src/java/org/apache/ivy/plugins/repository/ssh/SshRepository.java - ant-ivy - Git at Google

 /*
  *  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
  *
  *      https://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.ivy.plugins.repository.ssh;

 import java.io.BufferedReader;
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.StringReader;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.util.ArrayList;
 import java.util.List;

 import org.apache.ivy.core.settings.TimeoutConstraint;
 import org.apache.ivy.plugins.repository.Resource;
 import org.apache.ivy.util.Message;

 import com.jcraft.jsch.ChannelExec;
 import com.jcraft.jsch.JSchException;
 import com.jcraft.jsch.Session;

 /**
  * Ivy Repository based on SSH
  */
 public class SshRepository extends AbstractSshBasedRepository {

     private static final int BUFFER_SIZE = 64 * 1024;

     private static final String ARGUMENT_PLACEHOLDER = "%arg";

     private static final int POLL_SLEEP_TIME = 500;

     private char fileSeparator = '/';

     private String listCommand = "ls -1";

     private String existCommand = "ls";

     private String createDirCommand = "mkdir";

     private String publishPermissions = null;

     public SshRepository() {

     }

     public SshRepository(final TimeoutConstraint timeoutConstraint) {
         super(timeoutConstraint);
     }

     /**
      * create a new resource with lazy initializing
      *
      * @param source String
      * @return Resource
      */
     public Resource getResource(String source) {
         Message.debug("SShRepository:getResource called: " + source);
         return new SshResource(this, source);
     }

     /**
      * Fetch the needed file information for a given file (size, last modification time) and report
      * it back in a SshResource
      *
      * @param source
      *            ssh uri for the file to get info for
      * @return SshResource filled with the needed information
      * @see org.apache.ivy.plugins.repository.Repository#getResource(java.lang.String)
      */
     public SshResource resolveResource(String source) {
         Message.debug("SShRepository:resolveResource called: " + source);
         SshResource result = null;
         Session session = null;
         try {
             session = getSession(source);
             Scp myCopy = new Scp(session);
             Scp.FileInfo fileInfo = myCopy.getFileinfo(new URI(source).getPath());
             result = new SshResource(this, source, true, fileInfo.getLength(),
                     fileInfo.getLastModified());
         } catch (IOException | URISyntaxException e) {
             if (session != null) {
                 releaseSession(session, source);
             }
             result = new SshResource();
         } catch (RemoteScpException e) {
             result = new SshResource();
         }
         Message.debug("SShRepository:resolveResource end.");
         return result;
     }

     /**
      * Reads out the output of a ssh session exec
      *
      * @param channel
      *            Channel to read from
      * @param strStdout
      *            StringBuilder that receives Session Stdout output
      * @param strStderr
      *            StringBuilder that receives Session Stderr output
      * @throws IOException
      *             in case of trouble with the network
      */
     private void readSessionOutput(ChannelExec channel, StringBuilder strStdout,
             StringBuilder strStderr) throws IOException {
         InputStream stdout = channel.getInputStream();
         InputStream stderr = channel.getErrStream();

         try {
             channel.connect();
         } catch (JSchException jsche) {
             throw new IOException("Channel connection problems", jsche);
         }

         byte[] buffer = new byte[BUFFER_SIZE];
         while (true) {
             int avail = 0;
             while ((avail = stdout.available()) > 0) {
                 int len = stdout.read(buffer, 0, (avail > BUFFER_SIZE - 1 ? BUFFER_SIZE : avail));
                 strStdout.append(new String(buffer, 0, len));
             }
             while ((avail = stderr.available()) > 0) {
                 int len = stderr.read(buffer, 0, (avail > BUFFER_SIZE - 1 ? BUFFER_SIZE : avail));
                 strStderr.append(new String(buffer, 0, len));
             }
             if (channel.isClosed()) {
                 break;
             }
             try {
                 Thread.sleep(POLL_SLEEP_TIME);
             } catch (Exception ee) {
                 // ignored
             }
         }
         int avail = 0;
         while ((avail = stdout.available()) > 0) {
             int len = stdout.read(buffer, 0, (avail > BUFFER_SIZE - 1 ? BUFFER_SIZE : avail));
             strStdout.append(new String(buffer, 0, len));
         }
         while ((avail = stderr.available()) > 0) {
             int len = stderr.read(buffer, 0, (avail > BUFFER_SIZE - 1 ? BUFFER_SIZE : avail));
             strStderr.append(new String(buffer, 0, len));
         }
     }

     /*
      * (non-Javadoc)
      *
      * @see org.apache.ivy.repository.Repository#list(java.lang.String)
      */
     public List<String> list(String parent) throws IOException {
         Message.debug("SShRepository:list called: " + parent);
         List<String> result = new ArrayList<>();
         Session session = null;
         ChannelExec channel = null;
         session = getSession(parent);
         channel = getExecChannel(session);
         URI parentUri = null;
         try {
             parentUri = new URI(parent);
         } catch (URISyntaxException e) {
             throw new IOException("The uri '" + parent + "' is not valid!", e);
         }
         String fullCmd = replaceArgument(listCommand, parentUri.getPath());
         channel.setCommand(fullCmd);
         StringBuilder stdOut = new StringBuilder();
         StringBuilder stdErr = new StringBuilder();
         readSessionOutput(channel, stdOut, stdErr);
         if (channel.getExitStatus() != 0) {
             Message.error("Ssh ListCommand exited with status != 0");
             Message.error(stdErr.toString());
             return null;
         } else {
             BufferedReader br = new BufferedReader(new StringReader(stdOut.toString()));
             String line = null;
             while ((line = br.readLine()) != null) {
                 result.add(line);
             }
         }
         return result;
     }

     /**
      * @param session Session
      * @return ChannelExec
      */
     private ChannelExec getExecChannel(Session session) throws IOException {
         ChannelExec channel;
         try {
             channel = (ChannelExec) session.openChannel("exec");
         } catch (JSchException e) {
             throw new IOException();
         }
         return channel;
     }

     /**
      * Replace the argument placeholder with argument or append the argument if no placeholder is
      * present
      *
      * @param command
      *            with argument placeholder or not
      * @param argument ditto
      * @return replaced full command
      */
     private String replaceArgument(String command, String argument) {
         String fullCmd;
         if (!command.contains(ARGUMENT_PLACEHOLDER)) {
             fullCmd = command + " " + argument;
         } else {
             fullCmd = command.replaceAll(ARGUMENT_PLACEHOLDER, argument);
         }
         return fullCmd;
     }

     /*
      * (non-Javadoc)
      *
      * @see org.apache.ivy.repository.Repository#put(java.io.File, java.lang.String, boolean)
      */
     public void put(File source, String destination, boolean overwrite) throws IOException {
         Message.debug("SShRepository:put called: " + destination);
         Session session = getSession(destination);

         URI destinationUri = null;
         try {
             destinationUri = new URI(destination);
         } catch (URISyntaxException e) {
             throw new IOException("The uri '" + destination + "' is not valid!", e);
         }

         try {
             String filePath = destinationUri.getPath();
             int lastSep = filePath.lastIndexOf(fileSeparator);
             String path;
             String name;
             if (lastSep == -1) {
                 name = filePath;
                 path = null;
             } else {
                 name = filePath.substring(lastSep + 1);
                 path = filePath.substring(0, lastSep);
             }
             if (!overwrite) {
                 if (checkExistence(filePath, session)) {
                     throw new IOException("destination file exists and overwrite == false");
                 }
             }
             if (path != null) {
                 makePath(path, session);
             }
             Scp myCopy = new Scp(session);
             myCopy.put(source.getCanonicalPath(), path, name, publishPermissions);
         } catch (IOException e) {
             if (session != null) {
                 releaseSession(session, destination);
             }
             throw e;
         } catch (RemoteScpException e) {
             throw new IOException(e.getMessage());
         }
     }

     /**
      * Tries to create a directory path on the target system
      *
      * @param path
      *            to create
      * @param session
      *            to use
      */
     private void makePath(String path, Session session) throws IOException {
         ChannelExec channel = null;
         String trimmed = path;
         try {
             while (trimmed.length() > 0 && trimmed.charAt(trimmed.length() - 1) == fileSeparator) {
                 trimmed = trimmed.substring(0, trimmed.length() - 1);
             }
             if (trimmed.length() == 0 || checkExistence(trimmed, session)) {
                 return;
             }
             int nextSlash = trimmed.lastIndexOf(fileSeparator);
             if (nextSlash > 0) {
                 String parent = trimmed.substring(0, nextSlash);
                 makePath(parent, session);
             }
             channel = getExecChannel(session);
             String mkdir = replaceArgument(createDirCommand, trimmed);
             Message.debug("SShRepository: trying to create path: " + mkdir);
             channel.setCommand(mkdir);
             StringBuilder stdOut = new StringBuilder();
             StringBuilder stdErr = new StringBuilder();
             readSessionOutput(channel, stdOut, stdErr);
         } finally {
             if (channel != null) {
                 channel.disconnect();
             }
         }
     }

     /**
      * check for existence of file or dir on target system
      *
      * @param filePath
      *            to the object to check
      * @param session
      *            to use
      * @return true: object exists, false otherwise
      */
     private boolean checkExistence(String filePath, Session session) throws IOException {
         Message.debug("SShRepository: checkExistence called: " + filePath);
         ChannelExec channel = null;
         channel = getExecChannel(session);
         String fullCmd = replaceArgument(existCommand, filePath);
         channel.setCommand(fullCmd);
         StringBuilder stdOut = new StringBuilder();
         StringBuilder stdErr = new StringBuilder();
         readSessionOutput(channel, stdOut, stdErr);
         return channel.getExitStatus() == 0;
     }

     /*
      * (non-Javadoc)
      *
      * @see org.apache.ivy.repository.Repository#get(java.lang.String, java.io.File)
      */
     public void get(String source, File destination) throws IOException {
         Message.debug("SShRepository:get called: " + source + " to "
                 + destination.getCanonicalPath());
         if (destination.getParentFile() != null) {
             destination.getParentFile().mkdirs();
         }
         Session session = getSession(source);

         URI sourceUri = null;
         try {
             sourceUri = new URI(source);
         } catch (URISyntaxException e) {
             throw new IOException("The uri '" + source + "' is not valid!", e);
         }

         try {
             Scp myCopy = new Scp(session);
             myCopy.get(sourceUri.getPath(), destination.getCanonicalPath());
         } catch (IOException e) {
             if (session != null) {
                 releaseSession(session, source);
             }
             throw e;
         } catch (RemoteScpException e) {
             throw new IOException(e.getMessage());
         }
     }

     /**
      * sets the list command to use for a directory listing listing must be only the filename and
      * each filename on a separate line
      *
      * @param cmd
      *            to use. default is "ls -1"
      */
     public void setListCommand(String cmd) {
         this.listCommand = cmd.trim();
     }

     /**
      * @return the list command to use
      */
     public String getListCommand() {
         return listCommand;
     }

     /**
      * @return the createDirCommand
      */
     public String getCreateDirCommand() {
         return createDirCommand;
     }

     /**
      * @param createDirCommand
      *            the createDirCommand to set
      */
     public void setCreateDirCommand(String createDirCommand) {
         this.createDirCommand = createDirCommand;
     }

     /**
      * @return the existCommand
      */
     public String getExistCommand() {
         return existCommand;
     }

     /**
      * @param existCommand
      *            the existCommand to set
      */
     public void setExistCommand(String existCommand) {
         this.existCommand = existCommand;
     }

     /**
      * The file separator is the separator to use on the target system On a unix system it is '/',
      * but I don't know, how this is solved on different ssh implementations. Using the default
      * might be fine
      *
      * @param fileSeparator
      *            The fileSeparator to use. default '/'
      */
     public void setFileSeparator(char fileSeparator) {
         this.fileSeparator = fileSeparator;
     }

     /**
      * A four digit string (e.g., 0644, see "man chmod", "man open") specifying the permissions of
      * the published files.
      *
      * @param permissions String
      */
     public void setPublishPermissions(String permissions) {
         this.publishPermissions = permissions;
     }

     /**
      * return ssh as scheme use the Resolver type name here? would be nice if it would be static, so
      * we could use SshResolver.getTypeName()
      *
      * @return String
      */
     protected String getRepositoryScheme() {
         return "ssh";
     }

     /**
      * Not really streaming...need to implement a proper streaming approach?
      *
      * @param resource
      *            to stream
      * @return InputStream of the resource data
      * @throws IOException if something goes wrong
      */
     public InputStream openStream(SshResource resource) throws IOException {
         Session session = getSession(resource.getName());
         Scp scp = new Scp(session);
         ByteArrayOutputStream os = new ByteArrayOutputStream();
         try {
             scp.get(resource.getName(), os);
         } catch (IOException e) {
             if (session != null) {
                 releaseSession(session, resource.getName());
             }
             throw e;
         } catch (RemoteScpException e) {
             throw new IOException(e.getMessage());
         }
         return new ByteArrayInputStream(os.toByteArray());
     }
 }
	/*
	* 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
	*
	* https://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.ivy.plugins.repository.ssh;

	import java.io.BufferedReader;
	import java.io.ByteArrayInputStream;
	import java.io.ByteArrayOutputStream;
	import java.io.File;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.StringReader;
	import java.net.URI;
	import java.net.URISyntaxException;
	import java.util.ArrayList;
	import java.util.List;

	import org.apache.ivy.core.settings.TimeoutConstraint;
	import org.apache.ivy.plugins.repository.Resource;
	import org.apache.ivy.util.Message;

	import com.jcraft.jsch.ChannelExec;
	import com.jcraft.jsch.JSchException;
	import com.jcraft.jsch.Session;

	/**
	* Ivy Repository based on SSH
	*/
	public class SshRepository extends AbstractSshBasedRepository {

	private static final int BUFFER_SIZE = 64 * 1024;

	private static final String ARGUMENT_PLACEHOLDER = "%arg";

	private static final int POLL_SLEEP_TIME = 500;

	private char fileSeparator = '/';

	private String listCommand = "ls -1";

	private String existCommand = "ls";

	private String createDirCommand = "mkdir";

	private String publishPermissions = null;

	public SshRepository() {

	}

	public SshRepository(final TimeoutConstraint timeoutConstraint) {
	super(timeoutConstraint);
	}

	/**
	* create a new resource with lazy initializing
	*
	* @param source String
	* @return Resource
	*/
	public Resource getResource(String source) {
	Message.debug("SShRepository:getResource called: " + source);
	return new SshResource(this, source);
	}

	/**
	* Fetch the needed file information for a given file (size, last modification time) and report
	* it back in a SshResource
	*
	* @param source
	* ssh uri for the file to get info for
	* @return SshResource filled with the needed information
	* @see org.apache.ivy.plugins.repository.Repository#getResource(java.lang.String)
	*/
	public SshResource resolveResource(String source) {
	Message.debug("SShRepository:resolveResource called: " + source);
	SshResource result = null;
	Session session = null;
	try {
	session = getSession(source);
	Scp myCopy = new Scp(session);
	Scp.FileInfo fileInfo = myCopy.getFileinfo(new URI(source).getPath());
	result = new SshResource(this, source, true, fileInfo.getLength(),
	fileInfo.getLastModified());
	} catch (IOException \| URISyntaxException e) {
	if (session != null) {
	releaseSession(session, source);
	}
	result = new SshResource();
	} catch (RemoteScpException e) {
	result = new SshResource();
	}
	Message.debug("SShRepository:resolveResource end.");
	return result;
	}

	/**
	* Reads out the output of a ssh session exec
	*
	* @param channel
	* Channel to read from
	* @param strStdout
	* StringBuilder that receives Session Stdout output
	* @param strStderr
	* StringBuilder that receives Session Stderr output
	* @throws IOException
	* in case of trouble with the network
	*/
	private void readSessionOutput(ChannelExec channel, StringBuilder strStdout,
	StringBuilder strStderr) throws IOException {
	InputStream stdout = channel.getInputStream();
	InputStream stderr = channel.getErrStream();

	try {
	channel.connect();
	} catch (JSchException jsche) {
	throw new IOException("Channel connection problems", jsche);
	}

	byte[] buffer = new byte[BUFFER_SIZE];
	while (true) {
	int avail = 0;
	while ((avail = stdout.available()) > 0) {
	int len = stdout.read(buffer, 0, (avail > BUFFER_SIZE - 1 ? BUFFER_SIZE : avail));
	strStdout.append(new String(buffer, 0, len));
	}
	while ((avail = stderr.available()) > 0) {
	int len = stderr.read(buffer, 0, (avail > BUFFER_SIZE - 1 ? BUFFER_SIZE : avail));
	strStderr.append(new String(buffer, 0, len));
	}
	if (channel.isClosed()) {
	break;
	}
	try {
	Thread.sleep(POLL_SLEEP_TIME);
	} catch (Exception ee) {
	// ignored
	}
	}
	int avail = 0;
	while ((avail = stdout.available()) > 0) {
	int len = stdout.read(buffer, 0, (avail > BUFFER_SIZE - 1 ? BUFFER_SIZE : avail));
	strStdout.append(new String(buffer, 0, len));
	}
	while ((avail = stderr.available()) > 0) {
	int len = stderr.read(buffer, 0, (avail > BUFFER_SIZE - 1 ? BUFFER_SIZE : avail));
	strStderr.append(new String(buffer, 0, len));
	}
	}

	/*
	* (non-Javadoc)
	*
	* @see org.apache.ivy.repository.Repository#list(java.lang.String)
	*/
	public List<String> list(String parent) throws IOException {
	Message.debug("SShRepository:list called: " + parent);
	List<String> result = new ArrayList<>();
	Session session = null;
	ChannelExec channel = null;
	session = getSession(parent);
	channel = getExecChannel(session);
	URI parentUri = null;
	try {
	parentUri = new URI(parent);
	} catch (URISyntaxException e) {
	throw new IOException("The uri '" + parent + "' is not valid!", e);
	}
	String fullCmd = replaceArgument(listCommand, parentUri.getPath());
	channel.setCommand(fullCmd);
	StringBuilder stdOut = new StringBuilder();
	StringBuilder stdErr = new StringBuilder();
	readSessionOutput(channel, stdOut, stdErr);
	if (channel.getExitStatus() != 0) {
	Message.error("Ssh ListCommand exited with status != 0");
	Message.error(stdErr.toString());
	return null;
	} else {
	BufferedReader br = new BufferedReader(new StringReader(stdOut.toString()));
	String line = null;
	while ((line = br.readLine()) != null) {
	result.add(line);
	}
	}
	return result;
	}

	/**
	* @param session Session
	* @return ChannelExec
	*/
	private ChannelExec getExecChannel(Session session) throws IOException {
	ChannelExec channel;
	try {
	channel = (ChannelExec) session.openChannel("exec");
	} catch (JSchException e) {
	throw new IOException();
	}
	return channel;
	}

	/**
	* Replace the argument placeholder with argument or append the argument if no placeholder is
	* present
	*
	* @param command
	* with argument placeholder or not
	* @param argument ditto
	* @return replaced full command
	*/
	private String replaceArgument(String command, String argument) {
	String fullCmd;
	if (!command.contains(ARGUMENT_PLACEHOLDER)) {
	fullCmd = command + " " + argument;
	} else {
	fullCmd = command.replaceAll(ARGUMENT_PLACEHOLDER, argument);
	}
	return fullCmd;
	}

	/*
	* (non-Javadoc)
	*
	* @see org.apache.ivy.repository.Repository#put(java.io.File, java.lang.String, boolean)
	*/
	public void put(File source, String destination, boolean overwrite) throws IOException {
	Message.debug("SShRepository:put called: " + destination);
	Session session = getSession(destination);

	URI destinationUri = null;
	try {
	destinationUri = new URI(destination);
	} catch (URISyntaxException e) {
	throw new IOException("The uri '" + destination + "' is not valid!", e);
	}

	try {
	String filePath = destinationUri.getPath();
	int lastSep = filePath.lastIndexOf(fileSeparator);
	String path;
	String name;
	if (lastSep == -1) {
	name = filePath;
	path = null;
	} else {
	name = filePath.substring(lastSep + 1);
	path = filePath.substring(0, lastSep);
	}
	if (!overwrite) {
	if (checkExistence(filePath, session)) {
	throw new IOException("destination file exists and overwrite == false");
	}
	}
	if (path != null) {
	makePath(path, session);
	}
	Scp myCopy = new Scp(session);
	myCopy.put(source.getCanonicalPath(), path, name, publishPermissions);
	} catch (IOException e) {
	if (session != null) {
	releaseSession(session, destination);
	}
	throw e;
	} catch (RemoteScpException e) {
	throw new IOException(e.getMessage());
	}
	}

	/**
	* Tries to create a directory path on the target system
	*
	* @param path
	* to create
	* @param session
	* to use
	*/
	private void makePath(String path, Session session) throws IOException {
	ChannelExec channel = null;
	String trimmed = path;
	try {
	while (trimmed.length() > 0 && trimmed.charAt(trimmed.length() - 1) == fileSeparator) {
	trimmed = trimmed.substring(0, trimmed.length() - 1);
	}
	if (trimmed.length() == 0 \|\| checkExistence(trimmed, session)) {
	return;
	}
	int nextSlash = trimmed.lastIndexOf(fileSeparator);
	if (nextSlash > 0) {
	String parent = trimmed.substring(0, nextSlash);
	makePath(parent, session);
	}
	channel = getExecChannel(session);
	String mkdir = replaceArgument(createDirCommand, trimmed);
	Message.debug("SShRepository: trying to create path: " + mkdir);
	channel.setCommand(mkdir);
	StringBuilder stdOut = new StringBuilder();
	StringBuilder stdErr = new StringBuilder();
	readSessionOutput(channel, stdOut, stdErr);
	} finally {
	if (channel != null) {
	channel.disconnect();
	}
	}
	}

	/**
	* check for existence of file or dir on target system
	*
	* @param filePath
	* to the object to check
	* @param session
	* to use
	* @return true: object exists, false otherwise
	*/
	private boolean checkExistence(String filePath, Session session) throws IOException {
	Message.debug("SShRepository: checkExistence called: " + filePath);
	ChannelExec channel = null;
	channel = getExecChannel(session);
	String fullCmd = replaceArgument(existCommand, filePath);
	channel.setCommand(fullCmd);
	StringBuilder stdOut = new StringBuilder();
	StringBuilder stdErr = new StringBuilder();
	readSessionOutput(channel, stdOut, stdErr);
	return channel.getExitStatus() == 0;
	}

	/*
	* (non-Javadoc)
	*
	* @see org.apache.ivy.repository.Repository#get(java.lang.String, java.io.File)
	*/
	public void get(String source, File destination) throws IOException {
	Message.debug("SShRepository:get called: " + source + " to "
	+ destination.getCanonicalPath());
	if (destination.getParentFile() != null) {
	destination.getParentFile().mkdirs();
	}
	Session session = getSession(source);

	URI sourceUri = null;
	try {
	sourceUri = new URI(source);
	} catch (URISyntaxException e) {
	throw new IOException("The uri '" + source + "' is not valid!", e);
	}

	try {
	Scp myCopy = new Scp(session);
	myCopy.get(sourceUri.getPath(), destination.getCanonicalPath());
	} catch (IOException e) {
	if (session != null) {
	releaseSession(session, source);
	}
	throw e;
	} catch (RemoteScpException e) {
	throw new IOException(e.getMessage());
	}
	}

	/**
	* sets the list command to use for a directory listing listing must be only the filename and
	* each filename on a separate line
	*
	* @param cmd
	* to use. default is "ls -1"
	*/
	public void setListCommand(String cmd) {
	this.listCommand = cmd.trim();
	}

	/**
	* @return the list command to use
	*/
	public String getListCommand() {
	return listCommand;
	}

	/**
	* @return the createDirCommand
	*/
	public String getCreateDirCommand() {
	return createDirCommand;
	}

	/**
	* @param createDirCommand
	* the createDirCommand to set
	*/
	public void setCreateDirCommand(String createDirCommand) {
	this.createDirCommand = createDirCommand;
	}

	/**
	* @return the existCommand
	*/
	public String getExistCommand() {
	return existCommand;
	}

	/**
	* @param existCommand
	* the existCommand to set
	*/
	public void setExistCommand(String existCommand) {
	this.existCommand = existCommand;
	}

	/**
	* The file separator is the separator to use on the target system On a unix system it is '/',
	* but I don't know, how this is solved on different ssh implementations. Using the default
	* might be fine
	*
	* @param fileSeparator
	* The fileSeparator to use. default '/'
	*/
	public void setFileSeparator(char fileSeparator) {
	this.fileSeparator = fileSeparator;
	}

	/**
	* A four digit string (e.g., 0644, see "man chmod", "man open") specifying the permissions of
	* the published files.
	*
	* @param permissions String
	*/
	public void setPublishPermissions(String permissions) {
	this.publishPermissions = permissions;
	}

	/**
	* return ssh as scheme use the Resolver type name here? would be nice if it would be static, so
	* we could use SshResolver.getTypeName()
	*
	* @return String
	*/
	protected String getRepositoryScheme() {
	return "ssh";
	}

	/**
	* Not really streaming...need to implement a proper streaming approach?
	*
	* @param resource
	* to stream
	* @return InputStream of the resource data
	* @throws IOException if something goes wrong
	*/
	public InputStream openStream(SshResource resource) throws IOException {
	Session session = getSession(resource.getName());
	Scp scp = new Scp(session);
	ByteArrayOutputStream os = new ByteArrayOutputStream();
	try {
	scp.get(resource.getName(), os);
	} catch (IOException e) {
	if (session != null) {
	releaseSession(session, resource.getName());
	}
	throw e;
	} catch (RemoteScpException e) {
	throw new IOException(e.getMessage());
	}
	return new ByteArrayInputStream(os.toByteArray());
	}
	}