io.soabase.core.features.logging.LoggingReader.java Source code

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Here is the source code for io.soabase.core.features.logging.LoggingReader.java

Source

/**
 * Copyright 2014 Jordan Zimmerman
 *
 * Licensed 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 io.soabase.core.features.logging;

import com.google.common.base.Preconditions;
import com.google.common.base.Predicate;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import com.google.common.io.ByteStreams;
import com.google.common.io.Files;
import jersey.repackaged.com.google.common.collect.Sets;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.StreamingOutput;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Collection;
import java.util.List;
import java.util.Set;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import java.util.zip.ZipInputStream;

public class LoggingReader {
    private final Collection<File> mainFiles;
    private final Collection<File> archiveDirectories;

    public LoggingReader(Collection<File> mainFiles, Collection<File> archiveDirectories) {
        mainFiles = Preconditions.checkNotNull(mainFiles, "mainFiles cannot be null");
        archiveDirectories = Preconditions.checkNotNull(archiveDirectories, "archiveDirectories cannot be null");

        this.mainFiles = ImmutableSet.copyOf(mainFiles);
        this.archiveDirectories = ImmutableSet.copyOf(archiveDirectories);
    }

    public List<LoggingFile> listLoggingFiles() {
        Set<File> usedSet = Sets.newHashSet();
        List<LoggingFile> files = Lists.newArrayList();

        for (File f : mainFiles) {
            if (f.exists()) {
                if (usedSet.add(f)) {
                    files.add(new LoggingFile(f));
                }
            }
        }

        for (File dir : archiveDirectories) {
            for (File f : Files.fileTreeTraverser().children(dir)) {
                if (usedSet.add(f)) {
                    files.add(new LoggingFile(f));
                }
            }
        }

        return files;
    }

    public File keyToFile(final String key) {
        LoggingFile foundFile = Iterables.find(listLoggingFiles(), new Predicate<LoggingFile>() {
            @Override
            public boolean apply(LoggingFile loggingFile) {
                return loggingFile.getKey().equals(key);
            }
        }, null);
        return (foundFile != null) ? foundFile.getFile() : null;
    }

    public Object keyToEntity(String key, final boolean gzipOutput) {
        final File file = keyToFile(key);
        if (file == null) {
            return null;
        }

        if (gzipOutput && file.getName().endsWith(".gz")) {
            return file;
        }

        return new StreamingOutput() {
            @Override
            public void write(OutputStream entityOut) throws IOException, WebApplicationException {
                InputStream in = null;
                try {
                    if (file.getName().endsWith(".zip")) {
                        ZipInputStream zipInputStream = new ZipInputStream(new FileInputStream(file));
                        zipInputStream.getNextEntry();
                        in = new BufferedInputStream(zipInputStream);
                    } else if (file.getName().endsWith(".gz") || file.getName().endsWith(".gzip")) {
                        in = new BufferedInputStream(new GZIPInputStream(new FileInputStream(file)));
                    } else {
                        in = new BufferedInputStream(new FileInputStream(file));
                    }
                    if (gzipOutput) {
                        GZIPOutputStream out = new GZIPOutputStream(entityOut);
                        ByteStreams.copy(in, out);
                        out.finish();
                    } else {
                        ByteStreams.copy(in, entityOut);
                    }
                } finally {
                    if (in != null) {
                        in.close();
                    }
                }
            }
        };
    }
}