jdeppe-pivotal commented on a change in pull request #7408: URL: https://github.com/apache/geode/pull/7408#discussion_r828551150
########## File path: geode-for-redis/src/main/java/org/apache/geode/redis/internal/eventing/BlockingCommandListener.java ########## @@ -0,0 +1,121 @@ +/* + * 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.geode.redis.internal.eventing; + +import java.util.Collections; +import java.util.List; +import java.util.concurrent.ScheduledExecutorService; +import java.util.concurrent.TimeUnit; +import java.util.concurrent.atomic.AtomicBoolean; + +import org.apache.geode.annotations.VisibleForTesting; +import org.apache.geode.redis.internal.commands.Command; +import org.apache.geode.redis.internal.commands.RedisCommandType; +import org.apache.geode.redis.internal.commands.executor.RedisResponse; +import org.apache.geode.redis.internal.data.RedisKey; +import org.apache.geode.redis.internal.netty.Coder; +import org.apache.geode.redis.internal.netty.ExecutionHandlerContext; + +public class BlockingCommandListener implements EventListener { + + private final ExecutionHandlerContext context; + private final Command command; + private final List<RedisKey> keys; + private final double timeoutSeconds; + private final long timeSubmitted; + private final AtomicBoolean active = new AtomicBoolean(true); + + /** + * Constructor to create an instance of a BlockingCommandListener in response to a blocking + * command. When receiving a relevant event, blocking commands simply resubmit the command + * into the Netty pipeline. + * + * @param context the associated ExecutionHandlerContext + * @param command the blocking command associated with this listener + * @param keys the list of keys the command is interested in + * @param timeoutSeconds the timeout for the command to block in seconds + */ + public BlockingCommandListener(ExecutionHandlerContext context, Command command, + List<RedisKey> keys, double timeoutSeconds) { + this.context = context; + this.command = command; + this.timeoutSeconds = timeoutSeconds; + this.keys = Collections.unmodifiableList(keys); + timeSubmitted = System.nanoTime(); + } + + @Override + public List<RedisKey> keys() { + return keys; + } + + @Override + public EventResponse process(RedisCommandType commandType, RedisKey key) { + if (!keys.contains(key)) { + return EventResponse.CONTINUE; + } + + if (active.compareAndSet(true, false)) { Review comment: I think it's a good idea. This also ensures that the timeout does not fully process when a listener is resubmitted. Since the scheduled timeouts are not being cancelled we will have some listeners hanging around until their timeouts fire. Do you think that's an issue? I could add a `cleanup()` call to the listener that is executed when the listener is removed. But it's probably not necessary at this point. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: notifications-unsubscr...@geode.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
