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CkPython

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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CkPython
import sys
import chilkat

success = False

# 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 = chilkat.CkMailMan()

# Set the SMTP server.
mailman.put_SmtpHost("smtp.mymailserver.com")

# Create a new email object
email = chilkat.CkEmail()

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

# Indicate that the email should be sent signed.
email.put_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 = chilkat.CkCertStore()
# 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()

# Find the certificate for the email address:
jsonE = chilkat.CkJsonObject()
jsonE.UpdateString("email","admin@chilkatsoft.com")

cert = chilkat.CkCert()
success = certStore.FindCert(jsonE,cert)
if (success == 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 = chilkat.CkCert()
# 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.put_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!")