/**
* 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 org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.cloudera.flume.conf.Context;
import com.cloudera.flume.conf.SourceFactory.SourceBuilder;
import com.cloudera.flume.core.Event;
import com.cloudera.flume.core.EventImpl;
import com.cloudera.flume.core.EventSource;
import com.cloudera.util.CharEncUtils;
import com.cloudera.util.Clock;
/**
* A synthetic source that just creates a specified number of random events with
* a specified number of attributes with specified attribute size, and specified
* value size.
*
* 'open' resets the source's seed and will generate essentially the same stream
* of events.
*/
public class AttrSynthSource extends EventSource.Base {
static final Logger LOG = LoggerFactory.getLogger(AttrSynthSource.class);
final long msgs;
final int attrs;
final int valSz;
final int attrSz;
final String[] attrNames;
final Random rand;
final long seed;
long count = 0;
public AttrSynthSource(long msgs, int attrs, int attrsz, int valsz, long seed) {
this.msgs = msgs;
this.seed = seed;
this.rand = new Random(seed);
this.attrs = attrs;
this.attrSz = attrsz;
this.valSz = valsz;
// generate random but consistent for every event attributes.
this.attrNames = new String[attrs];
for (int i = 0; i < attrs; i++) {
attrNames[i] = getRandASCIIString(attrSz);
}
}
/**
* This is not meant to be efficient.
*/
String getRandASCIIString(int len) {
byte[] bytes = new byte[len];
rand.nextBytes(bytes);
String s = new String(bytes, CharEncUtils.RAW);
return s.substring(0, len);
}
@Override
public void close() throws IOException {
LOG.info("closing AttrSynthSource(" + msgs + ", " + attrs + ", " + attrSz
+ ", " + valSz + " )");
}
@Override
public Event next() throws IOException {
if (count >= msgs)
return null;// end marker if gotten to count
count++;
Event e = new EventImpl(new byte[0]);
for (String a : attrNames) {
byte[] val = new byte[valSz];
rand.nextBytes(val);
e.set(a, val);
}
updateEventProcessingStats(e);
return e;
}
@Override
public void open() throws IOException {
LOG.info("opening AttrSynthSource(" + msgs + ", " + attrs + ", " + attrSz
+ ", " + valSz + " )");
// reset random num gen and count.
count = 0;
rand.setSeed(seed);
}
public static SourceBuilder builder() {
return new SourceBuilder() {
@Override
public EventSource build(Context ctx, String... argv) {
if (argv.length < 4 || argv.length > 5) {
throw new IllegalArgumentException(
"usage: attrsynth(count, attrs, attrSz, valSz[,rseed=curtime]) // count=0 infinite");
}
long count = Integer.parseInt(argv[0]);
int attrs = Integer.parseInt(argv[1]);
int attrSz = Integer.parseInt(argv[2]);
int valSz = Integer.parseInt(argv[3]);
long seed = Clock.unixTime();
if (argv.length >= 4) {
seed = Integer.parseInt(argv[4]);
}
return new AttrSynthSource(count, attrs, attrSz, valSz, seed);
}
};
}
}