Spring Integration - Use filename with gateway - spring

Question

I have a problem with spring integration.
I want to make a request on an ftp server to retrieve the name of a file
(at the command line: ls "filename")
But I cannot recover the file name dynamically.
I understood that there was a story with payload or header but I can not
This is what I have:
Review my controller, I use this :
private FtpConfig.MyGateway gateway;
...
gateway.fichierExist(filename);
in my FTP file :
#Bean
public SessionFactory<FTPFile> ftpSessionFactory() {
DefaultFtpSessionFactory sf = new DefaultFtpSessionFactory();
sf.setHost("");
sf.setPort(21);
sf.setUsername("");
sf.setPassword("");
return new CachingSessionFactory<FTPFile>(sf);
}
#Bean
#ServiceActivator(inputChannel = "ftpChannelExist")
public MessageHandler handler2() {
FtpOutboundGateway ftpOutboundGateway =
new FtpOutboundGateway(ftpSessionFactory(), "ls");
ftpOutboundGateway.setOptions("-a -1")
FtpSimplePatternFileListFilter filter = new FtpSimplePatternFileListFilter("filename"); //on filtre sur le nom
return ftpOutboundGateway;
}
#MessagingGateway
public interface MyGateway {
#Gateway(requestChannel = "ftpChannelExist")
ArrayList<String> fichierExist(String filename);
}
I tried with header too, but I can not do anything ...
Thanks.
(Sorry for my english, i'm french)

Answer 1

See LS command description in the Reference Manual:
In addition, filename filtering is provided, in the same manner as the inbound-channel-adapter.
The message payload resulting from an ls operation is a list of file names, or a list of FileInfo objects. These objects provide information such as modified time, permissions etc.
The remote directory that the ls command acted on is provided in the file_remoteDirectory header.
What you are missing in your configuration is a fact of the remote directory to fetch files from. Typically we suggest to have such a directory in the payload as you do with your fichierExist(String filename) and configure the third ctor arg for the FtpOutboundGateway:
FtpOutboundGateway ftpOutboundGateway =
new FtpOutboundGateway(ftpSessionFactory(), "ls", "payload");
According the logic in the FtpOutboundGateway that expression is serving as a source for the remote directory in the LS command. In your case this one is going to be an argument of your fichierExist(String filename) gateway.
You indeed can use there a FtpSimplePatternFileListFilter, but be sure to specify a proper pattern to filter remote files.
In the end the names of the remote files in the requested directory, after filtering are going to be returned to the ArrayList<String> of your gateway. That's correct.
Otherwise your question isn't clear.

Answer 2

Thanks for your reply.
I have change my FtpOutboundGateway for add "payload" but I can't use payload for my FtpSimplePatternFileListFilter.
I've try :
FtpSimplePatternFileListFilter filter = new FtpSimplePatternFileListFilter("filename");
FtpSimplePatternFileListFilter filter = new FtpSimplePatternFileListFilter("payload");
FtpSimplePatternFileListFilter filter = new FtpSimplePatternFileListFilter("payload.filename");
FtpSimplePatternFileListFilter filter = new FtpSimplePatternFileListFilter("payload['filename']");