/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 org.apache.whirr.cli.command;
import joptsimple.OptionParser;
import joptsimple.OptionSet;
import joptsimple.OptionSpec;
import org.apache.whirr.service.ClusterSpec;
import org.apache.whirr.service.Service;
import org.apache.whirr.service.ServiceFactory;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.io.Writer;
import java.util.List;
/**
* A command to destroy an instance from a cluster
*/
public class DestroyInstanceCommand extends AbstractClusterSpecCommand {
private OptionSpec<String> instanceOption = parser
.accepts("instance-id", "Cluster instance ID")
.withRequiredArg()
.ofType(String.class);
public DestroyInstanceCommand() throws IOException {
this(new ServiceFactory());
}
public DestroyInstanceCommand(ServiceFactory factory) {
super("destroy-instance", "Terminate and cleanup resources " +
"for a single instance.", factory);
}
@Override
public int run(InputStream in, PrintStream out,
PrintStream err, List<String> args) throws Exception {
OptionSet optionSet = parser.parse(args.toArray(new String[0]));
if (!optionSet.nonOptionArguments().isEmpty()) {
printUsage(parser, err);
return -1;
}
try {
if (!optionSet.hasArgument(instanceOption)) {
throw new IllegalArgumentException("You need to specify an instance ID.");
}
ClusterSpec clusterSpec = getClusterSpec(optionSet);
Service service = createService(clusterSpec.getServiceName());
String instanceId = optionSet.valueOf(instanceOption);
service.destroyInstance(clusterSpec, instanceId);
updateInstancesFile(clusterSpec, instanceId);
return 0;
} catch(IllegalArgumentException e) {
err.println(e.getMessage());
printUsage(parser, err);
return -1;
}
}
private void updateInstancesFile(ClusterSpec clusterSpec, String instanceId)
throws IOException {
File instances = new File(clusterSpec.getClusterDirectory(), "instances");
if (!instances.exists()) return; // no file to update
StringBuilder newLines = new StringBuilder();
/* Filter the line containing the instance ID */
BufferedReader reader = new BufferedReader(new FileReader(instances));
String line = null;
while((line = reader.readLine()) != null) {
if (!line.contains(instanceId)) {
newLines.append(line + "\n");
}
}
reader.close();
/* Rewrite the file to the disk */
Writer writer = new FileWriter(instances);
writer.write(newLines.toString());
writer.close();
}
private void printUsage(OptionParser parser, PrintStream stream) throws IOException {
stream.println("Usage: whirr destroy-instance --instance-id <ID> [OPTIONS]");
stream.println();
parser.printHelpOn(stream);
}
}