How to copy a file from ftp server to local directory using sftp and spring boot,Java - spring-boot

Question

I have codes for Inbound and Outbound channel adapter over SFTP. I want to call those method via spring boot scheduler not using polling. Looking for example how to call resultFileHandler() method
public class SftpConfig {
#Value("${nodephone.directory.sftp.host}")
private String sftpHost;
#Value("${nodephone.directory.sftp.port}")
private int sftpPort;
#Value("${nodephone.directory.sftp.user}")
private String sftpUser;
#Value("${nodephone.directory.sftp.password}")
private String sftpPasword;
#Value("${nodephone.directory.sftp.remote.directory.download}")
private String sftpRemoteDirectoryDownload;
#Value("${nodephone.directory.sftp.remote.directory.upload}")
private String sftpRemoteDirectoryUpload;
#Value("${nodephone.directory.sftp.remote.directory.filter}")
private String sftpRemoteDirectoryFilter;
#Value("${nodephone.directory.sftp.remote.directory.localDirectory}")
private String sftpLocalDirectory;
// private FtpOrderRequestHandler handler;
#Bean
public SessionFactory<LsEntry> sftpSessionFactory() {
DefaultSftpSessionFactory factory = new DefaultSftpSessionFactory(true);
factory.setHost(sftpHost);
factory.setPort(sftpPort);
factory.setUser(sftpUser);
factory.setPassword(sftpPasword);
factory.setAllowUnknownKeys(true);
return new CachingSessionFactory<LsEntry>(factory);
}
#Bean
public SftpInboundFileSynchronizer sftpInboundFileSynchronizer() {
SftpInboundFileSynchronizer fileSynchronizer = new SftpInboundFileSynchronizer(sftpSessionFactory());
fileSynchronizer.setDeleteRemoteFiles(true);
fileSynchronizer.setRemoteDirectory(sftpRemoteDirectoryDownload);
fileSynchronizer.setFilter(new SftpSimplePatternFileListFilter(sftpRemoteDirectoryFilter));
return fileSynchronizer;
}
#Bean
#InboundChannelAdapter(channel = "fromSftpChannel", poller = #Poller(cron = "0/5 * * * * *"))
public MessageSource<File> sftpMessageSource() {
SftpInboundFileSynchronizingMessageSource source = new SftpInboundFileSynchronizingMessageSource(
sftpInboundFileSynchronizer());
source.setAutoCreateLocalDirectory(true);
source.setLocalFilter(new AcceptOnceFileListFilter<File>());
source.setLocalDirectory(new File("/local"));
return source;
}
#Bean
#ServiceActivator(inputChannel = "fromSftpChannel")
public MessageHandler resultFileHandler() {
return new MessageHandler() {
#Override
public void handleMessage(Message<?> message) throws MessagingException {
System.out.println("********************** " + message.getPayload());
}
};
}
I have tested with Configuration annotation and it reads the file from the server, but I want to run this from Cron instead of polling, how do I call the method resultFileHandler()

Answer 1

I've never done this using Spring Integration in any production code although I did something like below, to download files from remote servers using sftp/ftp.
I'm only using the SftpOutboundGateway (there could be better ways), to call the "mget" method and fetch the payload (file).
#Configuration
#ConfigurationProperties(prefix = "sftp")
#Setter
#Getter
#EnableIntegration
public class RemoteFileConfiguration {
private String clients;
private String hosts;
private int ports;
private String users;
private String passwords;
#Bean(name = "clientSessionFactory")
public SessionFactory<LsEntry> clientSessionFactory() {
DefaultSftpSessionFactory sf = new DefaultSftpSessionFactory();
sf.setHost(hosts);
sf.setPort(ports);
sf.setUser(users);
sf.setPassword(passwords);
sf.setAllowUnknownKeys(true);
return new CachingSessionFactory<>(sf);
}
#Bean
#ServiceActivator(inputChannel = "sftpChannel")
public MessageHandler clientMessageHandler() {
SftpOutboundGateway sftpOutboundGateway = new SftpOutboundGateway(
clientSessionFactory(), "mget", "payload");
sftpOutboundGateway.setAutoCreateLocalDirectory(true);
sftpOutboundGateway.setLocalDirectory(new File("/users/localPath/client/INPUT/"));
sftpOutboundGateway.setFileExistsMode(FileExistsMode.REPLACE_IF_MODIFIED);
sftpOutboundGateway.setFilter(new AcceptOnceFileListFilter<>());
return sftpOutboundGateway;
}
}
#MessagingGateway
public interface SFTPGateway {
#Gateway(requestChannel = "sftpChannel")
List<File> get(String dir);
}
To ensure we use cron to execute this, I have used a Tasklet which is executed by Spring Batch, when I need it to be using a cron expression.
#Slf4j
#Getter
#Setter
public class RemoteFileInboundTasklet implements Tasklet {
private RemoteFileTemplate remoteFileTemplate;
private String remoteClientDir;
private String clientName;
private SFTPGateway sftpGateway;
#Override
public RepeatStatus execute(StepContribution stepContribution, ChunkContext chunkContext)
throws Exception {
List<File> files = sftpGateway.get(remoteClientDir);
if (CollectionUtils.isEmpty(files)) {
log.warn("No file was downloaded for client {}.", clientName);
return RepeatStatus.FINISHED;
}
log.info("Total file: {}", files.size());
return RepeatStatus.FINISHED;
}
}
NOTE: If you don't want to use Batch's Tasklet, you can use your #Component class and inject the Gateway to call "get" method.
#Autowired
private SFTPGateway sftpGateway;