katstack commented on code in PR #4234: URL: https://github.com/apache/logging-log4j2/pull/4234#discussion_r4360905359
########## log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/action/internal/CompressActionSupport.java: ########## @@ -0,0 +1,131 @@ +/* + * 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.logging.log4j.core.appender.rolling.action.internal; + +import java.io.BufferedOutputStream; +import java.io.File; +import java.io.FileInputStream; +import java.io.FileOutputStream; +import java.io.IOException; +import java.io.OutputStream; +import java.util.Set; +import java.util.concurrent.ConcurrentHashMap; +import java.util.concurrent.ConcurrentMap; +import org.apache.logging.log4j.status.StatusLogger; + +/** Common file handling and compression-level resolution for compression actions. */ +public final class CompressActionSupport { + + private static final int BUF_SIZE = 8192; + private static final ConcurrentMap<String, Set<Integer>> WARNED_LEVELS = new ConcurrentHashMap<>(); + + private CompressActionSupport() {} + + /** + * Resolves a compression level during compression execution, reporting each unsupported format and configured + * level only once. + * + * @param format compression format + * @param level configured compression level + * @param minimum minimum supported level + * @param maximum maximum supported level + * @param defaultLevel format-specific default + * @return the configured level if supported, otherwise the default + */ + public static int resolveCompressionLevel( + final String format, final int level, final int minimum, final int maximum, final int defaultLevel) { + if (level >= minimum && level <= maximum) { + return level; + } + if (WARNED_LEVELS + .computeIfAbsent(format, key -> ConcurrentHashMap.newKeySet()) + .add(level)) { + StatusLogger.getLogger() + .warn("Unsupported {} compression level {}; using default level {}.", format, level, defaultLevel); + } + return defaultLevel; + } + + /** + * Compresses a source file while retaining it. + * + * @param source source file + * @param destination destination file + * @param compressorOutputStreamFactory factory for the compressor output stream + * @return {@code true} if the source file was compressed + * @throws IOException if an I/O error occurs + */ + public static boolean execute( + final File source, + final File destination, + final CompressorOutputStreamFactory compressorOutputStreamFactory) + throws IOException { + return execute(source, destination, false, compressorOutputStreamFactory); + } + + /** + * Compresses a source file. + * + * @param source source file + * @param destination destination file + * @param deleteSource whether to delete the source file after successful compression + * @param compressorOutputStreamFactory factory for the compressor output stream + * @return {@code true} if the source file was compressed + * @throws IOException if an I/O error occurs + */ + public static boolean execute( + final File source, + final File destination, + final boolean deleteSource, + final CompressorOutputStreamFactory compressorOutputStreamFactory) + throws IOException { + if (!source.exists()) { + return false; + } + try (final FileInputStream input = new FileInputStream(source); + final FileOutputStream fileOutput = new FileOutputStream(destination); + final OutputStream compressorOutput = compressorOutputStreamFactory.create(fileOutput); + final OutputStream output = new BufferedOutputStream(compressorOutput, BUF_SIZE)) { + final byte[] buffer = new byte[BUF_SIZE]; + int count; + while ((count = input.read(buffer)) != -1) { + output.write(buffer, 0, count); + } + } Review Comment: Agreed. I think it makes sense to address these file-handling improvements in a separate PR from the compression-level changes. -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
