Project 702 ~ Sales Order XML Parse

One of the stages in the project is to create a module which provides the functionality of automatically generating a sales order based on the values from an XML file retrived from an FTP server. Before I create a module I am going to create a test-driven example using the standard library ftplib which provides an FTP client, containing the functions (nlist and retrbinary) that are necessary. I am going to iterate over the files in the FTP server using nlst, and then download the file with retrbinary.

class FTPI(object):
    def __init__(self, ftpconn=None):
        if not os.path.isdir('ftp-files'):
            os.mkdir('ftp-files')
        self.filespath = 'ftp-files'
        self.ftpconn = ftpconn

    # Downloads (all) files from the ftp server and saves them to 'ftp-files'
    def download_files(self):
        for i, f in enumerate(self.ftpconn.nlst()):
            fhandler = open('%s/%s' % (self.filespath, f), 'wb')
            print('Fetching %s: %s' % (i, f))
            self.ftpconn.retrbinary('RETR %s' % (f), fhandler.write)
            fhandler.close()

Now to write the unittest ~ first one that fails

import unittest
import ftpi
import ftplib

class ftpi_testcase(unittest.TestCase):
 
    def test_ftpi_download_files_successful(self):
        server = ftplib.FTP('REDACTED')
        server.login('MISPELT USERNAME', 'REDACTED')
        ftpconn = ftpi.FTPI(server)
        self.assertNotEqual(ftpconn.download_files(), Exception)

if __name__ == '__main__':
    unittest.main()

======================================================================
ERROR: test_ftpi_download_files_successful (__main__.ftpi_testcase)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "test.py", line 11, in test_ftpi_download_files_successful
    server.login('MISPELT USERNAME', 'REDACTED')
  File "/usr/lib/python3.7/ftplib.py", line 420, in login
    resp = self.sendcmd('PASS ' + passwd)
  File "/usr/lib/python3.7/ftplib.py", line 273, in sendcmd
    return self.getresp()
  File "/usr/lib/python3.7/ftplib.py", line 246, in getresp
    raise error_perm(resp)
ftplib.error_perm: 530 Invalid userid/password

----------------------------------------------------------------------
Ran 1 test in 0.157s

FAILED (errors=1)

One that passes ~

import unittest
import ftpi
import ftplib

class ftpi_testcase(unittest.TestCase):
 
    def test_ftpi_download_files_successful(self):
        server = ftplib.FTP('REDACTED')
        server.login('CORRECT USERNAME', 'REDACTED')
        ftpconn = ftpi.FTPI(server)
        self.assertNotEqual(ftpconn.download_files(), Exception)

if __name__ == '__main__':
    unittest.main()

----------------------------------------------------------------------
Ran 1 test in 11.231s

OK

Not entirely sure if that is how assertNotEqual is supposed to be used but seems to work.

For the refactor part I am going merge the functions with an Odoo module.