(Chilkat2-Python) Send Signed Email using PFX File (long version)

Demonstrates how to send a signed email using a digital certificate w/ private key stored in a PFX file.

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import sys
import chilkat2

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# The mailman object is used for sending and receiving email.
mailman = chilkat2.MailMan()

# Set the SMTP server.
mailman.SmtpHost = "smtp.mymailserver.com"

# Create a new email object
email = chilkat2.Email()

email.Subject = "This email is signed"
email.Body = "This is a digitally signed mail"
email.From = "Chilkat Admin <admin@chilkatsoft.com>"
success = email.AddTo("Chilkat Support","support@chilkatsoft.com")

# Indicate that the email should be sent signed.
email.SendSigned = True

# Load a PFX file into a certificate store object.
# Then locate the certificate matching the  sender's email address,
# and use it for signing.
# (a PFX file may contain more than one certificate.)
certStore = chilkat2.CertStore()
# The 1st argument is the path of the PFX file, the 2nd arg is the 
# PFX file's password:
success = certStore.LoadPfxFile("/pfx_files/chilkatsoft_secret.pfx","secret")
if (success != True):
    print(certStore.LastErrorText)
    sys.exit()

# cert is a CkCert
cert = certStore.FindCertBySubjectE("admin@chilkatsoft.com")
if (certStore.LastMethodSuccess == False):
    print(certStore.LastErrorText)
    sys.exit()

# Alternatively, if a PFX file is known to contain a single certificate,
# you may load it directly into a Chilkat certificate object.
# This snippet of source code shows how:
cert2 = chilkat2.Cert()
# The 1st argument is the filename, the 2nd arg is the 
# PFX file's password:
success = cert2.LoadPfxFile("/pfx_files/chilkatsoft_secret.pfx","secret")
if (success != True):
    print(cert2.LastErrorText)

    sys.exit()

# This example will use the cert from the certStore...
success = email.SetSigningCert(cert)

# Signed email can be sent in two different ways.  
# In a multipart/signed email, the signature is attached as a separate MIME part.
# In an opaque email (signedData) the content of the email is encapsulated within the signature
# and the email is sent as "application/pkcs7-mime". 
# Either should be fine, but some receiving systems might require one or the other..
mailman.OpaqueSigning = False

# Send a signed email.
success = mailman.SendEmail(email)
if (success != True):
    print(mailman.LastErrorText)
else:
    # The LastErrorText property provides information
    # even when successful.
    print(mailman.LastErrorText)
    print("Mail Sent!")