virajjasani commented on code in PR #5418: URL: https://github.com/apache/hadoop/pull/5418#discussion_r1113830663
########## hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/util/AsyncRFAAppender.java: ########## @@ -0,0 +1,139 @@ +/** + * 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.hadoop.hdfs.util; + +import java.io.IOException; + +import org.apache.log4j.AsyncAppender; +import org.apache.log4j.PatternLayout; +import org.apache.log4j.RollingFileAppender; +import org.apache.log4j.spi.LoggingEvent; + +/** + * Until we migrate to log4j2, use this appender for namenode audit logger as well as + * datanode and namenode metric loggers with log4j1 properties. + * This appender will take parameters necessary to supply RollingFileAppender to AsyncAppender. + * While migrating to log4j2, we can directly specify appender ref to Async appender. + */ +public class AsyncRFAAppender extends AsyncAppender { Review Comment: With this patch, even though we have new custom appender, it's only temporary here. This solves two purposes: 1. When we migrate from log4j to log4j2 properties, we can directly use log4j2 Async appender and provide appender ref as other appenders (i.e. wrap RFA appender to Async appender). Hence, this custom appender no longer needs to be migrated to log4j2, rather we can remove it cleanly. 2. Before migrating to log4j2, we still have a way to wrap RFA in Async appender without touching the code. We can directly refer to this custom appender in log4j.properties (as done with this patch) -- 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: common-issues-unsubscr...@hadoop.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-issues-h...@hadoop.apache.org
