Python3 http.server supporting basic HTTP Auth (username/password)

http_server_auth.py

# Extended python -m http.serve with --username and --password parameters for
# basic auth, based on https://gist.github.com/fxsjy/5465353
# Usage: python -m http_server_auth -u USERNAME -p PASSWORD -d .
from functools import partial
from http.server import SimpleHTTPRequestHandler, test
import base64
import os


class AuthHTTPRequestHandler(SimpleHTTPRequestHandler):
    """ Main class to present webpages and authentication. """

    def __init__(self, *args, **kwargs):
        username = kwargs.pop("username")
        password = kwargs.pop("password")
        self._auth = base64.b64encode(f"{username}:{password}".encode()).decode()
        super().__init__(*args)

    def do_HEAD(self):
        self.send_response(200)
        self.send_header("Content-type", "text/html")
        self.end_headers()

    def do_AUTHHEAD(self):
        self.send_response(401)
        self.send_header("WWW-Authenticate", 'Basic realm="Test"')
        self.send_header("Content-type", "text/html")
        self.end_headers()

    def do_GET(self):
        """ Present frontpage with user authentication. """
        if self.headers.get("Authorization") == None:
            self.do_AUTHHEAD()
            self.wfile.write(b"no auth header received")
        elif self.headers.get("Authorization") == "Basic " + self._auth:
            SimpleHTTPRequestHandler.do_GET(self)
        else:
            self.do_AUTHHEAD()
            self.wfile.write(self.headers.get("Authorization").encode())
            self.wfile.write(b"not authenticated")


if __name__ == "__main__":
    import argparse

    parser = argparse.ArgumentParser()
    parser.add_argument("--cgi", action="store_true", help="Run as CGI Server")
    parser.add_argument(
        "--bind",
        "-b",
        metavar="ADDRESS",
        default="127.0.0.1",
        help="Specify alternate bind address " "[default: all interfaces]",
    )
    parser.add_argument(
        "--directory",
        "-d",
        default=os.getcwd(),
        help="Specify alternative directory " "[default:current directory]",
    )
    parser.add_argument(
        "port",
        action="store",
        default=8000,
        type=int,
        nargs="?",
        help="Specify alternate port [default: 8000]",
    )
    parser.add_argument("--username", "-u", metavar="USERNAME")
    parser.add_argument("--password", "-p", metavar="PASSWORD")
    args = parser.parse_args()
    handler_class = partial(
        AuthHTTPRequestHandler,
        username=args.username,
        password=args.password,
        directory=args.directory,
    )
    test(HandlerClass=handler_class, port=args.port, bind=args.bind)

I think it's somewhat misleading to name the utility function do_AUTHHEAD. do_X methods are called by the SimpleHTTPServer directly, while do_AUTHHEAD is a utility function called from do_X. It made understanding the code later difficult for me, at least.