| /* |
| * Copyright 2015 Open Networking Laboratory |
| * |
| * Licensed 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.onosproject.store.consistent.impl; |
| |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.ScheduledExecutorService; |
| import java.util.concurrent.TimeUnit; |
| import java.util.function.BiFunction; |
| |
| import org.onosproject.store.service.AsyncAtomicCounter; |
| |
| |
| |
| |
| |
| import org.slf4j.Logger; |
| |
| import static com.google.common.base.Preconditions.*; |
| import static org.slf4j.LoggerFactory.getLogger; |
| |
| /** |
| * Default implementation for a distributed AsyncAtomicCounter backed by |
| * partitioned Raft DB. |
| * <p> |
| * The initial value will be zero. |
| */ |
| public class DefaultAsyncAtomicCounter implements AsyncAtomicCounter { |
| |
| private final String name; |
| private final Database database; |
| private final boolean retryOnFailure; |
| private final ScheduledExecutorService retryExecutor; |
| // TODO: configure delay via builder |
| private static final int DELAY_BETWEEN_RETRY_SEC = 1; |
| private final Logger log = getLogger(getClass()); |
| |
| public DefaultAsyncAtomicCounter(String name, |
| Database database, |
| boolean retryOnException, |
| ScheduledExecutorService retryExecutor) { |
| this.name = checkNotNull(name); |
| this.database = checkNotNull(database); |
| this.retryOnFailure = retryOnException; |
| this.retryExecutor = retryExecutor; |
| } |
| |
| @Override |
| public CompletableFuture<Long> incrementAndGet() { |
| return addAndGet(1L); |
| } |
| |
| @Override |
| public CompletableFuture<Long> get() { |
| return database.counterGet(name); |
| } |
| |
| @Override |
| public CompletableFuture<Long> getAndIncrement() { |
| return getAndAdd(1L); |
| } |
| |
| @Override |
| public CompletableFuture<Long> getAndAdd(long delta) { |
| CompletableFuture<Long> result = database.counterGetAndAdd(name, delta); |
| if (!retryOnFailure) { |
| return result; |
| } |
| |
| CompletableFuture<Long> future = new CompletableFuture<>(); |
| return result.whenComplete((r, e) -> { |
| if (e != null) { |
| log.warn("getAndAdd failed due to {}. Will retry", e.getMessage()); |
| retryExecutor.schedule(new RetryTask(database::counterGetAndAdd, delta, future), |
| DELAY_BETWEEN_RETRY_SEC, |
| TimeUnit.SECONDS); |
| } else { |
| future.complete(r); |
| } |
| }).thenCompose(v -> future); |
| } |
| |
| @Override |
| public CompletableFuture<Long> addAndGet(long delta) { |
| CompletableFuture<Long> result = database.counterAddAndGet(name, delta); |
| if (!retryOnFailure) { |
| return result; |
| } |
| |
| CompletableFuture<Long> future = new CompletableFuture<>(); |
| return result.whenComplete((r, e) -> { |
| if (e != null) { |
| log.warn("addAndGet failed due to {}. Will retry", e.getMessage()); |
| retryExecutor.schedule(new RetryTask(database::counterAddAndGet, delta, future), |
| DELAY_BETWEEN_RETRY_SEC, |
| TimeUnit.SECONDS); |
| } else { |
| future.complete(r); |
| } |
| }).thenCompose(v -> future); |
| } |
| |
| private class RetryTask implements Runnable { |
| |
| private final BiFunction<String, Long, CompletableFuture<Long>> function; |
| private final Long delta; |
| private final CompletableFuture<Long> result; |
| |
| public RetryTask(BiFunction<String, Long, CompletableFuture<Long>> function, |
| Long delta, |
| CompletableFuture<Long> result) { |
| this.function = function; |
| this.delta = delta; |
| this.result = result; |
| } |
| |
| @Override |
| public void run() { |
| function.apply(name, delta).whenComplete((r, e) -> { |
| if (e == null) { |
| result.complete(r); |
| } else { |
| log.warn("{} retry failed due to {}. Will try again...", function, e.getMessage()); |
| // TODO: Exponential backoff |
| // TODO: limit retries |
| retryExecutor.schedule(this, DELAY_BETWEEN_RETRY_SEC, TimeUnit.SECONDS); |
| } |
| }); |
| } |
| } |
| } |