Java tutorial
/* * 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.usergrid.chop.client.ssh; import java.io.BufferedReader; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.net.InetSocketAddress; import java.net.Socket; import java.net.SocketAddress; import java.nio.file.Files; import java.nio.file.attribute.PosixFilePermissions; import java.util.Collection; import java.util.concurrent.Callable; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.apache.usergrid.chop.api.SshValues; import com.jcraft.jsch.Channel; import com.jcraft.jsch.ChannelExec; import com.jcraft.jsch.JSch; import com.jcraft.jsch.Session; import org.apache.commons.lang.NotImplementedException; public class Job implements Callable<ResponseInfo> { private static final Logger LOG = LoggerFactory.getLogger(Job.class); protected static final int SESSION_CONNECT_TIMEOUT = 100000; protected Collection<Command> commands; protected SshValues value; private Session session = null; protected Job() { } public Job(Collection<Command> commands, SshValues value) { this.commands = commands; this.value = value; } private void setSession() { JSch ssh; // wait until SSH port of remote end comes up boolean success = waitActive(SESSION_CONNECT_TIMEOUT); if (!success) { LOG.warn("Port 22 of {} did not open in time", value.getPublicIpAddress()); } // try to open ssh session try { Thread.sleep(30000); ssh = new JSch(); ssh.addIdentity(value.getSshKeyFile()); session = ssh.getSession(Utils.DEFAULT_USER, value.getPublicIpAddress()); session.setConfig("StrictHostKeyChecking", "no"); session.connect(); } catch (Exception e) { LOG.error("Error while connecting to ssh session of " + value.getPublicIpAddress(), e); session = null; } } @Override public ResponseInfo call() throws Exception { ResponseInfo response = new ResponseInfo(value.getPublicIpAddress()); setSession(); if (session == null) { String message = "Could not open ssh session for " + value.getPublicIpAddress(); response.addErrorMessage(message); return response; } for (Command command : commands) { if (command instanceof SCPCommand) { executeScp((SCPCommand) command, session, response); } else if (command instanceof SSHCommand) { executeSsh((SSHCommand) command, session, response); } } return response; } private void executeSsh(SSHCommand command, Session session, ResponseInfo response) { Channel channel = null; String message; try { channel = session.openChannel("exec"); ((ChannelExec) channel).setCommand(command.getCommand()); channel.connect(); BufferedReader inputReader = new BufferedReader(new InputStreamReader(channel.getInputStream())); BufferedReader errorReader = new BufferedReader( new InputStreamReader(((ChannelExec) channel).getErrStream())); while ((message = inputReader.readLine()) != null) { response.addMessage(message); LOG.info("SSH command response: {}", message); } while ((message = errorReader.readLine()) != null) { response.addMessage(message); LOG.info("Error in ssh command: {}", message); } inputReader.close(); errorReader.close(); } catch (Exception e) { message = "Error while sending ssh command to " + value.getPublicIpAddress(); LOG.warn(message, e); response.addErrorMessage(message); } finally { try { if (channel != null) { channel.disconnect(); } } catch (Exception e) { } } } private void executeScp(SCPCommand command, Session session, ResponseInfo response) { Channel channel = null; FileInputStream fis = null; OutputStream out = null; InputStream in = null; String message; try { // exec 'scp -t destFile' remotely String exec = "scp -t " + command.getDestinationFilePath(); channel = session.openChannel("exec"); ((ChannelExec) channel).setCommand(exec); // get I/O streams for remote scp out = channel.getOutputStream(); in = channel.getInputStream(); channel.connect(); if ((message = Utils.checkAck(in)) != null) { response.addErrorMessage(message); return; } File srcFile = new File(command.getSourceFilePath()); // send "C0<filemode> filesize filename", where filename should not include '/' StringBuilder sb = new StringBuilder(); String fileMode = PosixFilePermissions.toString(Files.getPosixFilePermissions(srcFile.toPath())); long filesize = srcFile.length(); exec = sb.append("C0").append(Utils.convertToNumericalForm(fileMode)).append(" ").append(filesize) .append(" ").append(srcFile.getName()).append("\n").toString(); out.write(exec.getBytes()); out.flush(); if ((message = Utils.checkAck(in)) != null) { response.addErrorMessage(message); return; } // send the content of source file fis = new FileInputStream(command.getSourceFilePath()); byte[] buf = new byte[1024]; while (true) { int len = fis.read(buf, 0, buf.length); if (len <= 0) { break; } out.write(buf, 0, len); } // send '\0' buf[0] = 0; out.write(buf, 0, 1); out.flush(); if ((message = Utils.checkAck(in)) != null) { response.addErrorMessage(message); } } catch (Exception e) { message = "Error while sending file to " + value.getPublicIpAddress(); LOG.warn(message, e); response.addErrorMessage(message); } finally { try { if (in != null) { in.close(); } } catch (Exception e) { } try { if (out != null) { out.close(); } } catch (Exception e) { } try { if (fis != null) { fis.close(); } } catch (Exception e) { } try { if (channel != null) { channel.disconnect(); } } catch (Exception e) { } } } protected boolean waitActive(int timeout) { LOG.info("Waiting maximum {} msecs for SSH port of {} to get active", timeout, value.getPublicIpAddress()); long startTime = System.currentTimeMillis(); while (System.currentTimeMillis() - startTime < timeout) { Socket s = null; try { s = new Socket(); s.setReuseAddress(true); SocketAddress sa = new InetSocketAddress(value.getPublicIpAddress(), 22); s.connect(sa, 2000); LOG.info("Port 22 of {} got opened", value.getPublicIpAddress()); return true; } catch (Exception e) { try { Thread.sleep(1000); } catch (InterruptedException ee) { } } finally { if (s != null) { try { s.close(); } catch (IOException e) { } } } } return false; } /** * Concatenates each block of SSH commands between SCP commands. * <p> * Contiguous SSH commands are converted to a single SSH command, separated by semicolons. * That way, more commands can be executed using a single <code>Channel</code> connection. * * @return the compressed collection of <code>Command</code>s. */ public static Collection<Command> compressCommands(Collection<Command> commands) { // TODO to be implemented throw new NotImplementedException(); } }