(CkPython) FTP Connect, Examine Server Certificate, and then Authenticate

Demonstrates how to connect to an FTP server, examine the server's SSL/TLS certificate, and then, if it meets the application's security requirements, proceed to authenticate.

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import sys
import chilkat

# This example assumes Chilkat Ftp2 to have been previously unlocked.
# See Unlock Ftp2 for sample code.

ftp = chilkat.CkFtp2()

ftp.put_Hostname("www.authtls-ftps-server.com")
ftp.put_Username("FTP_LOGIN")
ftp.put_Password("FTP_PASSWORD")
ftp.put_AuthTls(True)
ftp.put_Port(21)

# Connect to the FTP server using explicit TLS (AUTH TLS).
success = ftp.ConnectOnly()
if (success != True):
    print(ftp.lastErrorText())
    sys.exit()

# Get the FTP server's certificate.
# serverCert is a CkCert
serverCert = ftp.GetSslServerCert()
if (ftp.get_LastMethodSuccess() != True):
    print(ftp.lastErrorText())
    sys.exit()

# Now that we have the certificate, we can check it in any way we desire.
# (See the online reference documentation for the certificate object's methods
# and properties)...

# Assuming the certificate is OK, proceed to authenticate with the FTP server.
success = ftp.LoginAfterConnectOnly()
if (success != True):
    print(ftp.lastErrorText())
    sys.exit()

# 
# Proceed with uploading/download files, etc...
# 

ftp.Disconnect()
print("Success.")