(Ruby) DKIM Signature using Windows Current User Certificate Store

This is a Windows-specific example to load a certificate from the Current User (registry-based) certificate store, and then use the certificate's associated private key for a DKIM signature.

Chilkat Ruby Downloads install from rubygems.org gem install chilkat or download... Ruby Library for Windows, MacOS, Linux, Alpine Linux

require 'chilkat'

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

cert = Chilkat::CkCert.new()

# The LoadByCommonName method searches the Windows Local Machine and Current User 
# registry-based certificate stores for a certificate having the common name specified. 
# If found, the certificate is loaded and ready for use.
success = cert.LoadByCommonName("My Certificate ABC")
if (success != true)
    print cert.lastErrorText() + "\n";
    exit
end

# The certificate must have an associated private key installed, and it must be a
# private key that has been marked "exportable" when it was originally installed.
if (!cert.HasPrivateKey())
    print "This certificate does not have a private key available." + "\n";
    exit
end

# privKey is a CkPrivateKey
privKey = cert.ExportPrivateKey()
if (cert.get_LastMethodSuccess() == false)
    print cert.lastErrorText() + "\n";
    exit
end

dkim = Chilkat::CkDkim.new()

# Load the private key into the DKIM object:
success = dkim.LoadDkimPk(privKey.getPkcs8Pem(),"")
if (success != true)
    print dkim.lastErrorText() + "\n";
    exit
end

# The private key has been loaded into the DKIM object.  See the other DKIM
# examples for guidance on how to create a DKIM signature...