org.apache.gobblin.yarn.GobblinYarnLogSource.java Source code

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Here is the source code for org.apache.gobblin.yarn.GobblinYarnLogSource.java

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/*
 * 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.gobblin.yarn;

import java.io.IOException;
import java.net.URI;
import java.util.List;
import java.util.stream.Collectors;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.yarn.api.ApplicationConstants;
import org.apache.hadoop.yarn.api.records.ContainerId;

import com.google.common.base.Splitter;
import com.google.common.collect.ImmutableSet;
import com.google.common.io.Files;
import com.typesafe.config.Config;

import org.apache.gobblin.configuration.ConfigurationKeys;
import org.apache.gobblin.util.PathUtils;
import org.apache.gobblin.util.logs.LogCopier;

/**
 * A base class for container processes that are sources of Gobblin Yarn application logs.
 *
 * <p>
 *   The source log files are supposed to be on the local {@link FileSystem} and will
 *   be copied to a given destination {@link FileSystem}, which is typically HDFS.
 * </p>
 *
 * @author Yinan Li
 */
class GobblinYarnLogSource {
    private static final Splitter COMMA_SPLITTER = Splitter.on(',').omitEmptyStrings().trimResults();
    private static final Configuration AUTO_CLOSE_CONFIG = new Configuration();

    static {
        AUTO_CLOSE_CONFIG.setBoolean("fs.automatic.close", false);
    }

    /**
     * Return if the log source is present or not.
     *
     * @return {@code true} if the log source is present and {@code false} otherwise
     */
    protected boolean isLogSourcePresent() {
        return System.getenv().containsKey(ApplicationConstants.Environment.LOG_DIRS.toString());
    }

    /**
     * Build a {@link LogCopier} instance used to copy the logs out from this {@link GobblinYarnLogSource}.
     *
     * @param config the {@link Config} use to create the {@link LogCopier}
     * @param containerId the {@link ContainerId} of the container the {@link LogCopier} runs in
     * @param destFs the destination {@link FileSystem}
     * @param appWorkDir the Gobblin Yarn application working directory on HDFS
     * @return a {@link LogCopier} instance
     * @throws IOException if it fails on any IO operation
     */
    protected LogCopier buildLogCopier(Config config, String containerId, FileSystem destFs, Path appWorkDir)
            throws IOException {
        LogCopier.Builder builder = LogCopier.newBuilder().useSrcFileSystem(buildFileSystem(config, true))
                .useDestFileSystem(buildFileSystem(config, false)).readFrom(getLocalLogDirs())
                .writeTo(getHdfsLogDir(containerId, destFs, appWorkDir))
                .useCurrentLogFileName(Files.getNameWithoutExtension(
                        System.getProperty(GobblinYarnConfigurationKeys.GOBBLIN_YARN_CONTAINER_LOG_FILE_NAME)));

        builder.acceptsLogFileExtensions(config.hasPath(GobblinYarnConfigurationKeys.LOG_FILE_EXTENSIONS)
                ? ImmutableSet.copyOf(Splitter.on(",")
                        .splitToList(config.getString(GobblinYarnConfigurationKeys.LOG_FILE_EXTENSIONS)))
                : ImmutableSet.of());

        return builder.build();
    }

    /**
     * Return a new (non-cached) {@link FileSystem} instance. The {@link FileSystem} instance
     * returned by the method has automatic closing disabled. The user of the instance needs to handle closing of the
     * instance, typically as part of its shutdown sequence.
     */
    private FileSystem buildFileSystem(Config config, boolean isLocal) throws IOException {
        return isLocal ? FileSystem.newInstanceLocal(AUTO_CLOSE_CONFIG)
                : config.hasPath(ConfigurationKeys.FS_URI_KEY)
                        ? FileSystem.newInstance(URI.create(config.getString(ConfigurationKeys.FS_URI_KEY)),
                                AUTO_CLOSE_CONFIG)
                        : FileSystem.newInstance(AUTO_CLOSE_CONFIG);
    }

    /**
     * Multiple directories may be specified in the LOG_DIRS string. Split them up and return a list of {@link Path}s.
     * @return list of {@link Path}s to the log directories
     * @throws IOException
     */
    private List<Path> getLocalLogDirs() throws IOException {
        String logDirs = System.getenv(ApplicationConstants.Environment.LOG_DIRS.toString());
        return COMMA_SPLITTER.splitToList(logDirs).stream().map(e -> new Path(e)).collect(Collectors.toList());
    }

    private Path getHdfsLogDir(String containerId, FileSystem destFs, Path appWorkDir) throws IOException {
        Path logRootDir = PathUtils.combinePaths(appWorkDir.toString(),
                GobblinYarnConfigurationKeys.APP_LOGS_DIR_NAME, containerId);
        if (!destFs.exists(logRootDir)) {
            destFs.mkdirs(logRootDir);
        }
        return logRootDir;
    }
}