| /* |
| * 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.metadata.etcd; |
| |
| import static org.apache.bookkeeper.metadata.etcd.EtcdUtils.msResult; |
| |
| import com.google.common.util.concurrent.ThreadFactoryBuilder; |
| |
| import io.etcd.jetcd.Lease; |
| import io.etcd.jetcd.lease.LeaseKeepAliveResponse; |
| import io.etcd.jetcd.support.CloseableClient; |
| |
| import io.grpc.stub.StreamObserver; |
| |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.Future; |
| import java.util.concurrent.ScheduledExecutorService; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.TimeoutException; |
| import java.util.function.Supplier; |
| |
| import lombok.AccessLevel; |
| import lombok.Getter; |
| import lombok.extern.slf4j.Slf4j; |
| import org.apache.bookkeeper.bookie.BookieException.MetadataStoreException; |
| import org.apache.bookkeeper.common.concurrent.FutureUtils; |
| import org.apache.bookkeeper.discover.RegistrationManager.RegistrationListener; |
| |
| /** |
| * Register to register a bookie in Etcd. |
| */ |
| @Slf4j |
| class EtcdBookieRegister implements AutoCloseable, Runnable, Supplier<Long> { |
| |
| private final Lease leaseClient; |
| private final long ttlSeconds; |
| private final ScheduledExecutorService executor; |
| private final RegistrationListener regListener; |
| private volatile CompletableFuture<Long> leaseFuture = new CompletableFuture<>(); |
| private volatile CompletableFuture<Void> keepAliveFuture = new CompletableFuture<>(); |
| |
| @Getter(AccessLevel.PACKAGE) |
| private volatile long leaseId = -0xabcd; |
| private volatile CloseableClient kaListener = null; |
| private volatile boolean running = true; |
| private long nextWaitTimeMs = 200; |
| private Future<?> runFuture = null; |
| |
| EtcdBookieRegister(Lease leaseClient, |
| long ttlSeconds, |
| RegistrationListener regListener) { |
| this.regListener = regListener; |
| this.leaseClient = leaseClient; |
| this.ttlSeconds = ttlSeconds; |
| this.executor = Executors.newSingleThreadScheduledExecutor( |
| new ThreadFactoryBuilder() |
| .setNameFormat("bookie-etcd-keepalive-thread") |
| .build()); |
| } |
| |
| long getTtlSeconds() { |
| return ttlSeconds; |
| } |
| |
| public synchronized EtcdBookieRegister start() { |
| if (null == runFuture) { |
| runFuture = executor.submit(this); |
| } |
| return this; |
| } |
| |
| private void newLeaseIfNeeded() throws MetadataStoreException { |
| boolean newLeaseNeeded; |
| synchronized (this) { |
| newLeaseNeeded = !leaseFuture.isDone(); |
| } |
| if (newLeaseNeeded) { |
| long leaseId = msResult(leaseClient.grant(ttlSeconds)).getID(); |
| keepAliveFuture = new CompletableFuture<>(); |
| if (kaListener != null) { |
| synchronized (this) { |
| kaListener.close(); |
| kaListener = null; |
| } |
| } |
| this.kaListener = leaseClient.keepAlive(leaseId, new StreamObserver<LeaseKeepAliveResponse>() { |
| @Override |
| public void onNext(LeaseKeepAliveResponse response) { |
| log.info("KeepAlive response : lease = {}, ttl = {}", |
| response.getID(), response.getTTL()); |
| } |
| |
| @Override |
| public void onError(Throwable t) { |
| log.info("KeepAlive renewal failed, leaseId {}", leaseId, t.fillInStackTrace()); |
| keepAliveFuture.completeExceptionally(t); |
| } |
| |
| @Override |
| public void onCompleted() { |
| log.info("{} lease completed! leaseId {}", leaseId); |
| keepAliveFuture.cancel(true); |
| } |
| }); |
| |
| this.leaseId = leaseId; |
| leaseFuture.complete(leaseId); |
| log.info("New lease '{}' is granted.", leaseId); |
| } |
| } |
| |
| private void waitForNewLeaseId() { |
| while (running) { |
| try { |
| newLeaseIfNeeded(); |
| nextWaitTimeMs = 100L; |
| } catch (MetadataStoreException e) { |
| log.error("Failed to grant a new lease for leaseId", leaseId, e); |
| try { |
| TimeUnit.MILLISECONDS.sleep(nextWaitTimeMs); |
| nextWaitTimeMs *= 2; |
| nextWaitTimeMs = Math.min(nextWaitTimeMs, TimeUnit.SECONDS.toMillis(ttlSeconds)); |
| } catch (InterruptedException e1) { |
| Thread.currentThread().interrupt(); |
| log.warn("Interrupted at backing off granting a new lease for leaseId {}", leaseId); |
| } |
| continue; |
| } |
| } |
| } |
| |
| @Override |
| public void run() { |
| while (running) { |
| waitForNewLeaseId(); |
| // here we get a lease, keep it alive |
| try { |
| log.info("Keeping Alive at lease = {}", get()); |
| keepAliveFuture.get(); |
| continue; |
| } catch (InterruptedException ie) { |
| Thread.currentThread().interrupt(); |
| log.warn("Interrupted at keeping lease '{}' alive", leaseId); |
| resetLease(); |
| } catch (ExecutionException ee) { |
| log.warn("Failed to keep alive lease '{}'", leaseId, ee); |
| resetLease(); |
| } |
| } |
| } |
| |
| private void resetLease() { |
| synchronized (this) { |
| leaseFuture = new CompletableFuture<>(); |
| } |
| if (null != regListener) { |
| regListener.onRegistrationExpired(); |
| } |
| } |
| |
| @Override |
| public void close() { |
| synchronized (this) { |
| if (!running) { |
| return; |
| } else { |
| running = false; |
| } |
| if (null != runFuture) { |
| if (runFuture.cancel(true)) { |
| log.info("Successfully interrupted bookie register."); |
| } |
| } |
| keepAliveFuture.cancel(true); |
| if (kaListener != null) { |
| kaListener.close(); |
| kaListener = null; |
| } |
| } |
| CompletableFuture<Void> closeFuture = new CompletableFuture<>(); |
| executor.submit(() -> { |
| FutureUtils.complete(closeFuture, (Void) null); |
| }); |
| closeFuture.join(); |
| } |
| |
| @Override |
| public Long get() { |
| while (true) { |
| try { |
| return leaseFuture.get(100, TimeUnit.MILLISECONDS); |
| } catch (InterruptedException e) { |
| log.warn("Interrupted at getting lease id", e); |
| return -1L; |
| } catch (ExecutionException e) { |
| throw new IllegalArgumentException("Should never reach here"); |
| } catch (TimeoutException e) { |
| continue; |
| } |
| |
| } |
| } |
| |
| } |