spring integration sftp mainframe :failed to write file; nested exception is 3: Permission denied

Question

I am trying to sft file to mainframe using spring integration sftp:outbound-gateway: this is configuration:

Answer 1

To follow up on what Artem pointed out, when sFTPing to, for example, a cloud Axway sFTP server, where I was told that the current working directory was "/"

First, I used a terminal sftp client:

$ sftp username@mft-xxx.axwaycloud.com
sftp> pwd
Remote working directory: /

This isn't the root /, but the chrooted directory so that I have no way to determine what the absolute path is. The below code String ftpRemoteDestinationPath = "/" + tempFile.getName(); works though in this situation:

    if (tempFile.exists()) {

        try {
            axwaySftpRemoteFileTemplate.execute((SessionCallback) session -> {

                String ftpRemoteDestinationPath = "/" + tempFile.getName();

                logger.info("FTP local file residing on server: [" + tempFile.getAbsolutePath() + "]");

                InputStream targetStream = new FileInputStream(tempFile);

                logger.debug("sftp uploading file: [" + tempFile.getName() + "] using channel connected to an sftp server :[" + session.getClientInstance().toString() + "]");
                session.write(targetStream, ftpRemoteDestinationPath);

                return null;
            });

        } catch (Exception e) {
            logger.error("Could not send file per SFTP: " + e);

            throw new SomeRuntimeSftpException("Error FTPing file " + tempFile.getAbsolutePath() + " " + e.getMessage());
        }
        finally {
            tempFile.delete();
        }
    }