Eclipse milo：尝试读取数据时会话关闭

Question

我有一个外部 OPC UA 服务器，我想从中读取数据。我使用用户名和密码认证，所以我的客户端初始化如下：

public class MyClient {

    // ...

    public MyClient() throws Exception {
        EndpointDescription[] endpoints =
            UaTcpStackClient.getEndpoints(OPCConstants.OPC_SERVER_URI).get();

        // using the first endpoint
        EndpointDescription endpoint = endpoints[0];

        // client configuration
        OpcUaClientConfig config = OpcUaClientConfig.builder()
            .setApplicationName(LocalizedText.english("Example Client"))
            .setApplicationUri(String.format("some:example-client:%s",
                    UUID.randomUUID()))
            .setIdentityProvider(new UsernameProvider(USERNAME, PWD))
            .setEndpoint(endpoint)
            .build();
    }
}

客户的要求如下：

public CompletableFuture<DataValue> getData(NodeId nodeId) {
    LOGGER.debug("Sending request");
    return client.readValue(60000000.0, TimestampsToReturn.Server, nodeId);
}

我在初始化客户端并将其连接到服务器后从 main 方法调用此请求：

MyClient client = new MyClient();

NodeId requestedData = new NodeId(DATA_ID, DATA_KEY);
LOGGER.info("Sending synchronous TestStackRequest NodeId={}",
       requestedData);
client.connect();
DataValue response = client.getData(requestedData).get();
LOGGER.info("Received response value={}", response.getValue());
client.disconnect();

但是，此代码不起作用（尝试从服务器读取信息时会话已关闭）。我得到以下输出：

2018-04-12 17:43:27,765 DEBUG --- [ua-netty-event-loop-0] Recycler : -Dio.netty.recycler.maxCapacity.default: 262144
2018-04-12 17:43:27,777 DEBUG --- [ua-netty-event-loop-0] UaTcpClientAcknowledgeHandler : Sent Hello message on channel=[id: 0xfd9519e3, L:/172.20.100.54:55805 - R:/172.20.100.135:4840].
2018-04-12 17:43:27,786 DEBUG --- [ua-netty-event-loop-0] UaTcpClientAcknowledgeHandler : Received Acknowledge message on channel=[id: 0xfd9519e3, L:/172.20.100.54:55805 - R:/172.20.100.135:4840].
2018-04-12 17:43:27,793 DEBUG --- [ua-netty-event-loop-0] UaTcpClientMessageHandler : OpenSecureChannel timeout scheduled for +5s
2018-04-12 17:43:27,946 DEBUG --- [ua-shared-pool-0] UaTcpClientMessageHandler : Sent OpenSecureChannelRequest (Issue, id=0, currentToken=-1, previousToken=-1).
2018-04-12 17:43:27,951 DEBUG --- [ua-netty-event-loop-0] UaTcpClientMessageHandler : OpenSecureChannel timeout canceled
2018-04-12 17:43:27,961 DEBUG --- [ua-shared-pool-0] UaTcpClientMessageHandler : Received OpenSecureChannelResponse.
2018-04-12 17:43:27,967 DEBUG --- [ua-shared-pool-0] UaTcpClientMessageHandler : SecureChannel id=1698234671, currentTokenId=1, previousTokenId=-1, lifetime=3600000ms, createdAt=DateTime{utcTime=131680285857690000, javaDate=Thu Apr 12 19:43:05 CEST 2018}
2018-04-12 17:43:27,968 DEBUG --- [ua-netty-event-loop-0] UaTcpClientMessageHandler : 0 message(s) queued before handshake completed; sending now.
2018-04-12 17:43:27,968 DEBUG --- [ua-shared-pool-1] ClientChannelManager : Channel bootstrap succeeded: localAddress=/172.20.100.54:55805, remoteAddress=/172.20.100.135:4840
2018-04-12 17:43:27,996 DEBUG --- [ua-shared-pool-0] ClientChannelManager : disconnect(), currentState=Connected
2018-04-12 17:43:27,997 DEBUG --- [ua-shared-pool-1] ClientChannelManager : Sending CloseSecureChannelRequest...
2018-04-12 17:43:28,000 DEBUG --- [ua-netty-event-loop-0] ClientChannelManager : channelInactive(), disconnect complete
2018-04-12 17:43:28,001 DEBUG --- [ua-netty-event-loop-0] ClientChannelManager : disconnect complete, state set to Idle
2018-04-12 17:43:28,011 INFO --- [main] OpcUaClient : Eclipse Milo OPC UA Stack version: 0.2.1
2018-04-12 17:43:28,011 INFO --- [main] OpcUaClient : Eclipse Milo OPC UA Client SDK version: 0.2.1
2018-04-12 17:43:28,056 DEBUG --- [main] OpcUaClient : Added ServiceFaultListener: org.eclipse.milo.opcua.sdk.client.session.SessionFsm$FaultListener@46d59067
2018-04-12 17:43:28,066 DEBUG --- [main] OpcUaClient : Added SessionActivityListener: org.eclipse.milo.opcua.sdk.client.subscriptions.OpcUaSubscriptionManager@78452606
2018-04-12 17:43:28,189 INFO --- [main] CommunicationMain : Sending synchronous TestStackRequest NodeId=NodeId{ns=6, id=::opcua:opcData.outGoing.basic.cycleStep}
2018-04-12 17:43:28,189 DEBUG --- [main] ClientChannelManager : connect(), currentState=NotConnected
2018-04-12 17:43:28,190 DEBUG --- [main] ClientChannelManager : connect() while NotConnected
java.lang.Exception
at org.eclipse.milo.opcua.stack.client.ClientChannelManager.connect(ClientChannelManager.java:67)
at org.eclipse.milo.opcua.stack.client.UaTcpStackClient.connect(UaTcpStackClient.java:127)
at org.eclipse.milo.opcua.sdk.client.OpcUaClient.connect(OpcUaClient.java:313)
at com.mycompany.opcua.participants.MyClient.connect(MyClient.java:147)
at com.mycompany.opcua.participants.CommunicationMain.testClient(CommunicationMain.java:69)
at com.mycompany.opcua.participants.CommunicationMain.main(CommunicationMain.java:51)
2018-04-12 17:43:28,190 DEBUG --- [main] MyClient : Sending request
2018-04-12 17:43:28,197 DEBUG --- [ua-netty-event-loop-1] UaTcpClientAcknowledgeHandler : Sent Hello message on channel=[id: 0xd9b3f832, L:/172.20.100.54:55806 - R:/172.20.100.135:4840].
2018-04-12 17:43:28,204 DEBUG --- [ua-netty-event-loop-1] UaTcpClientAcknowledgeHandler : Received Acknowledge message on channel=[id: 0xd9b3f832, L:/172.20.100.54:55806 - R:/172.20.100.135:4840].
2018-04-12 17:43:28,205 DEBUG --- [ua-netty-event-loop-1] UaTcpClientMessageHandler : OpenSecureChannel timeout scheduled for +5s
2018-04-12 17:43:28,205 DEBUG --- [ua-shared-pool-0] UaTcpClientMessageHandler : Sent OpenSecureChannelRequest (Issue, id=0, currentToken=-1, previousToken=-1).
2018-04-12 17:43:28,208 DEBUG --- [ua-netty-event-loop-1] UaTcpClientMessageHandler : OpenSecureChannel timeout canceled
2018-04-12 17:43:28,208 DEBUG --- [ua-shared-pool-0] UaTcpClientMessageHandler : Received OpenSecureChannelResponse.
2018-04-12 17:43:28,209 DEBUG --- [ua-shared-pool-0] UaTcpClientMessageHandler : SecureChannel id=1698234672, currentTokenId=1, previousTokenId=-1, lifetime=3600000ms, createdAt=DateTime{utcTime=131680285860260000, javaDate=Thu Apr 12 19:43:06 CEST 2018}
2018-04-12 17:43:28,209 DEBUG --- [ua-netty-event-loop-1] UaTcpClientMessageHandler : 0 message(s) queued before handshake completed; sending now.
2018-04-12 17:43:28,209 DEBUG --- [ua-shared-pool-1] ClientChannelManager : Channel bootstrap succeeded: localAddress=/172.20.100.54:55806, remoteAddress=/172.20.100.135:4840
2018-04-12 17:43:28,210 DEBUG --- [ua-shared-pool-0] SessionFsm : S(Inactive) x E(CreateSessionEvent) = S'(Creating)
Exception in thread "main" java.util.concurrent.ExecutionException: UaException: status=Bad_SessionClosed, message=The session was closed by the client.
at java.base/java.util.concurrent.CompletableFuture.reportGet(CompletableFuture.java:395)2018-04-12 17:43:28,212 DEBUG --- [ua-shared-pool-1] SessionFsm : Sending CreateSessionRequest...

at java.base/java.util.concurrent.CompletableFuture.get(CompletableFuture.java:1999)
at com.mycompany.opcua.participants.CommunicationMain.testClient(CommunicationMain.java:70)
at com.mycompany.opcua.participants.CommunicationMain.main(CommunicationMain.java:51)
Caused by: UaException: status=Bad_SessionClosed, message=The session was closed by the client.
at org.eclipse.milo.opcua.stack.core.util.FutureUtils.failedUaFuture(FutureUtils.java:100)
at org.eclipse.milo.opcua.stack.core.util.FutureUtils.failedUaFuture(FutureUtils.java:88)
at org.eclipse.milo.opcua.sdk.client.session.states.Inactive.(Inactive.java:28)
at org.eclipse.milo.opcua.sdk.client.session.SessionFsm.(SessionFsm.java:69)
at org.eclipse.milo.opcua.sdk.client.OpcUaClient.(OpcUaClient.java:159)2018-04-12 17:43:28,212 INFO --- [NonceUtilSecureRandom] NonceUtil : SecureRandom seeded in 0ms.

at com.mycompany.opcua.participants.MyClient.(MyClient.java:112)
at com.mycompany.opcua.participants.CommunicationMain.testClient(CommunicationMain.java:60)
... 1 more

我使用 Eclipse milo 0.2.1 作为 OPC UA 库。

你能告诉我帽子会导致这个问题吗？如何解决？它可能是与 this 相关的竞争条件吗？

我可以使用其他客户端 (UaExpert) 连接到同一服务器。

提前致谢。

Answer 1

您正在进行的所有调用（connect()、disconnect() 和 readValues()）都是异步的，所以这里可能发生的情况是您在尝试时未连接阅读。

在进行下一步之前，请确保您为这些示例屏蔽了结果。（你没有在 connect() 上这样做）

Eclipse milo：尝试读取数据时会话关闭

Eclipse milo: Session closed when trying to read data

java

opc-ua

milo