split-certs.py

#!/usr/bin/env python
'''
split-certs.py

Splits certificates
'''

from __future__ import print_function
from argparse import ArgumentParser
import os


def main():
    '''
    Splits PEM encoded certificates
    '''
    parser = ArgumentParser(description=main.__doc__)
    parser.add_argument('-i', '--input', default='-', help='File to read from, defaults to stdin')
    parser.add_argument('output', default='.', help='Output directory to write certificates to')
    args = parser.parse_args()

    if args.input == '-':
        file_content = sys.stdin.read()
    else:
        with open(args.input, 'r') as f:
            file_content = f.read()

    certs = []
    buf = []
    for line in file_content.split('\n'):
        if line == '-----BEGIN CERTIFICATE-----':
            buf = [line]
        elif line == '-----END CERTIFICATE-----':
            buf.append(line)
            buf.append('')
            certs.append('\n'.join(buf))
            buf = []
        else:
            buf.append(line)

    for i, cert in enumerate(certs):
        path = os.path.join(args.output, '{}.crt'.format(str(i)))
        with open(path, 'w') as f:
            f.write(cert)


    return 0

if __name__ == '__main__':
    import sys
    sys.exit(main())