co.cask.cdap.logging.framework.LogFileOutputStream.java Source code

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Here is the source code for co.cask.cdap.logging.framework.LogFileOutputStream.java

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/*
 * Copyright  2017 Cask Data, Inc.
 *
 * 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 co.cask.cdap.logging.framework;

import ch.qos.logback.classic.spi.ILoggingEvent;
import co.cask.cdap.common.io.Syncable;
import co.cask.cdap.logging.serialize.LoggingEvent;
import com.google.common.io.Closeables;
import org.apache.avro.Schema;
import org.apache.avro.file.DataFileWriter;
import org.apache.avro.generic.GenericDatumWriter;
import org.apache.avro.generic.GenericRecord;
import org.apache.twill.filesystem.Location;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.Closeable;
import java.io.Flushable;
import java.io.IOException;
import java.io.OutputStream;

/**
 * Represents output stream for a log file.
 *
 * Since there is no way to check the state of the underlying file on an exception,
 * all methods of this class assume that the file state is bad on any exception and close the file.
 */

class LogFileOutputStream implements Closeable, Flushable, Syncable {
    private static final Logger LOG = LoggerFactory.getLogger(LogFileOutputStream.class);

    private final Location location;
    private final long createTime;
    private final Schema schema;
    private final Closeable closeable;

    private OutputStream outputStream;
    private DataFileWriter<GenericRecord> dataFileWriter;
    private long fileSize;

    LogFileOutputStream(Location location, Schema schema, int syncIntervalBytes, long createTime,
            Closeable closeable) throws IOException {
        this.location = location;
        this.schema = schema;
        this.closeable = closeable;
        try {
            this.outputStream = location.getOutputStream();
            this.dataFileWriter = new DataFileWriter<>(new GenericDatumWriter<GenericRecord>(schema));
            this.dataFileWriter.create(schema, outputStream);
            this.dataFileWriter.setSyncInterval(syncIntervalBytes);
            this.createTime = createTime;
            this.fileSize = 0;
        } catch (IOException e) {
            Closeables.closeQuietly(outputStream);
            Closeables.closeQuietly(dataFileWriter);
            throw e;
        }
    }

    Location getLocation() {
        return location;
    }

    void append(ILoggingEvent event) throws IOException {
        dataFileWriter.append(LoggingEvent.encode(schema, event));
    }

    /**
     * get create time of the file
     * @return create time
     */
    long getCreateTime() {
        return createTime;
    }

    /**
     * get the number of bytes written to output stream
     * @return file size
     */
    long getSize() {
        return fileSize;
    }

    @Override
    public void flush() throws IOException {
        dataFileWriter.flush();
    }

    @Override
    public void sync() throws IOException {
        fileSize = dataFileWriter.sync();
        if (outputStream instanceof org.apache.hadoop.fs.Syncable) {
            ((org.apache.hadoop.fs.Syncable) outputStream).hsync();
        } else {
            outputStream.flush();
        }
    }

    @Override
    public void close() throws IOException {
        LOG.trace("Closing file {}", location);
        try {
            dataFileWriter.close();
        } finally {
            closeable.close();
        }
    }
}