| /* |
| * 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.clients.utils; |
| |
| import com.google.common.util.concurrent.FutureCallback; |
| import com.google.common.util.concurrent.Futures; |
| import com.google.common.util.concurrent.ListenableFuture; |
| import io.grpc.Status; |
| import io.grpc.StatusException; |
| import io.grpc.StatusRuntimeException; |
| import java.util.Iterator; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.ScheduledExecutorService; |
| import java.util.concurrent.TimeUnit; |
| import java.util.function.BiConsumer; |
| import lombok.extern.slf4j.Slf4j; |
| import org.apache.bookkeeper.clients.impl.channel.StorageServerChannel; |
| import org.apache.bookkeeper.clients.impl.container.StorageContainerChannel; |
| import org.apache.bookkeeper.common.concurrent.FutureUtils; |
| import org.apache.bookkeeper.common.util.Backoff.Policy; |
| |
| /** |
| * A process for processing rpc request on storage container channel. |
| */ |
| @Slf4j |
| public abstract class ListenableFutureRpcProcessor<RequestT, ResponseT, ResultT> |
| implements BiConsumer<StorageServerChannel, Throwable>, |
| FutureCallback<ResponseT>, |
| Runnable { |
| |
| private final StorageContainerChannel scChannel; |
| private final Iterator<Long> backoffs; |
| private final ScheduledExecutorService executor; |
| private final CompletableFuture<ResultT> resultFuture; |
| |
| private CompletableFuture<StorageServerChannel> serverChannelFuture = null; |
| |
| protected ListenableFutureRpcProcessor(StorageContainerChannel channel, |
| ScheduledExecutorService executor, |
| Policy backoffPolicy) { |
| this.scChannel = channel; |
| this.backoffs = backoffPolicy.toBackoffs().iterator(); |
| this.resultFuture = FutureUtils.createFuture(); |
| this.executor = executor; |
| } |
| |
| /** |
| * Create the rpc request for the processor. |
| * |
| * @return the created rpc request. |
| */ |
| protected abstract RequestT createRequest(); |
| |
| /** |
| * Get the RPC service from the server channel. |
| * |
| * @return rpc service. |
| */ |
| protected abstract ListenableFuture<ResponseT> sendRPC(StorageServerChannel rsChannel, RequestT requestT); |
| |
| /** |
| * Process the response and convert it back to a result. |
| * |
| * @param response response |
| * @return the converted result. |
| */ |
| protected abstract ResultT processResponse(ResponseT response) throws Exception; |
| |
| public CompletableFuture<ResultT> process() { |
| serverChannelFuture = scChannel.getStorageContainerChannelFuture(); |
| serverChannelFuture.whenCompleteAsync(this, executor); |
| return resultFuture; |
| } |
| |
| @Override |
| public void run() { |
| process(); |
| } |
| |
| /** |
| * Logic on handling channel exceptions. |
| * |
| * @param storageServerChannel server channel |
| * @param cause exception on establishing channel. |
| */ |
| @Override |
| public void accept(StorageServerChannel storageServerChannel, Throwable cause) { |
| if (null != cause) { |
| // The `StorageContainerChannel` already retry on failures related to server channel, |
| // So we don't need to retry here if failed to retrieve a channel to the server |
| // that hosts this storage container. |
| resultFuture.completeExceptionally(cause); |
| return; |
| } |
| |
| sendRpcToServerChannel(storageServerChannel); |
| } |
| |
| private void sendRpcToServerChannel(StorageServerChannel rsChannel) { |
| RequestT request; |
| try { |
| request = createRequest(); |
| } catch (Exception e) { |
| // fail to create request |
| resultFuture.completeExceptionally(e); |
| return; |
| } |
| |
| Futures.addCallback( |
| sendRPC(rsChannel, request), |
| this, |
| executor); |
| } |
| |
| @Override |
| public void onSuccess(ResponseT result) { |
| try { |
| resultFuture.complete(processResponse(result)); |
| } catch (Exception e) { |
| resultFuture.completeExceptionally(e); |
| } |
| } |
| |
| @Override |
| public void onFailure(Throwable t) { |
| Status status = null; |
| if (t instanceof StatusRuntimeException) { |
| status = ((StatusRuntimeException) t).getStatus(); |
| } else if (t instanceof StatusException) { |
| status = ((StatusException) t).getStatus(); |
| } |
| |
| if (Status.NOT_FOUND == status) { |
| // `NOT_FOUND` means storage container is not found. that means: |
| // |
| // - the container is moved to a different server |
| // - the container is not assigned to any servers yet |
| // - the container is assigned, but it is still starting up and not ready for serving |
| // |
| // at either case, we need to reset the storage server channel, so next retry can attempt to re-locate |
| // the storage container again |
| scChannel.resetStorageServerChannelFuture(serverChannelFuture); |
| } |
| |
| if (shouldRetryOn(status) && backoffs.hasNext()) { |
| long backoffMs = backoffs.next(); |
| executor.schedule(this, backoffMs, TimeUnit.MILLISECONDS); |
| } else { |
| resultFuture.completeExceptionally(t); |
| } |
| } |
| |
| protected boolean shouldRetryOn(Status statusCode) { |
| return Status.NOT_FOUND == statusCode; |
| } |
| } |