/**
* 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.core;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArrayList;
import com.cloudera.flume.reporter.ReportEvent;
import com.cloudera.flume.reporter.Reportable;
import com.cloudera.util.MultipleIOException;
/**
* This class composes many sinks into a single sink. This version is
* synchronous and the order event sinks are added controls the order they are
* written.
*
* TODO (jon) think about the semantics of partial failures in the multi sink.
*/
public class FanOutSink<S extends EventSink> extends EventSink.Base {
// TODO (jon) not sure if I need the synchronized list wrapper around this or
// not. Make a test to find out.
final List<S> sinks = Collections
.synchronizedList(new CopyOnWriteArrayList<S>());
public final static String R_SUBSINKS = "subsinks";
public FanOutSink() {
}
public FanOutSink(Collection<? extends S> l) {
sinks.addAll(l);
}
public FanOutSink(S... ss) {
sinks.addAll(Arrays.asList(ss));
}
public void add(S r) {
sinks.add(r);
}
public void addAll(Collection<? extends S> c) {
sinks.addAll(c);
}
public void drop(S r) {
sinks.remove(r);
}
protected Iterable<S> iter() {
return sinks;
}
/**
* Close all children
*/
@Override
public void close() throws IOException, InterruptedException {
List<IOException> exs = new ArrayList<IOException>();
for (S snk : sinks) {
try {
snk.close();
} catch (IOException ioe) {
exs.add(ioe);
}
}
if (!exs.isEmpty()) {
// From Hadoop 0.18.x api.
throw MultipleIOException.createIOException(exs);
}
}
/**
* Open all children.
*/
@Override
public void open() throws IOException, InterruptedException {
List<IOException> exs = new ArrayList<IOException>();
for (S snk : sinks) {
try {
snk.open();
} catch (IOException ioe) {
exs.add(ioe);
}
}
if (!exs.isEmpty()) {
// From Hadoop 0.18.x api.
throw MultipleIOException.createIOException(exs);
}
}
@Override
synchronized public void append(Event e) throws IOException,
InterruptedException {
List<IOException> exs = new ArrayList<IOException>();
for (S snk : sinks) {
try {
// Make a copy of the event for each branch of the fan out. This makes
// the events independently modifiable down each fanout path.
Event e2 = new EventImpl(e);
snk.append(e2);
super.append(e2);
} catch (IOException ioe) {
exs.add(ioe);
}
}
if (!exs.isEmpty()) {
// From Hadoop 0.18.x api.
throw MultipleIOException.createIOException(exs);
}
}
@Override
public String getName() {
return "Fanout";
}
@Override
public ReportEvent getMetrics() {
ReportEvent rpt = super.getMetrics();
rpt.setLongMetric(R_SUBSINKS, sinks.size());
return rpt;
}
@Override
public Map<String, Reportable> getSubMetrics() {
Map<String, Reportable> map = new HashMap<String, Reportable>();
int i = 0;
for (EventSink s : sinks) {
map.put(getName() + "[" + i + "]", s);
i++;
}
return map;
}
@Deprecated
@Override
public void getReports(String namePrefix, Map<String, ReportEvent> reports) {
super.getReports(namePrefix, reports);
int i = 0;
for (EventSink s : sinks) {
s.getReports(namePrefix + getName() + "." + i + ".", reports);
i++;
}
}
}