/*
* Copyright © 2014 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.data.stream;
import co.cask.cdap.api.flow.flowlet.StreamEvent;
import co.cask.cdap.common.conf.CConfiguration;
import co.cask.cdap.common.guice.ConfigModule;
import co.cask.cdap.common.guice.LocationRuntimeModule;
import co.cask.cdap.data.runtime.DataFabricModules;
import co.cask.cdap.data.runtime.DataSetsModules;
import co.cask.cdap.data2.transaction.stream.StreamAdmin;
import co.cask.cdap.data2.transaction.stream.StreamConfig;
import com.google.common.base.Charsets;
import com.google.common.base.Function;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import com.google.inject.Guice;
import com.google.inject.Injector;
import org.apache.hadoop.conf.Configuration;
import org.apache.twill.filesystem.Location;
import java.util.List;
import java.util.concurrent.TimeUnit;
/**
* Command line tool for tailing stream.
*/
public class StreamTailer {
public static void main(String[] args) throws Exception {
if (args.length < 1) {
System.out.println(String.format("Usage: java %s [streamName]", StreamTailer.class.getName()));
return;
}
String streamName = args[0];
CConfiguration cConf = CConfiguration.create();
Configuration hConf = new Configuration();
Injector injector = Guice.createInjector(new ConfigModule(cConf, hConf),
new DataFabricModules().getDistributedModules(),
new DataSetsModules().getDistributedModule(),
new LocationRuntimeModule().getDistributedModules());
StreamAdmin streamAdmin = injector.getInstance(StreamAdmin.class);
StreamConfig streamConfig = streamAdmin.getConfig(streamName);
Location streamLocation = streamConfig.getLocation();
List<Location> eventFiles = Lists.newArrayList();
for (Location partition : streamLocation.list()) {
if (!partition.isDirectory()) {
continue;
}
for (Location file : partition.list()) {
if (StreamFileType.EVENT.isMatched(file.getName())) {
eventFiles.add(file);
}
}
}
int generation = StreamUtils.getGeneration(streamConfig);
MultiLiveStreamFileReader reader = new MultiLiveStreamFileReader(streamConfig,
ImmutableList.copyOf(Iterables.transform(eventFiles, createOffsetConverter(generation))));
List<StreamEvent> events = Lists.newArrayList();
while (reader.read(events, 10, 100, TimeUnit.MILLISECONDS) >= 0) {
for (StreamEvent event : events) {
System.out.println(event.getTimestamp() + " " + Charsets.UTF_8.decode(event.getBody()));
}
events.clear();
}
reader.close();
}
private static Function<Location, StreamFileOffset> createOffsetConverter(final int generation) {
return new Function<Location, StreamFileOffset>() {
@Override
public StreamFileOffset apply(Location eventLocation) {
return new StreamFileOffset(eventLocation, 0L, generation);
}
};
}
}