Extract pem files from traefiks acme.json

traefik-extractor.py

import sys
import os
import errno
import json
from base64 import b64decode

def extract(file, output, challenge):
    # Read JSON file
    data = json.loads(open(file).read())

    certs = data[challenge]['Certificates']

    print('Certificate storage contains ' + str(len(certs)) + ' certificates')

    # Loop over all certificates
    for c in certs:
        name = c['domain']['main']
        privatekey = c['key']
        fullchain = c['certificate']

        # Decode private key, certificate and chain
        privatekey = b64decode(privatekey).decode('utf-8')
        fullchain = b64decode(fullchain).decode('utf-8')
        start = fullchain.find('-----BEGIN CERTIFICATE-----', 1)
        cert = fullchain[0:start]
        chain = fullchain[start:]

        # Create domain directory if it doesn't exist
        directory = output + '/' + name + '/'
        try:
            os.makedirs(directory)
        except OSError as error:
            if error.errno != errno.EEXIST:
                raise

        # Write private key, certificate and chain to file
        with open(directory + 'privkey.pem', 'w') as f:
            f.write(privatekey)

        with open(directory + 'cert.pem', 'w') as f:
            f.write(cert)

        with open(directory + 'chain.pem', 'w') as f:
            f.write(chain)

        with open(directory + 'fullchain.pem', 'w') as f:
            f.write(fullchain)

if __name__ == "__main__":
    extract(sys.argv[1], sys.argv[2], sys.argv[3])