/**
* Licensed to Cloudera, Inc. under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Cloudera, Inc. 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 com.cloudera.flume.handlers.hdfs;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.FlushingSequenceFileWriter;
import org.apache.hadoop.io.RawSequenceFileWriter;
import org.apache.hadoop.io.SequenceFile;
import org.apache.hadoop.io.SequenceFile.CompressionType;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.cloudera.flume.conf.Context;
import com.cloudera.flume.conf.FlumeConfiguration;
import com.cloudera.flume.conf.SinkFactory.SinkBuilder;
import com.cloudera.flume.core.Event;
import com.cloudera.flume.core.EventSink;
import com.cloudera.util.FileUtil;
import com.google.common.base.Preconditions;
/**
* This is an event sink that dumps to a hadoop sequence file on the local file
* system..
*/
public class SeqfileEventSink extends EventSink.Base {
static final Logger LOG = LoggerFactory.getLogger(SeqfileEventSink.class);
private SequenceFile.Writer writer;
private long count = 0;
private boolean bufferedIO = false;
private String tag;
private File f;
public SeqfileEventSink(File f) throws IOException {
this.f = f;
this.tag = f.getName();
LOG.info("constructed new seqfile event sink: file=" + f);
}
/*
* This is assumed to be open
*/
public void open() throws IOException {
LOG.debug("opening " + f);
// need absolute file to get full path. (pwd files have not parent file)
// make directories if necessary
if (!FileUtil.makeDirs(f.getAbsoluteFile().getParentFile())) {
throw new IOException("Unable to create directory"
+ f.getAbsoluteFile().getParentFile() + " for writing");
}
FlumeConfiguration conf = FlumeConfiguration.get();
FileSystem fs = FileSystem.getLocal(conf);
try {
if (conf.getWALOutputBuffering()) {
writer = RawSequenceFileWriter.createWriter(fs, conf,
new Path(f.getAbsolutePath()), WriteableEventKey.class,
WriteableEvent.class, CompressionType.NONE);
} else {
writer = FlushingSequenceFileWriter.createWriter(conf, f,
WriteableEventKey.class, WriteableEvent.class);
}
} catch (FileNotFoundException fnfe) {
LOG.error("Possible permissions problem when creating " + f, fnfe);
throw fnfe;
}
}
/**
* @throws IOException
*
*/
public void close() throws IOException {
LOG.debug("closing " + f);
if (writer == null) {
// allow closing twice.
return;
}
writer.close();
writer = null;
LOG.info("closed " + f);
}
public void append(Event e) throws IOException, InterruptedException {
Preconditions.checkNotNull(writer,
"Attempt to append to a sink that is closed!");
WriteableEvent we = new WriteableEvent(e);
writer.append(we.getEventKey(), we);
// flush if we are not buffering
if (!bufferedIO)
writer.sync(); // this isn't flushing or sync'ing on local file system :(
count++;
super.append(e);
}
public void setBufferIO(boolean bufferedIO) {
this.bufferedIO = bufferedIO;
}
public String getTag() {
return tag;
}
public static SinkBuilder builder() {
return new SinkBuilder() {
@Override
public EventSink build(Context context, String... args) {
Preconditions.checkArgument(args.length == 1,
"usage: seqfile(filename)");
try {
return new SeqfileEventSink(new File(args[0]));
} catch (IOException e) {
throw new IllegalArgumentException("Unable to open file for writing "
+ args[0]);
}
}
};
}
}