How to catch error messages in ftplib?

[JL]

I have the following code;

try:
session = FTP(ftp_server_ip,ftp_user,ftp_password)
file = open(filename,'rb') # file to send
session.storbinary('STOR ' + filename, file) # send the file
except Exception, errObj:
print Exception
print errObj
file.close() # close file and FTP
session.quit()

I deliberately placed an invalid ip address for the ftp_server_ip to see whether error messages can be caught. However, no exception was thrown. Can someone more experienced point to me what did I do wrong?

Thank you.

 

[JL]

I repost the original code segment to make it more complete;

from ftplib import FTP
try:
session = FTP(ftp_server_ip,ftp_user,ftp_password)
file = open(filename,'rb') # file to send
session.storbinary('STOR ' + filename, file) # send the file
except Exception, errObj:
print Exception
print errObj
file.close() # close file and FTP
session.quit()

 

[Chris Angelico]

I have the following code;

try:
session = FTP(ftp_server_ip,ftp_user,ftp_password)
file = open(filename,'rb') # file to send
session.storbinary('STOR ' + filename, file) # send the file
except Exception, errObj:
print Exception
print errObj
file.close() # close file and FTP
session.quit()

I deliberately placed an invalid ip address for the ftp_server_ip to see whether error messages can be caught. However, no exception was thrown. Can someone more experienced point to me what did I do wrong?

My first suggestion would be to get rid of the try/except block - it's
not really helping you. Just let the exception be displayed. When I
try that, I get a variety of different errors, depending on what sort
of "invalid IP address" was used - if it's malformed
("192.168.1.2.3"), I get a DNS failure, if it's a computer that
doesn't exist but ought to be on my LAN ("192.168.0.2"), I get a
timeout, and if it's one that exists but doesn't have an FTP server
running ("192.168.0.3"), I get a connection refusal. Exactly what I'd
expect to see. Removing the try/except will show what's happening.

ChrisA