SimpleAuthServer: A SimpleHTTPServer with authentication

SimpleAuthServer3.py

# Python3 compatible
import http.server
from http.server import SimpleHTTPRequestHandler
import sys
import base64

key = ""

class AuthHandler(SimpleHTTPRequestHandler):
    ''' Main class to present webpages and authentication. '''
    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):
        global key
        ''' Present frontpage with user authentication. '''
        auth = self.headers.get('Authorization')
        if auth == None:
            self.do_AUTHHEAD()
            self.wfile.write(b'no auth header received')
        elif auth == 'Basic '+ key.decode('utf8'):
            SimpleHTTPRequestHandler.do_GET(self)
        else:
            self.do_AUTHHEAD()
            self.wfile.write(bytes(auth, 'utf8'))
            self.wfile.write(b'not authenticated')

def test(HandlerClass = AuthHandler,
         ServerClass = http.server.HTTPServer):
    http.server.test(HandlerClass, ServerClass)


if __name__ == '__main__':
    if len(sys.argv)<3:
        print("usage SimpleAuthServer.py [port] [username:password]")
        sys.exit()
    key = base64.b64encode(bytes(sys.argv[2], 'utf8'))
    test()