Basic FTP server with awareness of file paths

ftp_server.py

from twisted.protocols.ftp import FTP, FTPFactory, FTPRealm
from twisted.cred.portal import Portal
from twisted.cred.checkers import FilePasswordDB
from twisted.internet import reactor

import os

# Sources
# - http://twistedmatrix.com/trac/attachment/ticket/1579/ftp_server_example.py
# - http://stackoverflow.com/questions/9790121/twisted-simple-file-completed-event-for-ftp-server


class MyFTP (FTP):
    def ftp_PASS(self, *args, **kwargs):
        # Get username before ftp_PASS deletes it
        username = self._user
        d = super(MyFTP, self).ftp_PASS(*args, **kwargs)

        # Pass username to getUsername callback
        d.addCallback(self.getUsername, username=username)
        return d

    def getUsername(self, result, username, *args, **kwargs):
        # Do something with username here
        self._username = username
        return result

    def ftp_STOR(self, path):
        d = super(MyFTP, self).ftp_STOR(path)
        d.addCallback(self.handleUpload, path=path)
        return d

    def handleUpload(self, result, path, *args, **kwargs):
        full_path = os.path.join(
            self.portal.realm.userHome.path,
            self._username,
            path
        )
        print(full_path)
        # Do something with file
        return result


p = Portal(
    FTPRealm(anonymousRoot='./', userHome='./dir'),
    (
        FilePasswordDB("pass.dat"),
    )
)

f = FTPFactory(p)
f.protocol = MyFTP

reactor.listenTCP(21, f)
reactor.run()