(Ruby) Encrypt Already Existing Zip

To encrypt an already existing non-encrypted .zip, the application must open the .zip, set the encryption related properties, and then re-write.

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

require 'chilkat'

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

zip = Chilkat::CkZip.new()

# Open an unencrypted .zip
success = zip.OpenZip("qa_data/zips/test.zip")
if (success != true)
    print zip.lastErrorText() + "\n";
    exit
end

# Unzip to a temp directory.
numFilesUnzipped = zip.Unzip("qa_output/tmp")
if (numFilesUnzipped < 0)
    print zip.lastErrorText() + "\n";
    exit
end

# Clear the zip object.
zip.NewZip("qa_output/aesTest.zip")

# Indicate that 128-bit AES encryption is to be used when writing the .zip
zip.put_Encryption(4)
zip.put_EncryptKeyLength(128)

# Set the password.
zip.put_EncryptPassword("secret")

# Append the files.
zip.put_AppendFromDir("qa_output/tmp")
success = zip.AppendFiles("*.*",true)
if (success != true)
    print zip.lastErrorText() + "\n";
    exit
end

# Write the .zip and close it.
success = zip.WriteZipAndClose()
if (success != true)
    print zip.lastErrorText() + "\n";
    exit
end

print "Success." + "\n";