Realtime & WebSocket API Reference

The realtime worker of the API streams 1-minute ticks from TradingView, stores the last tick of each ticker in Redis (quote:{ticker}, 60 s), publishes it on the Redis channel price:{ticker} and saves it in the prices_intraday hypertable when the instrument is in the catalogue.

Streams are started by a full-access key: by POST /realtime/subscribe, or by connecting to the WebSocket. A read-only key never starts a stream; it is served what is already streamed. Subscriptions of tickers that name an instrument of the catalogue are stored in realtime_subscriptions and restored when the API starts; other tickers are streamed but not restored after a restart.

---

WS /ws/realtime/{ticker}

const ws = new WebSocket(`ws://localhost:5000/ws/realtime/AIR.PA?token=${FONREX_API_KEY}`);

The key is checked during the handshake. A WebSocket client can send it as a header (Authorization or X-API-KEY) or in the query string as token, api_key or key. A missing or wrong key closes the connection with code 1008.

Messages sent by the server

Every message has the form {"type", "ticker", "data", "error", "ts"}, except pong, sent as {"type": "pong"}.

type	When	data
not_streaming	Read-only key on a ticker that is not streamed (sent first; error explains it)	—
snapshot	Right after the connection, when a last tick is cached	The last tick
tick	Each new tick	The tick
pong	Answer to a ping from the client	—

{
  "type": "tick",
  "ticker": "AIR.PA",
  "data": {
    "ticker": "AIR.PA",
    "timestamp": "2026-10-08T09:31:00Z",
    "open": "155.20",
    "high": "155.48",
    "low": "155.10",
    "close": "155.42",
    "volume": 18250,
    "source": "tradingview",
    "exchange": null,
    "currency": null
  },
  "error": null,
  "ts": "2026-10-08T09:31:02.114Z"
}

Prices are decimal numbers serialised as strings.

Messages sent by the client

Text	Effect
ping	The server answers {"type": "pong"}
unsubscribe	The server closes the connection

The TradingView symbol is derived from the ticker suffix (AIR.PA → EURONEXT:AIR, .DE → XETRA); a ticker without suffix is taken for a NASDAQ line.

---

GET /quote/{ticker}

The last known price of a ticker.

Parameter	Type	Default	Description
subscribe_if_missing	boolean	false	Also start the stream of the ticker in the background. Ignored for a read-only key

When the ticker is streamed, the cached tick is returned (is_realtime: true, source: "tradingview"). Otherwise Fonrex returns the delayed Yahoo Finance price of the ticker as typed (is_realtime: false, source: "yfinance", delay_seconds: 900). Nothing found answers 404. A tick carries no previous close: for a streamed ticker change and change_pct are 0 and previous_close is null; the delayed Yahoo answer fills them.

{
  "ticker": "AIR.PA",
  "price": "155.42",
  "open": "155.20",
  "high": "155.48",
  "low": "155.10",
  "close": "155.42",
  "volume": 18250,
  "change": "0",
  "change_pct": "0",
  "previous_close": null,
  "timestamp": "2026-10-08T09:31:00Z",
  "is_realtime": true,
  "source": "tradingview",
  "delay_seconds": 0
}

---

GET /quotes

Quotes of several tickers: tickers is a comma-separated list, cut to the first 20. A ticker without a quote is null. This route never starts a stream.

{ "count": 2, "tickers": ["AIR.PA", "BNP.PA"], "quotes": { "AIR.PA": { "...": "..." }, "BNP.PA": null } }

---

POST /realtime/subscribe

Start the stream of up to 50 tickers. Full-access key only.

curl -s -X POST -H "X-API-KEY: $FONREX_API_KEY" -H "Content-Type: application/json" \
  -d '{"tickers": ["AIR.PA", "BNP.PA"]}' http://localhost:5000/realtime/subscribe

[
  {
    "ticker": "AIR.PA",
    "tv_exchange": "EURONEXT",
    "tv_symbol": "AIR",
    "is_active": true,
    "subscribed_at": "2026-10-08T09:30:00Z",
    "last_tick_at": null,
    "tick_count": 0,
    "is_streaming": true
  }
]

---

DELETE /realtime/subscribe/{ticker}

Stop the stream of a ticker. Full-access key only. Answers {"status": "unsubscribed", "ticker": "AIR.PA"}, or 404 when the ticker is not streamed.

---

GET /realtime/status

{
  "streaming_count": 1,
  "active_tickers": ["AIR.PA"],
  "ws_connections": { "AIR.PA": 2 },
  "total_ws_clients": 2,
  "stale_tickers": [],
  "worker_running": true
}

stale_tickers lists streamed tickers without a fresh tick in Redis.