private void returnKeepAlive(ServiceRequest<PublishRequest, PublishResponse> service) {
ResponseHeader header = service.createResponseHeader();
UInteger sequenceNumber = uint(currentSequenceNumber());
NotificationMessage notificationMessage =
new NotificationMessage(sequenceNumber, DateTime.now(), new ExtensionObject[0]);
UInteger[] available = getAvailableSequenceNumbers();
UInteger requestHandle = service.getRequest().getRequestHeader().getRequestHandle();
StatusCode[] acknowledgeResults = subscriptionManager.getAcknowledgeResults(requestHandle);
PublishResponse response =
new PublishResponse(
header,
subscriptionId,
available,
moreNotifications,
notificationMessage,
acknowledgeResults,
new DiagnosticInfo[0]);
service.setResponse(response);
logger.debug(
"[id={}] returned keep-alive NotificationMessage sequenceNumber={}.",
subscriptionId,
sequenceNumber);
}
/**
* Query the GetEndpoints service at the given endpoint URL.
*
* @param endpointUrl the endpoint URL to get endpoints from.
* @return the {@link EndpointDescription}s returned by the GetEndpoints service.
*/
public static CompletableFuture<EndpointDescription[]> getEndpoints(String endpointUrl) {
UaTcpStackClientConfig config =
UaTcpStackClientConfig.builder().setEndpointUrl(endpointUrl).build();
UaTcpStackClient client = new UaTcpStackClient(config);
GetEndpointsRequest request =
new GetEndpointsRequest(
new RequestHeader(null, DateTime.now(), uint(1), uint(0), null, uint(5000), null),
endpointUrl,
null,
new String[] {Stack.UA_TCP_BINARY_TRANSPORT_URI});
return client
.<GetEndpointsResponse>sendRequest(request)
.whenComplete((r, ex) -> client.disconnect())
.thenApply(GetEndpointsResponse::getEndpoints);
}
/**
* Query the FindServers service at the given endpoint URL.
*
* <p>The endpoint URL(s) for each server {@link ApplicationDescription} returned can then be used
* in a {@link #getEndpoints(String)} call to discover the endpoints for that server.
*
* @param endpointUrl the endpoint URL to find servers at.
* @return the {@link ApplicationDescription}s returned by the FindServers service.
*/
public static CompletableFuture<ApplicationDescription[]> findServers(String endpointUrl) {
UaTcpStackClientConfig config =
UaTcpStackClientConfig.builder().setEndpointUrl(endpointUrl).build();
UaTcpStackClient client = new UaTcpStackClient(config);
FindServersRequest request =
new FindServersRequest(
new RequestHeader(null, DateTime.now(), uint(1), uint(0), null, uint(5000), null),
endpointUrl,
null,
null);
return client
.<FindServersResponse>sendRequest(request)
.whenComplete((r, ex) -> client.disconnect())
.thenApply(FindServersResponse::getServers);
}
