I know this response is a little late however NetSuite just replaced SFTP.
If you have access to NetSuite SuiteAnswers, check out the link below.
https://netsuite.custhelp.com/app/answers/detail/a_id/51361
/**
*@NApiVersion 2.x
*/
require(['N/sftp', 'N/file'],
function(sftp, file) {
var myPwdGuid = "B34672495064525E5D65032D63B52301";
var myHostKey = "AAA1234567890Q=";
var connection = sftp.createConnection({
username: 'myuser',
passwordGuid: myPwdGuid,
url: 'host.somewhere.com',
directory: 'myuser/wheres/my/file',
hostKey: myHostKey
});
var myFileToUpload = file.create({
name: 'originalname.js',
fileType: file.fileType.PLAINTEXT,
contents: 'I am a test file. Hear me roar.'
});
connection.upload({
directory: 'relative/path/to/remote/dir',
filename: 'newFileNameOnServer.js',
file: myFileToUpload,
replaceExisting: true
});
var downloadedFile = connection.download({
directory: 'relative/path/to/file',
filename: 'downloadMe.js'
});
});