I have an exercise and it is now good and running. The algo of this exercise is to download files from FTP server zip it and upload it again in the upload folder in the FTP server again. BTW this is my code:
import os
import zipfile
import ConfigParser
import ftputil
import shutil
import tempfile
import time
def download_files():
# Alvin: Think of a better variable name
file_list = ftp.listdir(downloads)
for filename in file_list:
# Alvin should be ftp.path.join
source = os.path.join(downloads, filename)
target = os.path.join(temp_path, filename)
ftp.download(source, target)
def zipping_files():
dirlist = os.listdir(temp_path)
global filepath
filepath = os.path.join(temp_path, 'part2b.zip')
# Alvin: find better name for zip_name
global zip_name
zip_name = zipfile.ZipFile(filepath, 'w')
# Alvin: try not to use built-in names as variable names
for list in dirlist:
# Alvin: file_path, absolute_path
get_file = os.path.join(temp_path, list)
zip_name.write(get_file, 'part2b\\' + list)
def upload_files():
ftp.upload(filepath, uploads + '/part2b.zip')
def main():
# Alvin: Do not use globals.
# Alvin: remove useless and above all misleading comments
global temp_path
temp_path = tempfile.mkdtemp()
config = ConfigParser.ConfigParser()
config.readfp(open('config.ini'))
server = config.get('main', 'Server')
username = config.get('main', 'Username')
password = config.get('main', 'Password')
global uploads
uploads = config.get('main', 'Upload folder')
global downloads
downloads = config.get('main', 'Download folder')
#connect to ftp
global ftp
# Alvin: open ftp connection when you only need it.
ftp = ftputil.FTPHost(server, username, password)
try:
download_files()
zipping_files()
upload_files()
finally:
ftp.close()
zip_name.close()
shutil.rmtree(temp_path, 'true')
print "Successfully transferred files."
print ""
print "This will close in 5 seconds. . . . ."
time.sleep(5)
if __name__ == '__main__':
main()
Alright, the naming conventions leave that to me. But I want to ask for an example of how can I recode it without using all of my global variables? Thanks for your help!
You should definitly give parameters to your methods.
Here is how you can proceed:
One of the very best point of not using globals and having one function/one method is that it will be very easy to test/debug when something goes wrong.
Example:
your download_files()
requires downloads
and temp_path
, make them arguments, not globals