C++ UA_Client_Service_read 只产生空响应

我正在try 用C语言创建一个小程序，它将使用Open62541库通过OPC/UA连接轮询一帧数据，并将其转发到Kafka服务器.

当分别从 node 获取值时，一切工作正常，但我想使用UA_ReadRequest键.问题是，我只收到了空洞的回应.

OPC/UA服务器是使用freopc包在Python中编写的.

下面的函数try 使用UA_ReadResponse来获取指定 node ID的几个值:

void retrieveOPCData(void)
{
    UA_ReadRequest request;
    UA_ReadRequest_init(&request);
    UA_ReadValueId ids[nodeCount];
    
    for (int i = 0; i < nodeCount; i++)
    {
        UA_ReadValueId_init(&ids[i]);
        ids[i].attributeId = UA_ATTRIBUTEID_VALUE;
        ids[i].nodeId = nodesToRead[i];
    }

    request.nodesToRead = ids;

    for (int i = 0; i < nodeCount; i++)
    {
        UA_LOG_INFO(UA_Log_Stdout, UA_LOGCATEGORY_USERLAND, "ID%i: %s, %i", i,
            request.nodesToRead[i].nodeId.identifier.string.data,
            request.nodesToRead[i].nodeId.namespaceIndex);
    }

    UA_ReadResponse response = UA_Client_Service_read(client, request);

    UA_LOG_INFO(UA_Log_Stdout, UA_LOGCATEGORY_USERLAND, "Status: %i",
        response.responseHeader.serviceResult);
    UA_LOG_INFO(UA_Log_Stdout, UA_LOGCATEGORY_USERLAND, "Responses: %li", response.resultsSize);
}

结果值为UA_STATUSCODE_GOOD，但响应数量为0.在一个接一个地获取值时，它可以很好地工作，如下所示:

void readNodeAtIndex(int index)
{
    if (index >= nodeCount)
    {
        UA_LOG_INFO(UA_Log_Stdout, UA_LOGCATEGORY_USERLAND, "Index out of Range");
        return;
    }

    UA_Variant variant;
    UA_Variant_init(&variant);

    const UA_NodeId nodeId = nodesToRead[index];

    UA_StatusCode retval = UA_Client_readValueAttribute(client, nodeId, &variant);

    if (retval == UA_STATUSCODE_GOOD && UA_Variant_hasScalarType(&variant,
        &UA_TYPES[UA_TYPES_DOUBLE]))
    {
        UA_Double value = *(UA_Double*)variant.data;

        UA_LOG_INFO(UA_Log_Stdout, UA_LOGCATEGORY_USERLAND, "Double-Value: %f", value);
    }
    else if (retval == UA_STATUSCODE_GOOD && UA_Variant_hasScalarType(&variant,
        &UA_TYPES[UA_TYPES_BOOLEAN]))
    {
        UA_Boolean value = *(UA_Boolean*)variant.data;

        UA_LOG_INFO(UA_Log_Stdout, UA_LOGCATEGORY_USERLAND, "Boolean-Value: %i", value);
    }
    

    UA_Variant_clear(&variant);
}

OPC/UA服务器设置如下:

server = Server()
space_url = "opc.tcp://localhost:61032"
server.set_endpoint(space_url)
server.set_security_policy([ua.SecurityPolicyType.NoSecurity])
node = server.get_objects_node()