SFTP Promise Wrapper for ssh2

Support basic SFTP transaction with promises, specifically for fronting SFTP with a web based API using something like Koa

Each request will create a new conneciton and close it when finished, this is by design as its intended to be used in stateless web applications. As such care should exercised when using on high traffic systems to avoid too many connections to SFTP server and general connection overhead.

The current streams implementation requires supplying either readable or writable streams and do not return promises with streams like the getBuffer method. This is to support non-presistent connections which would drop if a stream was returned on the promise resolve.

One connection per call

var config = {host: 'localhost', username: 'user', password: 'pass' };
var SFTPClient = require('sftp-promises');
var sftp = new SFTPClient(config);
     
sftp.ls('~/').then(function(list) { console.log(list) })

Persistent Session calls (Experimental)

var config = {host: 'localhost', username: 'user', password: 'pass' };
var SFTPClient = require('sftp-promises');
var sftp = new SFTPClient();

// get session
var session = sftp.session(config).then(function(ftpSession) { session = ftpSession })
...code to ensure session is ready...  
sftp.ls('~/', session).then(function(list) { console.log(list) })

// close socket
session.end()

config options are the same as ssh2 config options.

All calls take an optional ssh2 Connction object as the final arguement for using persistent session.

sftp.stat(<string>remote_path, [ssh2.Connection]session) returns a promise with on object containing path attributes
sftp.ls(<string>remote_path, [ssh2.Connection]session) returns a promise with an object descibing the path
sftp.getBuffer(<string>remote_path, [ssh2.Connection]session) returns a promise with a buffer containing the file contents
sftp.putBuffer(<Buffer>data, <string>remote_path, [ssh2.Connection]session) returns a promise with a boolean, true if successful
sftp.get(<string>remote_path, <string>local_path, [ssh2.Connection]session) returns a promise with a boolean, true if successful
sftp.put(<string>local_path, <string>remote_path, [ssh2.Connection]session) returns a promise with a boolean, true if successful
sftp.rm(<string>location, [ssh2.Connection]session) returns a promise with a boolean, true if successful
sftp.mv(<string>src, <string>dest, [ssh2.Connection]session) returns a promise with a boolean, true if successful sftp.mkdir(<string>path, [ssh2.Connection]session) returns a promise with a boolean, true if successful sftp.rmdir(<string>path, [ssh2.Connection]session) returns a promise with a boolean, true if successful sftp.getStream(<string>path, writableStream, [ssh2.Connection]session) returns a promise with a boolean, true if stream write completed sftp.putStream(<string>path, writableStream, [ssh2.Connection]session) returns a promise with a boolean, true is stream write completed

• have test rely on ssh2.server instead of local ssh server