java - 使用 java-websocket 库连接到 coinbase exchange websocket 流时，Draft 拒绝握手

Question

我正在尝试使用 Java-Websocket library by TooTallNate创建一个从 coinbase exchange websocket stream 接收消息的 websocket 客户端.由于 Python 中的并行化瓶颈，我正在将我用 Python 编写的程序移植到 Java，据我所知，我在 Java 中做的事情与在 Python 中做的一样。这是我使用 this websocket lib 在 Python 中打开连接的代码(这按预期工作):

ws = websocket.create_connection("wss://ws-feed.exchange.coinbase.com", 20)
            ws.send(json.dumps({
            "type": "subscribe",
            "product_id": "BTC-USD"
        }))

这是我的整个 Java 类:

public class CoinbaseWebsocketClient extends WebSocketClient {

private final Gson gson = new Gson();

private CoinbaseWebsocketClient(URI serverURI) {
    super(serverURI, new Draft_17());
    connect();
}

private static URI uri;
private static CoinbaseWebsocketClient coinbaseWebsocketClient;

static {
    try {
        uri = new URI("wss://ws-feed.exchange.coinbase.com");
    } catch (URISyntaxException e) {
        e.printStackTrace();
    }
}

protected static CoinbaseWebsocketClient get() {
    if (coinbaseWebsocketClient == null) {
        coinbaseWebsocketClient = new CoinbaseWebsocketClient(uri);
    }
    return coinbaseWebsocketClient;
}

@Override
public void onOpen(ServerHandshake serverHandshake) {
    System.out.println("Websocket open");
    final JsonObject btcUSD_Request = new JsonObject();
    btcUSD_Request.addProperty("type", "subscribe");
    btcUSD_Request.addProperty("product_id", "BTC_USD");
    final String requestString = gson.toJson(btcUSD_Request);
    send(requestString);
}

@Override
public void onMessage(String s) {
    System.out.println("Message received: " + s);
}

@Override
public void onClose(int code, String reason, boolean remote) {
    System.out.println("Websocket closed: " + reason);
}

@Override
public void onError(Exception e) {
    System.err.println("an error occurred:" + e);
}

我知道我的 Java 代码没有完全根本性的问题，因为当我使用 ws://echo.websocket.org 而不是 wss://ws-feed.exchange.coinbase 作为 URI 时，它按预期工作.com。但是，当我尝试连接到 wss://ws-feed.exchange.coinbase.com 时，出现此错误:

Websocket closed: draft org.java_websocket.drafts.Draft_17@7ca2fefb refuses handshake

据我所知，这个连接没有身份验证或类似的东西(我没有在我的 Python 程序中提供任何东西)所以我不知道这个错误的来源是什么。

Answer 1

需要像下面这样创建 sslcontext。它跳过证书。我可以在没有证书的情况下成功建立连接

SSLContext sslContext = SSLContext.getInstance("SSL");

// set up a TrustManager that trusts everything
sslContext.init(null, new TrustManager[] { new X509TrustManager() {
            public X509Certificate[] getAcceptedIssuers() {
                    System.out.println("getAcceptedIssuers =============");
                    return null;
            }

            public void checkClientTrusted(X509Certificate[] certs,
                            String authType) {
                    System.out.println("checkClientTrusted =============");
            }

            public void checkServerTrusted(X509Certificate[] certs,
                            String authType) {
                    System.out.println("checkServerTrusted =============");
            }
} }, new SecureRandom());