如何获取Upbit动态WebSocket URL？连接失效及JS函数排查求助

Hey there, let's dig into this Upbit WebSocket issue you're facing. That dynamic URL you're seeing is almost certainly tied to a short-lived session token or auth parameter—hence why it only works once. Here's how to unpack and solve this:

1. Trace the n parameter with browser dev tools #

The thousands of n() functions are confusing, but you can zero in on the exact one being used here:

• Open your browser's DevTools, navigate to the Sources tab, and find the vender-bundle-03c1ef05e3ad23870adb.js file.
• Set a breakpoint on the line this.ws = new u(this.url, [], n). When the code hits this breakpoint, hover over n to see what it contains. Is it a string, an object with headers, or a function result?
• Look at the surrounding code context: What variables are being passed to this specific n? Does it reference cookies, localStorage entries, or tokens fetched from an API? Upbit likely injects session-specific data here to validate the WebSocket connection.

2. Capture the full WebSocket handshake details #

Your browser's Network tab will reveal critical clues about the valid connection:

• Filter the Network tab by "WS" (WebSocket) and refresh the Upbit exchange page.
• Click on the active WebSocket connection entry, then check the Headers tab:
  • Note the full dynamic URL (look for query parameters or path segments that change on each load—this is your one-time token).
  • Inspect request headers like Cookie, Sec-WebSocket-Protocol, or Origin—these often contain session validation data required for the connection.

3. Identify how the dynamic token is generated #

Once you spot the unique token in the URL or headers:

• Search the page's JavaScript code for keywords matching the token format (e.g., alphanumeric strings, JWT patterns).
• Check if the token is fetched via a hidden API call (look for XHR/fetch requests in the Network tab that load before the WebSocket connects). Upbit might expose an endpoint that generates these one-time WebSocket tokens for active sessions.

4. Replicate the session context in your connection #

To reuse the WebSocket successfully:

• If the token comes from an API call, replicate that request in your code (include all necessary cookies or auth headers from the browser session).
• Ensure your WebSocket client sends the same Origin header and cookies that the browser uses—Upbit likely blocks connections that don't match a valid session context.

Example Workflow #

Here's a rough step-by-step to implement:

1. Load the Upbit exchange page, capture the valid WebSocket URL and associated cookies/tokens.
2. Locate the API endpoint that generates the dynamic token (e.g., a GET request to /api/v1/websocket/session).
3. In your code, first call this endpoint with the required session cookies to fetch a fresh token.
4. Construct the WebSocket URL using the new token and initiate the connection with matching headers.

Content of the question is from Stack Exchange, asked by soulmachine