/**
* 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.debug;
import java.io.IOException;
import java.util.Random;
import com.cloudera.flume.conf.Context;
import com.cloudera.flume.conf.SinkFactory.SinkDecoBuilder;
import com.cloudera.flume.core.Event;
import com.cloudera.flume.core.EventSink;
import com.cloudera.flume.core.EventSinkDecorator;
import com.google.common.base.Preconditions;
/**
* This sink essentially acts as a pass through decorator, but will throw an
* IOException with some probability. This is useful for testing a FailOverSink,
* or for fault tolerance testing.
*/
public class FlakeyEventSink<S extends EventSink> extends EventSinkDecorator<S> {
double prob; // probability of throwing an exception
Random rand;
public FlakeyEventSink(S s, double prob, long seed) {
super(s);
Preconditions.checkArgument(prob <= 1.0);
Preconditions.checkArgument(prob >= 0.0);
this.prob = prob;
this.rand = new Random(seed);
}
@Override
public void append(Event e) throws IOException , InterruptedException {
if (rand.nextDouble() < prob) {
throw new IOException("flakiness struck and caused a failure");
}
super.append(e);
}
public static SinkDecoBuilder builder() {
return new SinkDecoBuilder() {
@Override
public EventSinkDecorator<EventSink> build(Context context,
String... argv) {
if (argv.length == 0) {
throw new IllegalArgumentException(
"usage: flakey(failprobability,[seed])");
}
double d = Double.parseDouble(argv[0]);
long seed = 0;
if (argv.length > 1) {
seed = Integer.parseInt(argv[1]);
} else {
seed = System.currentTimeMillis();
}
return new FlakeyEventSink<EventSink>(null, d, seed);
}
};
}
}