(Chilkat2-Python) 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.

Chilkat2 Python Downloads install with pip pip3 install chilkat2 or download... Python Module for Windows, Linux, Alpine Linux, MacOS, Solaris

import sys
import chilkat2

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

zip = chilkat2.Zip()

# Open an unencrypted .zip
success = zip.OpenZip("qa_data/zips/test.zip")
if (success != True):
    print(zip.LastErrorText)
    sys.exit()

# Unzip to a temp directory.
numFilesUnzipped = zip.Unzip("qa_output/tmp")
if (numFilesUnzipped < 0):
    print(zip.LastErrorText)
    sys.exit()

# 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.Encryption = 4
zip.EncryptKeyLength = 128

# Set the password.
zip.EncryptPassword = "secret"

# Append the files.
zip.AppendFromDir = "qa_output/tmp"
success = zip.AppendFiles("*.*",True)
if (success != True):
    print(zip.LastErrorText)
    sys.exit()

# Write the .zip and close it.
success = zip.WriteZipAndClose()
if (success != True):
    print(zip.LastErrorText)
    sys.exit()

print("Success.")