Java example source code file (HostProvisioner.java)

This example Java source code file (HostProvisioner.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

bufferedinputstream, channelexec, channelsftp, exception, file, fileinputstream, hostprovisioner, jsch, logger, override, session, skipping, string, uploading, util

The HostProvisioner.java Java example source code

/*
 *
 *  * Copyright 2015 Skymind,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 org.deeplearning4j.aws.ec2.provision;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Collection;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelExec;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.UserInfo;
/**
 * Meant for uploading files to remote servers
 * @author Adam Gibson
 *
 */
public class HostProvisioner implements UserInfo {

	private String host;
	private JSch jsch;
	private String user;
	private int port = 22;
	private String password;
	private static final Logger log = LoggerFactory.getLogger(HostProvisioner.class);

	/**
	 * 
	 * @param host host to connect to (public facing dns)
	 * @param user the user to connect with (default root otherwise)
	 * @param password the password to use if any
	 * @param port the port to connect to(default 22)
	 */
	public HostProvisioner(String host,String user,String password,int port) {
		super();
		this.host = host;
		this.user = user;
		this.port = port;
		this.password = password;
		jsch = new JSch();

	}

	/**
	 * Connects to port 22
	 * @param host host to connect to (public facing dns)
	 * @param user the user to connect with (default root otherwise)
	 * @param password the password to use if any
	 */
	public HostProvisioner(String host,String user,String password) {
		this(host,user,password,22);
	}
	/**
	 * Connects to port 22
	 * @param host host to connect to (public facing dns)
	 * @param user the user to connect with (default root otherwise)
	 */
	public HostProvisioner(String host,String user) {
		this(host,user,"",22);
	}

	/**
	 * Connects to port 22, user root, with no password
	 * @param host host to connect to (public facing dns)
	 */
	public HostProvisioner(String host) {
		this(host,"root","",22);
	}





	public void uploadAndRun(String script,String rootDir) throws Exception {
		String remoteName = rootDir.isEmpty() ? new File(script).getName() : rootDir + "/" + new File(script).getName();
		upload(new File(script),remoteName);

		String remoteCommand = remoteName.charAt(0) != '/' ? "./" + remoteName : remoteName;
		remoteCommand = "chmod +x " + remoteCommand + " && " + remoteCommand;
		runRemoteCommand(remoteCommand);
	}

	public void runRemoteCommand(String remoteCommand) throws Exception {
		Session session = getSession();
		session.connect();
		ChannelExec channel = (ChannelExec) session.openChannel("exec");


		channel.setCommand(remoteCommand);
		channel.setErrStream(System.err);
		channel.setPty(true);

		channel.setOutputStream(System.out);
		channel.connect();
		channel.start();
		InputStream input = channel.getInputStream();

		//start reading the input from the executed commands on the shell
		byte[] tmp = new byte[60000];
		while (true) {
			while (input.available() > 0) {
				int i = input.read(tmp, 0, tmp.length);
				if (i < 0)
					break;
				log.info(new String(tmp, 0, i));
			}
			if (channel.isClosed()){
				log.info("exit-status: " + channel.getExitStatus());
				break;
			}

		}

		channel.disconnect();
		session.disconnect();


	}


	private Session getSession() throws Exception {
		Session session = jsch.getSession(user, host, port);
		session.setUserInfo(this);
		return session;
	}

	/**
	 * Creates the directory for the file if necessary 
	 * and uploads the file
	 * @param from the directory to upload from
	 * @param to the destination directory on the remote server
	 * @throws Exception
	 */
	public void uploadForDeployment(String from,String to) throws Exception {
		File fromFile = new File(from);
		if(!to.isEmpty() && fromFile.isDirectory())
			mkDir(to);
		else
			upload(from,to);


	}

	public void addKeyFile(String keyFile) throws Exception {
		jsch.addIdentity(keyFile);
	}

	//creates the directory to upload to
	private void mkDir(String dir) throws Exception {
		Session session = getSession();
		session.connect();
		Channel channel = session.openChannel("sftp");
		channel.connect();

		ChannelSftp c = (ChannelSftp) channel;
		if(!fileExists(dir,c))
			c.mkdir(dir);
		c.exit();
		session.disconnect();
	}

	private boolean fileExists(String dir,ChannelSftp channel) {
		try {
			channel.stat(dir);
			return true;
		}catch(Exception e) {
			return false;
		}
	}


	//uploads the file or listed files in a directory
	private void upload(String fileOrDir,String uploadRootDir) throws Exception {
		if(uploadRootDir.isEmpty())
			uploadRootDir = ".";
		File origin = new File(fileOrDir);

		if(fileOrDir.endsWith(".tar") || fileOrDir.endsWith(".tar.gz")) {
			upload(new File(fileOrDir),uploadRootDir);
			untar(uploadRootDir);
		}
		else if(origin.isFile()) {
			upload(new File(fileOrDir),uploadRootDir);
		}
		else {
			File[] childFiles = origin.listFiles();
			if(childFiles != null)
				upload(Arrays.asList(childFiles),uploadRootDir);

		}
	}

	private void untar(String targetRemoteFile) throws Exception {
		this.runRemoteCommand("tar xvf " + targetRemoteFile);
	}

	private void upload(Collection<File> files,String rootDir) throws Exception {
		Session session = getSession();
		session.connect();
		Channel channel = session.openChannel("sftp");
		channel.connect();

		ChannelSftp c = (ChannelSftp) channel;
		for(File f : files) {
			if(f.isDirectory()) {
				log.warn("Skipping " + f.getName());
				continue;
			}

			log.info("Uploading " + f.getName());
			BufferedInputStream bis = new BufferedInputStream(new FileInputStream(f));
			c.put(bis, rootDir + "/" + f.getName());
			bis.close();

		}

		channel.disconnect();
		session.disconnect();


	}

	private void upload(File f,String remoteFile) throws Exception {
		Session session = getSession();
		int numRetries = 0;
		while(numRetries < 3 && !session.isConnected()) {
			try {
				session.connect();
			}catch(Exception e) {
				numRetries++;
			}
		}

        try {
            Channel channel = session.openChannel("sftp");


            channel.connect();

            ChannelSftp c = (ChannelSftp) channel;

            BufferedInputStream bis = new BufferedInputStream(new FileInputStream(f));
            if (this.fileExists(remoteFile, c))
                if (f.isDirectory())
                    c.rmdir(remoteFile);
                else
                    c.rm(remoteFile);
            c.put(bis, remoteFile);
            bis.close();
            c.exit();
            session.disconnect();
        }catch(Exception e) {
            log.info("Session was down...trying again",e);
            upload(f,remoteFile);
        }
	}



	@Override
	public String getPassphrase() {
		return this.password;
	}


	@Override
	public String getPassword() {
		return this.password;
	}


	@Override
	public boolean promptPassphrase(String arg0) {
		return true;
	}


	@Override
	public boolean promptPassword(String arg0) {
		return true;

	}


	@Override
	public boolean promptYesNo(String arg0) {
		return true;

	}


	@Override
	public void showMessage(String arg0) {
		log.info(arg0);
	}

}