(Ruby) Export Digital Certificate's Public Key

The ExportPublicKey method can be called to get a certificate's public key. It can then be saved to any of a number of formats: (1) OpenSSL DER, (2) OpenSSL PEM, (3) RSA DER, (4) XML.

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

require 'chilkat'

cert = Chilkat::CkCert.new()

# LoadFromFile will load virtually any certificate format file.
# It will auto-recognize the format and load appropiately.
success = cert.LoadFromFile("/Users/chilkat/testData/cer/chilkat.cer")
if (success != true)
    print cert.lastErrorText() + "\n";
    exit
end

# Get the public key:

# pubkey is a CkPublicKey
pubkey = cert.ExportPublicKey()
if (cert.get_LastMethodSuccess() == false)
    print cert.lastErrorText() + "\n";
    exit
end

# Save to various formats:
success = pubkey.SaveDerFile(false,"/Users/chilkat/testData/pubkeys/chilkat_pkcs8.der")
if (success != true)
    print pubkey.lastErrorText() + "\n";

    exit
end

success = pubkey.SavePemFile(false,"/Users/chilkat/testData/pubkeys/chilkat.pem")
if (success != true)
    print pubkey.lastErrorText() + "\n";

    exit
end

success = pubkey.SaveDerFile(true,"/Users/chilkat/testData/pubkeys/chilkat_pkcs1.der")
if (success != true)
    print pubkey.lastErrorText() + "\n";

    exit
end

success = pubkey.SaveXmlFile("/Users/chilkat/testData/pubkeys/chilkat.xml")
if (success != true)
    print pubkey.lastErrorText() + "\n";

    exit
end

print "Public key exported to all file formats." + "\n";