001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017 package org.apache.camel.component.exec.impl;
018
019 import java.io.ByteArrayInputStream;
020 import java.io.ByteArrayOutputStream;
021 import java.io.File;
022 import java.io.IOException;
023 import java.io.InputStream;
024 import java.util.List;
025
026 import org.apache.camel.component.exec.ExecCommand;
027 import org.apache.camel.component.exec.ExecCommandExecutor;
028 import org.apache.camel.component.exec.ExecEndpoint;
029 import org.apache.camel.component.exec.ExecException;
030 import org.apache.camel.component.exec.ExecResult;
031 import org.apache.commons.exec.CommandLine;
032 import org.apache.commons.exec.DefaultExecutor;
033 import org.apache.commons.exec.ExecuteException;
034 import org.apache.commons.exec.ExecuteWatchdog;
035 import org.apache.commons.exec.PumpStreamHandler;
036 import org.apache.commons.exec.ShutdownHookProcessDestroyer;
037 import org.apache.commons.io.IOUtils;
038 import org.apache.commons.logging.Log;
039 import org.apache.commons.logging.LogFactory;
040
041 import static org.apache.camel.util.ObjectHelper.notNull;
042
043 /**
044 * Executes the command utilizing the <a
045 * href="http://commons.apache.org/exec/">Apache Commons exec library</a>. Adds
046 * a shutdown hook for every executed process.
047 */
048 public class DefaultExecCommandExecutor implements ExecCommandExecutor {
049
050 private static final Log LOG = LogFactory.getLog(DefaultExecCommandExecutor.class);
051
052 public ExecResult execute(ExecCommand command) {
053 notNull(command, "command");
054
055 ByteArrayOutputStream out = new ByteArrayOutputStream();
056 ByteArrayOutputStream err = new ByteArrayOutputStream();
057
058 DefaultExecutor executor = prepareDefaultExecutor(command);
059 // handle error and output of the process and write them to the given
060 // out stream
061 PumpStreamHandler handler = new PumpStreamHandler(out, err, command.getInput());
062 executor.setStreamHandler(handler);
063
064 CommandLine cl = toCommandLine(command);
065
066 try {
067 int exitValue = executor.execute(cl);
068 // if the size is zero, we have no output, so construct the result
069 // with null (required by ExecResult)
070 InputStream stdout = out.size() == 0 ? null : new ByteArrayInputStream(out.toByteArray());
071 InputStream stderr = err.size() == 0 ? null : new ByteArrayInputStream(err.toByteArray());
072 ExecResult result = new ExecResult(command, stdout, stderr, exitValue);
073 return result;
074
075 } catch (ExecuteException ee) {
076 LOG.error("ExecException while executing command: " + command.toString() + " - " + ee.getMessage());
077 throw new ExecException("Failed to execute command " + command, ee);
078 } catch (IOException ioe) {
079 // invalid working dir
080 LOG.error("IOException while executing command: " + command.toString() + " - " + ioe.getMessage());
081 throw new ExecException("Unable to execute command " + command, ioe);
082 } finally {
083 // the inputStream must be closed after the execution
084 IOUtils.closeQuietly(command.getInput());
085 }
086 }
087
088 protected DefaultExecutor prepareDefaultExecutor(ExecCommand execCommand) {
089 DefaultExecutor executor = new DefaultExecutor();
090 executor.setExitValues(null);
091
092 if (execCommand.getWorkingDir() != null) {
093 executor.setWorkingDirectory(new File(execCommand.getWorkingDir()).getAbsoluteFile());
094 }
095 if (execCommand.getTimeout() != ExecEndpoint.NO_TIMEOUT) {
096 executor.setWatchdog(new ExecuteWatchdog(execCommand.getTimeout()));
097 }
098 executor.setProcessDestroyer(new ShutdownHookProcessDestroyer());
099 return executor;
100 }
101
102 /**
103 * Transforms an {@link ExecCommand} to a {@link CommandLine}. No quoting fo
104 * the arguments is used.
105 *
106 * @param execCommand a not-null <code>ExecCommand</code> instance.
107 * @return a {@link CommandLine} object.
108 */
109 protected CommandLine toCommandLine(ExecCommand execCommand) {
110 notNull(execCommand, "execCommand");
111 CommandLine cl = new CommandLine(execCommand.getExecutable());
112 List<String> args = execCommand.getArgs();
113 for (String arg : args) {
114 // do not handle quoting here, it is already quoted
115 cl.addArgument(arg, false);
116 }
117 return cl;
118 }
119 }