SshProcess.java

/**
 * Copyright (c) 2008-2016, XebiaLabs B.V., All rights reserved.
 *
 *
 * Overthere is licensed under the terms of the GPLv2
 * <http://www.gnu.org/licenses/old-licenses/gpl-2.0.html>, like most XebiaLabs Libraries.
 * There are special exceptions to the terms and conditions of the GPLv2 as it is applied to
 * this software, see the FLOSS License Exception
 * <http://github.com/xebialabs/overthere/blob/master/LICENSE>.
 *
 * This program is free software; you can redistribute it and/or modify it under the terms
 * of the GNU General Public License as published by the Free Software Foundation; version 2
 * of the License.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this
 * program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth
 * Floor, Boston, MA 02110-1301  USA
 */
package com.xebialabs.overthere.ssh;

import java.io.InputStream;
import java.io.OutputStream;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.xebialabs.overthere.CmdLine;
import com.xebialabs.overthere.OperatingSystemFamily;
import com.xebialabs.overthere.OverthereProcess;
import com.xebialabs.overthere.RuntimeIOException;

import net.schmizz.sshj.common.SSHException;
import net.schmizz.sshj.connection.ConnectionException;
import net.schmizz.sshj.connection.channel.direct.Session;
import net.schmizz.sshj.connection.channel.direct.Signal;
import net.schmizz.sshj.transport.TransportException;

import static com.xebialabs.overthere.util.OverthereUtils.checkArgument;
import static java.lang.String.format;

class SshProcess implements OverthereProcess {
    private SshConnection connection;
    private final Session session;
    private final String obfuscatedCommandLine;
    private final Session.Command command;
    private int exitValue = -1;

    SshProcess(final SshConnection connection, final OperatingSystemFamily os, final Session session, final CmdLine commandLine) throws TransportException,
            ConnectionException {
        this.connection = connection;
        this.session = session;
        this.obfuscatedCommandLine = commandLine.toCommandLine(os, true);
        this.command = session.exec(commandLine.toCommandLine(os, false));
    }

    @Override
    public synchronized OutputStream getStdin() {
        checkArgument(command != null, "Process for command line [{}] is not running", obfuscatedCommandLine);

        return command.getOutputStream();
    }

    @Override
    public synchronized InputStream getStdout() {
        checkArgument(command != null, "Process for command line [{}] is not running", obfuscatedCommandLine);

        return command.getInputStream();
    }

    @Override
    public synchronized InputStream getStderr() {
        checkArgument(command != null, "Process for command line [{}] is not running", obfuscatedCommandLine);

        return command.getErrorStream();
    }

    @Override
    public synchronized int waitFor() {
        if (command == null) {
            return exitValue;
        }

        try {
            command.join();
            Integer exitStatus = command.getExitStatus();
            logger.info("Command [{}] on {} returned exit code {}", new Object[]{obfuscatedCommandLine, connection, exitStatus});
            closeSession();
            if (exitStatus == null) {
                logger.warn("Command [{}] on {} could not be started. Returning exit code -1", obfuscatedCommandLine, connection);
                exitValue = -1;
            } else {
                exitValue = exitStatus;
            }
            return exitValue;
        } catch (ConnectionException e) {
            throw new RuntimeIOException(format("Caught exception while awaiting end of process for command [%s] on [%s]", obfuscatedCommandLine, connection), e);
        }
    }

    @Override
    public synchronized void destroy() {
        if (command == null) {
            return;
        }

//        try {
//            command.signal(Signal.KILL);
//        } catch (TransportException e) {
//            logger.warn("Could not send the KILL signal to the command, closing the session.", e);
//        } finally {
            closeSession();
//        }
    }

    @Override
    public synchronized int exitValue() {
        if (command != null) {
            throw new IllegalThreadStateException(format("Process for command [%s] on [%s] is still running", obfuscatedCommandLine, connection));
        }

        return exitValue;
    }

    private void closeSession() {
        if (session.isOpen()) {
            try {
                session.close();
            } catch (SSHException e) {
                throw new RuntimeIOException("Could not close the SSH session", e);
            }
        }
    }

    private static Logger logger = LoggerFactory.getLogger(SshProcess.class);

}