cert_human_cli.py

#! /usr/bin/env python
# -*- coding: utf-8 -*-
"""Command line interface to request a URL and get the server cert or cert chain."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals

import argparse
import cert_human
import sys


def cli(argv):
    """Parse arguments.

    Args:
        argv (:obj:`list`): sys.argv or manual list of args to parse.

    Returns:
        (:obj:`argparse.Namespace`)

    """
    fmt = argparse.ArgumentDefaultsHelpFormatter
    parser = argparse.ArgumentParser(description=__doc__, formatter_class=fmt)
    parser.add_argument(
        "host",
        metavar="HOST",
        action="store",
        type=str,
        help="Host to get cert or cert chain from",
    )
    parser.add_argument(
        "--port",
        default=443,
        action="store",
        required=False,
        type=int,
        help="Port on host to connect to",
    )
    parser.add_argument(
        "--method",
        dest="method",
        action="store",
        default="requests",
        required=False,
        choices=["requests", "socket"],
        help="Use requests.get a SSL socket to get cert or cert chain.",
    )
    parser.add_argument(
        "--chain",
        dest="chain",
        action="store_true",
        default=False,
        required=False,
        help="Print/write the cert chain instead of the cert.",
    )
    parser.add_argument(
        "--print_mode",
        dest="print_mode",
        action="store",
        default="info",
        required=False,
        choices=["info", "key", "extensions", "all"],
        help="When no --write specified, print this type of information for the cert.",
    )
    parser.add_argument(
        "--write",
        dest="write",
        action="store",
        default="",
        required=False,
        help="File to write cert/cert chain to",
    )
    parser.add_argument(
        "--overwrite",
        dest="overwrite",
        action="store_true",
        default=False,
        required=False,
        help="When writing to --write and file exists, overwrite.",
    )
    parser.add_argument(
        "--verify",
        dest="verify",
        action="store",
        default="",
        required=False,
        help="PEM file to verify host, empty will disable verify, for --method requests.",
    )
    return parser.parse_args(argv)


def main(cli_args):
    """Process arguments and run the workflows.

    Args:
        cli_args (:obj:`argparse.Namespace`): Parsed args from sys.argv or list.

    """
    if cli_args.chain:
        store_cls = cert_human.CertChainStore
        store_target = "cert chain"
    else:
        store_cls = cert_human.CertStore
        store_target = "cert"

    if cli_args.method == "requests":
        verify = False if not cli_args.verify else cli_args.verify
        try:
            store_obj = store_cls.new_from_host_requests(
                host=cli_args.host, port=cli_args.port, verify=verify
            )
        except cert_human.requests.exceptions.SSLError as exc:
            exc = "\n  ".join([x.strip() for x in format(exc).split(":")])
            m = "SSL Validation Failed:\n  {exc}".format(exc=exc)
            print(m)
            store_obj = None
    elif cli_args.method == "socket":
        store_obj = store_cls.new_from_host_socket(
            host=cli_args.host, port=cli_args.port
        )

    if store_obj:
        if cli_args.write:
            store_obj.to_disk(path=cli_args.write, overwrite=cli_args.overwrite)
            m = "** Wrote {t} in pem format to: '{p}'"
            m = m.format(t=store_target, p=cli_args.write)
            print(m)
        else:
            print_map = {
                "info": "dump_str_info",
                "key": "dump_str_key",
                "all": "dump_str",
                "extensions": "dump_str_exts",
            }
            mode_out = getattr(store_obj, print_map[cli_args.print_mode])
            print(mode_out)


if __name__ == "__main__":
    cli_args = cli(argv=sys.argv[1:])
    main(cli_args)