/**
* 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.camel.component.exec.impl;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import org.apache.camel.component.exec.ExecCommand;
import org.apache.camel.component.exec.ExecCommandExecutor;
import org.apache.camel.component.exec.ExecEndpoint;
import org.apache.camel.component.exec.ExecException;
import org.apache.camel.component.exec.ExecResult;
import org.apache.commons.exec.CommandLine;
import org.apache.commons.exec.DefaultExecutor;
import org.apache.commons.exec.ExecuteException;
import org.apache.commons.exec.ExecuteWatchdog;
import org.apache.commons.exec.PumpStreamHandler;
import org.apache.commons.exec.ShutdownHookProcessDestroyer;
import org.apache.commons.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import static org.apache.camel.util.ObjectHelper.notNull;
/**
* Executes the command utilizing the <a
* href="http://commons.apache.org/exec/">Apache Commons exec library</a>. Adds
* a shutdown hook for every executed process.
*/
public class DefaultExecCommandExecutor implements ExecCommandExecutor {
private static final Logger LOG = LoggerFactory.getLogger(DefaultExecCommandExecutor.class);
public ExecResult execute(ExecCommand command) {
notNull(command, "command");
ByteArrayOutputStream out = new ByteArrayOutputStream();
ByteArrayOutputStream err = new ByteArrayOutputStream();
DefaultExecutor executor = prepareDefaultExecutor(command);
// handle error and output of the process and write them to the given
// out stream
PumpStreamHandler handler = new PumpStreamHandler(out, err, command.getInput());
executor.setStreamHandler(handler);
CommandLine cl = toCommandLine(command);
try {
int exitValue = executor.execute(cl);
// if the size is zero, we have no output, so construct the result
// with null (required by ExecResult)
InputStream stdout = out.size() == 0 ? null : new ByteArrayInputStream(out.toByteArray());
InputStream stderr = err.size() == 0 ? null : new ByteArrayInputStream(err.toByteArray());
ExecResult result = new ExecResult(command, stdout, stderr, exitValue);
return result;
} catch (ExecuteException ee) {
LOG.error("ExecException while executing command: " + command.toString() + " - " + ee.getMessage());
throw new ExecException("Failed to execute command " + command, ee);
} catch (IOException ioe) {
// invalid working dir
LOG.error("IOException while executing command: " + command.toString() + " - " + ioe.getMessage());
throw new ExecException("Unable to execute command " + command, ioe);
} finally {
// the inputStream must be closed after the execution
IOUtils.closeQuietly(command.getInput());
}
}
protected DefaultExecutor prepareDefaultExecutor(ExecCommand execCommand) {
DefaultExecutor executor = new DefaultExecutor();
executor.setExitValues(null);
if (execCommand.getWorkingDir() != null) {
executor.setWorkingDirectory(new File(execCommand.getWorkingDir()).getAbsoluteFile());
}
if (execCommand.getTimeout() != ExecEndpoint.NO_TIMEOUT) {
executor.setWatchdog(new ExecuteWatchdog(execCommand.getTimeout()));
}
executor.setProcessDestroyer(new ShutdownHookProcessDestroyer());
return executor;
}
/**
* Transforms an {@link ExecCommand} to a {@link CommandLine}. No quoting fo
* the arguments is used.
*
* @param execCommand a not-null <code>ExecCommand</code> instance.
* @return a {@link CommandLine} object.
*/
protected CommandLine toCommandLine(ExecCommand execCommand) {
notNull(execCommand, "execCommand");
CommandLine cl = new CommandLine(execCommand.getExecutable());
List<String> args = execCommand.getArgs();
for (String arg : args) {
// do not handle quoting here, it is already quoted
cl.addArgument(arg, false);
}
return cl;
}
}