| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| package org.apache.bookkeeper.grpc.resolver; |
| |
| import static com.google.common.base.Preconditions.checkState; |
| |
| import com.google.common.util.concurrent.ThreadFactoryBuilder; |
| import io.grpc.Attributes; |
| import io.grpc.EquivalentAddressGroup; |
| import io.grpc.NameResolver; |
| import java.net.URI; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.Objects; |
| import java.util.Optional; |
| import java.util.Set; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.ScheduledExecutorService; |
| import java.util.stream.Collectors; |
| import org.apache.bookkeeper.conf.ClientConfiguration; |
| import org.apache.bookkeeper.meta.MetadataClientDriver; |
| import org.apache.bookkeeper.meta.exceptions.MetadataException; |
| import org.apache.bookkeeper.net.BookieSocketAddress; |
| import org.apache.bookkeeper.stats.NullStatsLogger; |
| |
| /** |
| * A {@link NameResolver} implementation based on bookkeeper {@link org.apache.bookkeeper.discover.RegistrationClient}. |
| */ |
| class BKRegistrationNameResolver extends NameResolver { |
| |
| private final MetadataClientDriver clientDriver; |
| private final URI serviceURI; |
| private final ScheduledExecutorService executor; |
| |
| private Listener listener; |
| private boolean shutdown; |
| private boolean resolving; |
| |
| BKRegistrationNameResolver(MetadataClientDriver clientDriver, |
| URI serviceURI) { |
| this.clientDriver = clientDriver; |
| this.serviceURI = serviceURI; |
| this.executor = Executors.newSingleThreadScheduledExecutor( |
| new ThreadFactoryBuilder().setNameFormat("registration-name-resolver").build()); |
| } |
| |
| @Override |
| public String getServiceAuthority() { |
| return serviceURI.getAuthority(); |
| } |
| |
| @Override |
| public synchronized void start(Listener listener) { |
| checkState(null == this.listener, "Resolver already started"); |
| this.listener = Objects.requireNonNull(listener, "Listener is null"); |
| |
| ClientConfiguration conf = new ClientConfiguration(); |
| conf.setMetadataServiceUri(serviceURI.toString()); |
| |
| try { |
| clientDriver.initialize(conf, executor, NullStatsLogger.INSTANCE, Optional.empty()); |
| } catch (MetadataException e) { |
| throw new RuntimeException("Failed to initialize registration client driver at " + serviceURI, e); |
| } |
| |
| resolve(); |
| } |
| |
| private synchronized void resolve() { |
| if (resolving || shutdown) { |
| return; |
| } |
| resolving = true; |
| this.clientDriver.getRegistrationClient().watchWritableBookies(bookies -> { |
| Listener savedListener; |
| synchronized (this) { |
| savedListener = listener; |
| } |
| savedListener.onAddresses( |
| hostsToEquivalentAddressGroups(bookies.getValue()), |
| Attributes.EMPTY |
| ); |
| }).whenComplete((ignored, cause) -> { |
| try { |
| if (null != cause) { |
| resolve(); |
| } |
| } finally { |
| synchronized (this) { |
| resolving = false; |
| } |
| } |
| }); |
| } |
| |
| private static List<EquivalentAddressGroup> hostsToEquivalentAddressGroups(Set<BookieSocketAddress> bookies) { |
| return bookies.stream() |
| .map(addr -> new EquivalentAddressGroup( |
| Collections.singletonList(addr.getSocketAddress()), |
| Attributes.EMPTY |
| )) |
| .collect(Collectors.toList()); |
| } |
| |
| @Override |
| public void shutdown() { |
| synchronized (this) { |
| if (shutdown) { |
| return; |
| } |
| shutdown = true; |
| } |
| executor.shutdown(); |
| clientDriver.close(); |
| } |
| } |