Como recuperar um arquivo de um servidor via SFTP?
Pergunta
Estou tentando recuperar um arquivo de um servidor usando SFTP (em vez de FTPS) usando Java.Como posso fazer isso?
Solução
Outra opção é considerar olhar para o Biblioteca JSch.JSch parece ser a biblioteca preferida para alguns grandes projetos de código aberto, incluindo Eclipse, Ant e Apache Commons HttpClient, entre outros.
Ele suporta logins de usuário/senha e baseados em certificado, bem como uma série de outros recursos SSH2 deliciosos.
Aqui está uma recuperação remota simples de arquivo por SFTP.O tratamento de erros fica como exercício para o leitor :-)
JSch jsch = new JSch();
String knownHostsFilename = "/home/username/.ssh/known_hosts";
jsch.setKnownHosts( knownHostsFilename );
Session session = jsch.getSession( "remote-username", "remote-host" );
{
// "interactive" version
// can selectively update specified known_hosts file
// need to implement UserInfo interface
// MyUserInfo is a swing implementation provided in
// examples/Sftp.java in the JSch dist
UserInfo ui = new MyUserInfo();
session.setUserInfo(ui);
// OR non-interactive version. Relies in host key being in known-hosts file
session.setPassword( "remote-password" );
}
session.connect();
Channel channel = session.openChannel( "sftp" );
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.get("remote-file", "local-file" );
// OR
InputStream in = sftpChannel.get( "remote-file" );
// process inputstream as needed
sftpChannel.exit();
session.disconnect();
Outras dicas
Aqui está o código-fonte completo de um exemplo usando JSch sem ter que se preocupar com a verificação da chave ssh.
import com.jcraft.jsch.*;
public class TestJSch {
public static void main(String args[]) {
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession("username", "127.0.0.1", 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword("password");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.get("remotefile.txt", "localfile.txt");
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
}
}
Abaixo está um exemplo usando Apache Common VFS:
FileSystemOptions fsOptions = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(fsOptions, "no");
FileSystemManager fsManager = VFS.getManager();
String uri = "sftp://user:password@host:port/absolute-path";
FileObject fo = fsManager.resolveFile(uri, fsOptions);
Essa foi a solução que encontreihttp://sourceforge.net/projects/sshtools/ (a maior parte do tratamento de erros foi omitida para maior clareza).Este é um trecho de meu blog
SshClient ssh = new SshClient();
ssh.connect(host, port);
//Authenticate
PasswordAuthenticationClient passwordAuthenticationClient = new PasswordAuthenticationClient();
passwordAuthenticationClient.setUsername(userName);
passwordAuthenticationClient.setPassword(password);
int result = ssh.authenticate(passwordAuthenticationClient);
if(result != AuthenticationProtocolState.COMPLETE){
throw new SFTPException("Login to " + host + ":" + port + " " + userName + "/" + password + " failed");
}
//Open the SFTP channel
SftpClient client = ssh.openSftpClient();
//Send the file
client.put(filePath);
//disconnect
client.quit();
ssh.disconnect();
Uma boa abstração em cima do Jsch é o Apache commons-vfs que oferece uma API de sistema de arquivos virtual que torna o acesso e a gravação de arquivos SFTP quase transparentes.Funcionou bem para nós.
Há uma boa comparação das três bibliotecas Java maduras para SFTP: Commons VFS, SSHJ e JSch
Resumindo, o SSHJ tem a API mais clara e é a melhor delas se você não precisar de outro suporte de armazenamento fornecido pelo Commons VFS.
Aqui está o exemplo SSHJ editado de GitHub:
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts(); // or, to skip host verification: ssh.addHostKeyVerifier(new PromiscuousVerifier())
ssh.connect("localhost");
try {
ssh.authPassword("user", "password"); // or ssh.authPublickey(System.getProperty("user.name"))
final SFTPClient sftp = ssh.newSFTPClient();
try {
sftp.get("test_file", "/tmp/test.tmp");
} finally {
sftp.close();
}
} finally {
ssh.disconnect();
}
Biblioteca SFTP do Apache Commons
Arquivo de propriedades java comum para todos os exemplos
endereçoservidor=111.222.333.444
userId=meuUserId
senha = minha senha
remoteDirectory=produtos/
diretório local=importar/
Carregar arquivo para servidor remoto usando SFTP
import java.io.File;
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.Selectors;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class SendMyFiles {
static Properties props;
public static void main(String[] args) {
SendMyFiles sendMyFiles = new SendMyFiles();
if (args.length < 1)
{
System.err.println("Usage: java " + sendMyFiles.getClass().getName()+
" Properties_file File_To_FTP ");
System.exit(1);
}
String propertiesFile = args[0].trim();
String fileToFTP = args[1].trim();
sendMyFiles.startFTP(propertiesFile, fileToFTP);
}
public boolean startFTP(String propertiesFilename, String fileToFTP){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
String localDirectory = props.getProperty("localDirectory").trim();
//check if the file exists
String filepath = localDirectory + fileToFTP;
File file = new File(filepath);
if (!file.exists())
throw new RuntimeException("Error. Local file not found");
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "@" + serverAddress + "/" +
remoteDirectory + fileToFTP;
// Create local file object
FileObject localFile = manager.resolveFile(file.getAbsolutePath());
// Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
// Copy local file to sftp server
remoteFile.copyFrom(localFile, Selectors.SELECT_SELF);
System.out.println("File upload successful");
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
Baixe o arquivo do servidor remoto usando SFTP
import java.io.File;
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.Selectors;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class GetMyFiles {
static Properties props;
public static void main(String[] args) {
GetMyFiles getMyFiles = new GetMyFiles();
if (args.length < 1)
{
System.err.println("Usage: java " + getMyFiles.getClass().getName()+
" Properties_filename File_To_Download ");
System.exit(1);
}
String propertiesFilename = args[0].trim();
String fileToDownload = args[1].trim();
getMyFiles.startFTP(propertiesFilename, fileToDownload);
}
public boolean startFTP(String propertiesFilename, String fileToDownload){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
String localDirectory = props.getProperty("localDirectory").trim();
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "@" + serverAddress + "/" +
remoteDirectory + fileToDownload;
// Create local file object
String filepath = localDirectory + fileToDownload;
File file = new File(filepath);
FileObject localFile = manager.resolveFile(file.getAbsolutePath());
// Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
// Copy local file to sftp server
localFile.copyFrom(remoteFile, Selectors.SELECT_SELF);
System.out.println("File download successful");
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
Exclua um arquivo no servidor remoto usando SFTP
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class DeleteRemoteFile {
static Properties props;
public static void main(String[] args) {
DeleteRemoteFile getMyFiles = new DeleteRemoteFile();
if (args.length < 1)
{
System.err.println("Usage: java " + getMyFiles.getClass().getName()+
" Properties_filename File_To_Delete ");
System.exit(1);
}
String propertiesFilename = args[0].trim();
String fileToDownload = args[1].trim();
getMyFiles.startFTP(propertiesFilename, fileToDownload);
}
public boolean startFTP(String propertiesFilename, String fileToDownload){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "@" + serverAddress + "/" +
remoteDirectory + fileToDownload;
//Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
//Check if the file exists
if(remoteFile.exists()){
remoteFile.delete();
System.out.println("File delete successful");
}
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
hierynomus/sshj tem uma implementação completa do SFTP versão 3 (o que o OpenSSH implementa)
Código de exemplo de SFTPUpload.java
package net.schmizz.sshj.examples;
import net.schmizz.sshj.SSHClient;
import net.schmizz.sshj.sftp.SFTPClient;
import net.schmizz.sshj.xfer.FileSystemFile;
import java.io.File;
import java.io.IOException;
/** This example demonstrates uploading of a file over SFTP to the SSH server. */
public class SFTPUpload {
public static void main(String[] args)
throws IOException {
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts();
ssh.connect("localhost");
try {
ssh.authPublickey(System.getProperty("user.name"));
final String src = System.getProperty("user.home") + File.separator + "test_file";
final SFTPClient sftp = ssh.newSFTPClient();
try {
sftp.put(new FileSystemFile(src), "/tmp");
} finally {
sftp.close();
}
} finally {
ssh.disconnect();
}
}
}
A biblioteca JSch é a biblioteca poderosa que pode ser usada para ler arquivos do servidor SFTP.Abaixo está o código testado para ler o arquivo do local SFTP linha por linha
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession("user", "127.0.0.1", 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword("password");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
InputStream stream = sftpChannel.get("/usr/home/testfile.txt");
try {
BufferedReader br = new BufferedReader(new InputStreamReader(stream));
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
} catch (IOException io) {
System.out.println("Exception occurred during reading file from SFTP server due to " + io.getMessage());
io.getMessage();
} catch (Exception e) {
System.out.println("Exception occurred during reading file from SFTP server due to " + e.getMessage());
e.getMessage();
}
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
Por favor consulte o blog para todo o programa.
Andy, para deletar arquivo no sistema remoto você precisa usar (channelExec)
do JSch e passe comandos unix/linux para excluí-lo.
Tentar edtFTPj/PRO, uma biblioteca cliente SFTP madura e robusta que oferece suporte a pools de conexões e operações assíncronas.Também suporta FTP e FTPS para que todas as bases para transferência segura de arquivos sejam cobertas.
Encontrei um exemplo completo de trabalho para SFTP em java usando API JSCHhttp://kodehelp.com/java-program-for-uploading-file-to-sftp-server/
Embora as respostas acima tenham sido muito úteis, passei um dia fazendo-as funcionar, enfrentando várias exceções como "canal quebrado", "chave rsa desconhecida" e "pacote corrompido".
Abaixo está uma classe funcional reutilizável para SFTP FILES UPLOAD/DOWNLOAD usando a biblioteca JSch.
Carregar uso:
SFTPFileCopy upload = new SFTPFileCopy(true, /path/to/sourcefile.png", /path/to/destinationfile.png");
Uso de download:
SFTPFileCopy download = new SFTPFileCopy(false, "/path/to/sourcefile.png", "/path/to/destinationfile.png");
O código da classe:
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.UIKeyboardInteractive;
import com.jcraft.jsch.UserInfo;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import javax.swing.JOptionPane;
import menue.Menue;
public class SFTPFileCopy1 {
public SFTPFileCopy1(boolean upload, String sourcePath, String destPath) throws FileNotFoundException, IOException {
Session session = null;
Channel channel = null;
ChannelSftp sftpChannel = null;
try {
JSch jsch = new JSch();
//jsch.setKnownHosts("/home/user/.putty/sshhostkeys");
session = jsch.getSession("login", "mysite.com", 22);
session.setPassword("password");
UserInfo ui = new MyUserInfo() {
public void showMessage(String message) {
JOptionPane.showMessageDialog(null, message);
}
public boolean promptYesNo(String message) {
Object[] options = {"yes", "no"};
int foo = JOptionPane.showOptionDialog(null,
message,
"Warning",
JOptionPane.DEFAULT_OPTION,
JOptionPane.WARNING_MESSAGE,
null, options, options[0]);
return foo == 0;
}
};
session.setUserInfo(ui);
session.setConfig("StrictHostKeyChecking", "no");
session.connect();
channel = session.openChannel("sftp");
channel.setInputStream(System.in);
channel.setOutputStream(System.out);
channel.connect();
sftpChannel = (ChannelSftp) channel;
if (upload) { // File upload.
byte[] bufr = new byte[(int) new File(sourcePath).length()];
FileInputStream fis = new FileInputStream(new File(sourcePath));
fis.read(bufr);
ByteArrayInputStream fileStream = new ByteArrayInputStream(bufr);
sftpChannel.put(fileStream, destPath);
fileStream.close();
} else { // File download.
byte[] buffer = new byte[1024];
BufferedInputStream bis = new BufferedInputStream(sftpChannel.get(sourcePath));
OutputStream os = new FileOutputStream(new File(destPath));
BufferedOutputStream bos = new BufferedOutputStream(os);
int readCount;
while ((readCount = bis.read(buffer)) > 0) {
bos.write(buffer, 0, readCount);
}
bis.close();
bos.close();
}
} catch (Exception e) {
System.out.println(e);
} finally {
if (sftpChannel != null) {
sftpChannel.exit();
}
if (channel != null) {
channel.disconnect();
}
if (session != null) {
session.disconnect();
}
}
}
public static abstract class MyUserInfo
implements UserInfo, UIKeyboardInteractive {
public String getPassword() {
return null;
}
public boolean promptYesNo(String str) {
return false;
}
public String getPassphrase() {
return null;
}
public boolean promptPassphrase(String message) {
return false;
}
public boolean promptPassword(String message) {
return false;
}
public void showMessage(String message) {
}
public String[] promptKeyboardInteractive(String destination,
String name,
String instruction,
String[] prompt,
boolean[] echo) {
return null;
}
}
}
Você também tem JFileUpload com complemento SFTP (Java também):http://www.jfileupload.com/products/sftp/index.html
Eu uso uma API SFTP chamada Zehon, é ótima, muito fácil de usar e com muitos exemplos de código.Aqui está o site http://www.zehon.com
A melhor solução que encontrei é Paramiko.Existe uma versão Java.