/**
* 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);
}
/**
* 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);
}
public static CompletableFuture<Channel> bootstrap(UaTcpStackClient client) {
CompletableFuture<Channel> handshake = new CompletableFuture<>();
Bootstrap bootstrap = new Bootstrap();
bootstrap
.group(Stack.sharedEventLoop())
.channel(NioSocketChannel.class)
.option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT)
.option(ChannelOption.TCP_NODELAY, true)
.handler(
new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel channel) throws Exception {
channel.pipeline().addLast(new UaTcpClientAcknowledgeHandler(client, handshake));
}
});
try {
URI uri = URI.create(client.getEndpointUrl());
bootstrap
.connect(uri.getHost(), uri.getPort())
.addListener(
(ChannelFuture f) -> {
if (!f.isSuccess()) {
handshake.completeExceptionally(f.cause());
}
});
} catch (Throwable t) {
UaException failure =
new UaException(
StatusCodes.Bad_TcpEndpointUrlInvalid,
"endpoint URL invalid: " + client.getEndpointUrl());
handshake.completeExceptionally(failure);
}
return handshake;
}
