How to solve the problem with deploying to Travis-CI via FTP [TimeoutError: Connection timed out]?

Question

Python

With Travis-CI, I want to implement the following scenario:

• Running Tests
  
• Building the application in production view
  
• Server Deployment
  

There are no problems with the first and second points.
-------
Content of .travis.yml :

language: python
branches:
  only:
    - project/feature/CI&CD
python:
    - "3.7"
env:
    - DJANGO_VERSION=2.2.6
install:
    - pip install -q Django==$DJANGO_VERSION
    - sh install.sh
script: sh test.sh
after_success: 
    - sh build.sh
    - python deploy.py

-------
About the third in more detail:

• Deployment follows the principle of delivering files to an FTP server
  
• FTP Server configured on Windows Server 2012 via IIS
  
• The FTP client is the Python library 'ftplib'
  

-------
When Travis-CI runs the following script (simplified version):

import os
import ftplib

ftp = ftplib.FTP()
print(ftp.connect(HOST, PORT))
print(ftp.login(os.environ['FTP_USER'], os.environ['FTP_PASSWORD']))

if 'mainService-test' not in ftp.nlst():
    ftp.mkd('mainService-test')

Crashes with an error:

220 Microsoft FTP Service
230 User logged in.
Traceback (most recent call last):
  File "deploy.py", line 151, in <module>
    if 'mainService-test' not in ftp.nlst():
  File "/opt/python/3.7.1/lib/python3.7/ftplib.py", line 559, in nlst
    self.retrlines(cmd, files.append)
  File "/opt/python/3.7.1/lib/python3.7/ftplib.py", line 468, in retrlines
    with self.transfercmd(cmd) as conn, \
  File "/opt/python/3.7.1/lib/python3.7/ftplib.py", line 399, in transfercmd
    return self.ntransfercmd(cmd, rest)[0]
  File "/opt/python/3.7.1/lib/python3.7/ftplib.py", line 361, in ntransfercmd
    source_address=self.source_address)
  File "/opt/python/3.7.1/lib/python3.7/socket.py", line 727, in create_connection
    raise err
  File "/opt/python/3.7.1/lib/python3.7/socket.py", line 716, in create_connection
    sock.connect(sa)
TimeoutError: [Errno 110] Connection timed out

Those. there are no connection problems. The error occurs only on commands that require any data from the server.
When I run the same script on my machine, everything works!
-------
I would be grateful for any help provided!

Answer 1

When I run the same script on my machine, everything works!

Maybe your ftp server is only open to the internal network?

Answer 2

Those. there are no connection problems. The error occurs only on commands that require any data from the server.
When I run the same script on my machine, everything works!

it is necessary to rewrite in network terms
and, you see, you yourself will answer