Order Book

Real-time best bid, best ask, and last chance updates

Use this stream for live order book updates by event.

Endpoint

wss://order-book.outpoll.com/event/ws

Authentication

No authentication required.

Message envelope

Every message uses the same top-level fields:

{
  "t": "<TYPE>",
  "e": "<EVENT_ID>",
  "d": [...],
  "r": "<ERROR_MESSAGE>"
}

Field	Type	Description
t	string	Message type
e	string	Event ID
d	array	Outcome price payload
r	string	Error message for failed calls

Message types

Type	Direction	Description
SUBSCRIBE	Client	Subscribe to one event
SUBSCRIBED	Server	Subscription confirmed
UNSUBSCRIBE	Client	Remove one subscription
UNSUBSCRIBED	Server	Unsubscribe confirmed
REQUEST_DATA	Client	Request a full snapshot
PRICES_DATA	Server	Full price snapshot
PRICES_DATA_DELTA	Server	Incremental price update
PING	Server	Heartbeat
ERROR	Server	Request error

Subscribe

{
  "t": "SUBSCRIBE",
  "e": "54ccea1a-16fd-469c-8018-84b375243e8a"
}

Server confirmation:

{
  "t": "SUBSCRIBED",
  "e": "54ccea1a-16fd-469c-8018-84b375243e8a"
}

Price payload

PRICES_DATA sends the current state.

PRICES_DATA_DELTA sends only changed outcomes.

{
  "t": "PRICES_DATA",
  "e": "54ccea1a-16fd-469c-8018-84b375243e8a",
  "d": [
    {
      "o": "b21f6fd8-b9d1-4b9f-bb79-ef141e3dcb76",
      "c": 0.55,
      "b": 0.54,
      "a": 0.56
    }
  ]
}

Field	Type	Description
o	string	Outcome ID
c	number	Last chance
b	number	Best bid
a	number	Best ask

Python example

order_book.py

import asyncio, json, websockets

async def order_book():
    uri = "wss://order-book.outpoll.com/event/ws"
    async with websockets.connect(uri) as ws:
        await ws.send(json.dumps({
            "t": "SUBSCRIBE",
            "e": "54ccea1a-16fd-469c-8018-84b375243e8a",
        }))

        async for msg in ws:
            data = json.loads(msg)
            if data["t"] in ("PRICES_DATA", "PRICES_DATA_DELTA"):
                for price in data["d"]:
                    print(price["o"], price["c"], price["b"], price["a"])