AwsIotWebSocketUrlSigner我正在尝试使用 Eclipse Paho 创建一个 Java Mqtt 客户端，该客户端可以使用使用'sgetSignedUrl方法生成的 SigV4 预签名 URL 连接到 AWS IoT MessageBroker 。此连接将使用基于 Websockets 的 MQTT，并具有以“wss://”开头的 URL 语法。
连接代码如下所示。
IMqttAsyncClient client = new MqttAsyncClient(*presignedUrl*,MqttAsyncClient.generateClientId(), new MemoryPersistence());
MqttConnectOptions options = new MqttConnectOptions();
options.setCleanSession(true);
IMqttToken token = client.connect(options);
token.waitForCompletion();
client.setCallback( *callBackObject* );
client.subscribe(topic, AWSIotQos.QOS1.getValue());
我一直低于异常。它在上面的 connect() 处失败。
MqttException (0) - java.lang.NullPointerException
at org.eclipse.paho.client.mqttv3.internal.ExceptionHelper.createMqttException(ExceptionHelper.java:38)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:664)
at java.lang.Thread.run(Thread.java:749)
Caused by: java.lang.NullPointerException
at org.eclipse.paho.client.mqttv3.internal.websocket.WebSocketHandshake.receiveHandshakeResponse(WebSocketHandshake.java:133)
at org.eclipse.paho.client.mqttv3.internal.websocket.WebSocketHandshake.execute(WebSocketHandshake.java:74)
at org.eclipse.paho.client.mqttv3.internal.websocket.WebSocketSecureNetworkModule.start(WebSocketSecureNetworkModule.java:77)
at org.eclipse.paho.client.mqttv3.internal.ClientComms$ConnectBG.run(ClientComms.java:650)
在 Eclipse Paho 中，验证 WSS 握手时发生代码异常。
String connectionHeader = (String) headerMap.get(HTTP_HEADER_CONNECTION);
if (connectionHeader == null || connectionHeader.equalsIgnoreCase(HTTP_HEADER_CONNECTION_VALUE)) {
throw new IOException("WebSocket Response header: Incorrect connection header");
}
我可以使用 Javascript 客户端和 presignedUrl 进行连接。
任何帮助/示例代码将不胜感激。