How should the signature parameter be generated for opening an authenticated connection to Coinbase Websocket? I can't find any concise description anywhere.
For GET/PUT
API calls, I successfully generated it with the below code, but with the Websocket there is neither a "method" nor a "path_url", so what should contain the "message"?
timestamp = str(time.time())
message = timestamp + request.method + request.path_url + (request.body or '')
hmac_key = base64.b64decode(self.secret_key)
signature = hmac.new(hmac_key, message.encode('utf-8'), hashlib.sha256)
signature_b64 = base64.b64encode(signature.digest())