如何从Bittrex调用该异步函数？WebSocket API升级求助

Hey there! I see you're transitioning from a scripted balance query to Bittrex's WebSocket API and got stuck on the signature and connection flow. Let's break this down step by step, starting with finishing that signature function and building out a complete working example.

First: Complete the Signature Function #

You had the right start with the HMAC-SHA512 signature—here's the full implementation:

async def create_signature(api_secret, challenge):
    # Sign the server-provided challenge string with your API secret
    api_sign = hmac.new(api_secret.encode(), challenge.encode(), hashlib.sha512)
    return api_sign.hexdigest()

This takes the unique challenge Bittrex sends you and signs it, which proves you own the API key/secret pair.

Full Working Example with Key Concepts Explained #

Here's a complete async script that handles connection, authentication, subscribing to balance updates, and parsing compressed messages:

from signalr_aio import Connection
from base64 import b64decode
from zlib import decompress, MAX_WBITS
import hashlib
import hmac
import json
import asyncio

async def create_signature(api_secret, challenge):
    api_sign = hmac.new(api_secret.encode(), challenge.encode(), hashlib.sha512)
    return api_sign.hexdigest()

async def main():
    # Bittrex's official WebSocket SignalR endpoint
    ws_url = "wss://socket-v3.bittrex.com/signalr"
    connection = Connection(ws_url, session=None)

    # Register the "c3" hub—this is Bittrex's v3 API hub for real-time data
    c3_hub = connection.register_hub("c3")

    # Handle incoming update messages (this is where you'll get balance data)
    async def handle_updates(message):
        # Bittrex compresses all update payloads with zlib + base64
        if message.get("M") == "update":
            compressed_payload = message["A"][0]
            # Decode base64, then decompress (MAX_WBITS |16 handles gzip-formatted compression)
            decompressed_data = decompress(b64decode(compressed_payload), MAX_WBITS | 16)
            parsed_data = json.loads(decompressed_data.decode())
            
            # Filter for balance-specific updates
            if parsed_data["type"] == "balance":
                print("\n--- Current Balance Update ---")
                for balance in parsed_data["data"]:
                    print(f"Asset: {balance['currencySymbol']}")
                    print(f"  Available: {balance['available']}")
                    print(f"  Total: {balance['total']}\n")

    # Attach the update handler to the hub
    c3_hub.on("update", handle_updates)

    # Handle the authentication challenge from Bittrex
    async def handle_challenge(message):
        challenge_str = message["A"][0]
        # Replace these with your actual Bittrex API credentials
        YOUR_API_KEY = "your-bittrex-api-key-here"
        YOUR_API_SECRET = "your-bittrex-api-secret-here"

        # Generate the required signature
        auth_signature = await create_signature(YOUR_API_SECRET, challenge_str)
        # Send authentication to the hub
        await c3_hub.invoke("authenticate", YOUR_API_KEY, auth_signature)
        print("Successfully authenticated with Bittrex WebSocket API!")

    # Attach the challenge handler
    c3_hub.on("challenge", handle_challenge)

    # Start the WebSocket connection
    await connection.start()

    # Subscribe to the "balance" channel to receive balance updates
    await c3_hub.invoke("subscribe", ["balance"])

    # Keep the connection running (prevent script from exiting)
    while True:
        await asyncio.sleep(1)

if __name__ == "__main__":
    event_loop = asyncio.get_event_loop()
    try:
        event_loop.run_until_complete(main())
    except KeyboardInterrupt:
        print("\nConnection closed manually.")

Key Concepts You Might Have Missed #

Let's clarify the parts that often trip people up:

• SignalR Hubs: Bittrex uses SignalR (a real-time communication framework) instead of raw WebSockets. The c3 hub is the official entry point for their v3 API—you can't connect to the right data without registering it.
• Challenge Authentication: Bittrex doesn't let you send credentials directly. Instead, it sends a unique challenge string, you sign it with your secret, and send back the signature. This prevents replay attacks.
• Message Compression: All real-time updates are compressed to save bandwidth. You must decode the base64 string first, then decompress it with zlib (the MAX_WBITS |16 flag handles the gzip header Bittrex uses).
• Subscriptions: You only get data for channels you explicitly subscribe to. For balances, we use the balance channel—other common channels are order (for your order updates) and market (for market price data).

Important Notes #

• Permissions: Make sure your Bittrex API key has read-only access (or full access if you need it) for balance data. You can set this when creating the key in your Bittrex account settings.
• Dependencies: Install the required library with pip install signalr-aio.
• Error Handling: Add try/except blocks around connection starts, invoke calls, and message parsing to handle disconnections or malformed data (critical for production use).

内容的提问来源于stack exchange，提问作者user9375283