return maintype == 'text' and encoding == None # not compressed

def connectFtp(cf):
print('connecting...')
connection = ftplib.FTP(cf.remotesite) # connect to FTP site
connection.login(cf.remoteuser, cf.remotepass) # log in as user/password
connection.cwd(cf.remotedir) # cd to directory to xfer
if cf.nonpassive: # force active mode FTP
connection.set_pasv(False) # most servers do passive
return connection

def cleanLocals(cf):
"""
try to delete all locals files first to remove garbage
"""
if cf.cleanall:
for localname in os.listdir(cf.localdir): # local dirlisting
try: # local file delete
print('deleting local', localname)
os.remove(os.path.join(cf.localdir, localname))
except:
print('cannot delete local', localname)

def downloadAll(cf, connection):
"""
download all files from remote site/dir per cf config
ftp nlst() gives files list, dir() gives full details
"""
remotefiles = connection.nlst() # nlst is remote listing
for remotename in remotefiles:
if remotename in ('.', '..'): continue
localpath = os.path.join(cf.localdir, remotename)
print('downloading', remotename, 'to', localpath, 'as', end=' ')
if isTextKind(remotename):

use text mode xfer

localfile = open(localpath, 'w', encoding=connection.encoding)
def callback(line): localfile.write(line + '\n')
connection.retrlines('RETR ' + remotename, callback)
else:

use binary mode xfer

localfile = open(localpath, 'wb')
connection.retrbinary('RETR ' + remotename, localfile.write)
localfile.close()
connection.quit()
print('Done:', len(remotefiles), 'files downloaded.')

if name == 'main':
cf = configTransfer()
conn = connectFtp(cf)
cleanLocals(cf) # don't delete if can't connect
downloadAll(cf, conn)

Compare this version with the original. This script, and every other in this section, runs
the same as the original flat download and upload programs. Although we haven’t

886 | Chapter 13: Client-Side Scripting