Files
bitfinex-api-py/examples/websocket/public/raw_order_book.py
2023-12-14 19:18:57 +01:00

127 lines
3.7 KiB
Python

# python -c "import examples.websocket.public.raw_order_book"
import zlib
from collections import OrderedDict
from typing import Any, Dict, List, cast
from bfxapi import Client
from bfxapi.types import TradingPairRawBook
from bfxapi.websocket.subscriptions import Book
class RawOrderBook:
def __init__(self, symbols: List[str]):
self.__raw_order_book = {
symbol: {"bids": OrderedDict(), "asks": OrderedDict()} for symbol in symbols
}
def update(self, symbol: str, data: TradingPairRawBook) -> None:
order_id, price, amount = data.order_id, data.price, data.amount
kind = "bids" if amount > 0 else "asks"
if price > 0:
self.__raw_order_book[symbol][kind][order_id] = {
"order_id": order_id,
"price": price,
"amount": amount,
}
if price == 0:
if order_id in self.__raw_order_book[symbol][kind]:
del self.__raw_order_book[symbol][kind][order_id]
def verify(self, symbol: str, checksum: int) -> bool:
values: List[int] = []
bids = sorted(
[
(data["order_id"], data["price"], data["amount"])
for _, data in self.__raw_order_book[symbol]["bids"].items()
],
key=lambda data: (-data[1], data[0]),
)
asks = sorted(
[
(data["order_id"], data["price"], data["amount"])
for _, data in self.__raw_order_book[symbol]["asks"].items()
],
key=lambda data: (data[1], data[0]),
)
if len(bids) < 25 or len(asks) < 25:
raise AssertionError("Not enough bids or asks (need at least 25).")
for _i in range(25):
bid, ask = bids[_i], asks[_i]
values.extend([bid[0], bid[2]])
values.extend([ask[0], ask[2]])
local = ":".join(str(value) for value in values)
crc32 = zlib.crc32(local.encode("UTF-8"))
return crc32 == checksum
def is_verifiable(self, symbol: str) -> bool:
return (
len(self.__raw_order_book[symbol]["bids"]) >= 25
and len(self.__raw_order_book[symbol]["asks"]) >= 25
)
def clear(self, symbol: str) -> None:
self.__raw_order_book[symbol] = {"bids": OrderedDict(), "asks": OrderedDict()}
SYMBOLS = ["tLTCBTC", "tETHUSD", "tETHBTC"]
raw_order_book = RawOrderBook(symbols=SYMBOLS)
bfx = Client()
@bfx.wss.on("open")
async def on_open():
for symbol in SYMBOLS:
await bfx.wss.subscribe("book", symbol=symbol, prec="R0")
@bfx.wss.on("subscribed")
def on_subscribed(subscription):
print(f"Subscription successful for symbol <{subscription['symbol']}>")
@bfx.wss.on("t_raw_book_snapshot")
def on_t_raw_book_snapshot(subscription: Book, snapshot: List[TradingPairRawBook]):
for data in snapshot:
raw_order_book.update(subscription["symbol"], data)
@bfx.wss.on("t_raw_book_update")
def on_t_raw_book_update(subscription: Book, data: TradingPairRawBook):
raw_order_book.update(subscription["symbol"], data)
@bfx.wss.on("checksum")
async def on_checksum(subscription: Book, value: int):
symbol = subscription["symbol"]
if raw_order_book.is_verifiable(symbol):
if not raw_order_book.verify(symbol, value):
print(
"Mismatch between local and remote checksums: "
f"restarting book for symbol <{symbol}>..."
)
_subscription = cast(Dict[str, Any], subscription.copy())
await bfx.wss.unsubscribe(sub_id=_subscription.pop("sub_id"))
await bfx.wss.subscribe(**_subscription)
raw_order_book.clear(symbol)
bfx.wss.run()