stream']['sessionid']
                timestamp = datetime.now()

        PAYLOAD = '{"symbols": ' + SINGLE + ', "filter": ["quote"], "sessionid": "' + SESSION_ID + '", "linebreak": true, "validOnly": false, "advancedDetails": true}'
        uri = "wss://ws.tradier.com/v1/markets/events"

        try:
            async with websockets.connect(uri, ssl=True, compression=None) as websocket:
                payload = PAYLOAD
                print(payload)
                await websocket.send(payload)

                print(f">>> {payload}")

                async for message in websocket:
                    print(f"<<< {datetime.now()}{message}")
        except websockets.ConnectionClosed:
            print("WebSocket connection closed. Reconnecting...")
            await asyncio.sleep(5)

asyncio.run(reconnect())

>>> {"symbols": ["SPCX"], "filter": ["quote"], "sessionid": "b54d1f03-3ffc-425a-855d-2c9218c75f0b", "linebreak": true, "validOnly": false, "advancedDetails": true}
<<< 2026-08-09 23:11:25.436888{"type":"quote","symbol":"SPCX","bid":134.07,"bidsz":500,"bidexch":"P","biddate":"1786147198000","ask":134.11,"asksz":300,"askexch":"Q","askdate":"1786147199000"}