How to use the gssapi.names function in gssapi

def test_all_defaults(self):
        context = krbContext(using_keytab=True,
                             principal='HTTP/hostname@EXAMPLE.COM')

        self.assertTrue(context._cleaned_options['using_keytab'])
        expected_princ = gssapi.names.Name(
            'HTTP/hostname@EXAMPLE.COM',
            gssapi.names.NameType.kerberos_principal)
        self.assertEqual(expected_princ, context._cleaned_options['principal'])
        self.assertEqual(kctx.DEFAULT_CCACHE,
                         context._cleaned_options['ccache'])
        self.assertEqual(kctx.DEFAULT_KEYTAB,
                         context._cleaned_options['keytab'])

def setUp(self):
        self.principal = 'cqi'
        self.princ_name = gssapi.names.Name(self.principal,
                                            gssapi.names.NameType.user)

def test_specify_principal(self):
        context = krbContext(principal='cqi')
        expected_princ = gssapi.names.Name('cqi', gssapi.names.NameType.user)
        self.assertEqual(expected_princ,
                         context._cleaned_options['principal'])

if not req.auth:
                if optional:
                    req.context["user"] = None
                    return func(resource, req, resp, *args, **kwargs)

                logger.debug("No Kerberos ticket offered while attempting to access %s from %s",
                    req.env["PATH_INFO"], req.context.get("remote_addr"))
                raise falcon.HTTPUnauthorized("Unauthorized",
                    "No Kerberos ticket offered, are you sure you've logged in with domain user account?",
                    ["Negotiate"])

            os.environ["KRB5_KTNAME"] = config.KERBEROS_KEYTAB

            server_creds = gssapi.creds.Credentials(
                usage='accept',
                name=gssapi.names.Name('HTTP/%s'% const.FQDN))

            context = gssapi.sec_contexts.SecurityContext(creds=server_creds)

            if not req.auth.startswith("Negotiate "):
                raise falcon.HTTPBadRequest("Bad request", "Bad header: %s" % req.auth)

            token = ''.join(req.auth.split()[1:])

            try:
                context.step(b64decode(token))
            except binascii.Error: # base64 errors
                raise falcon.HTTPBadRequest("Bad request", "Malformed token")
            except gssapi.raw.exceptions.BadMechanismError:
                raise falcon.HTTPBadRequest("Bad request", "Unsupported authentication mechanism (NTLM?) was offered. Please make sure you've logged into the computer with domain user account. The web interface should not prompt for username or password.")

            try:

logger.debug("No credentials offered while attempting to access %s from %s",
                        req.env["PATH_INFO"], req.context.get("remote_addr"))
                    raise falcon.HTTPUnauthorized("Unauthorized", "Please authenticate", ("Basic",))

            if kerberized:
                if not req.auth.startswith("Negotiate "):
                    raise falcon.HTTPUnauthorized("Unauthorized",
                        "Bad header, expected Negotiate",
                        ["Negotiate"])

                os.environ["KRB5_KTNAME"] = config.KERBEROS_KEYTAB

                try:
                    server_creds = gssapi.creds.Credentials(
                        usage='accept',
                        name=gssapi.names.Name('HTTP/%s'% const.FQDN))
                except gssapi.raw.exceptions.BadNameError:
                    logger.error("Failed initialize HTTP service principal, possibly bad permissions for %s or /etc/krb5.conf" %
                        config.KERBEROS_KEYTAB)
                    raise

                context = gssapi.sec_contexts.SecurityContext(creds=server_creds)

                token = ''.join(req.auth.split()[1:])

                try:
                    context.step(b64decode(token))
                except binascii.Error: # base64 errors
                    raise falcon.HTTPBadRequest("Bad request", "Malformed token")
                except gssapi.raw.exceptions.BadMechanismError:
                    raise falcon.HTTPBadRequest("Bad request", "Unsupported authentication mechanism (NTLM?) was offered. Please make sure you've logged into the computer with domain user account. The web interface should not prompt for username or password.")

import json
import logging
import os
import re
import socket
import unicodedata
from identidude import config
from datetime import datetime, date

logger = logging.getLogger(__name__)

# http://firstyear.id.au/blog/html/2015/11/26/python_gssapi_with_flask_and_s4u2proxy.html
os.environ["KRB5_KTNAME"] = "FILE:/etc/identidude/server.keytab"
server_creds = gssapi.creds.Credentials(
    usage='accept',
    name=gssapi.names.Name('HTTP/%s'% (socket.gethostname())))

def apidoc(cls):
    """
    Automagically document resource classes based on validate(), required(), etc decorators
    """
    @serialize
    def apidoc_on_options(resource, req, resp, *args, **kwargs):
        d = {}
        for key in dir(resource):
            if key == "on_options": continue
            if re.match("on_\w+", key):
                func = getattr(resource, key)
                d[key[3:]] = getattr(func, "_apidoc", None)
                d[key[3:]]["description"] = (getattr(func, "__doc__") or u"").strip()

        return d

:param str keytab_file: refer to ``krbContext.__init__``.
        :param str ccache_file: refer to ``krbContext.__init__``.
        :param str password: refer to ``krbContext.__init__``.

        :return: a mapping containing cleaned names and values, which are used
            internally.
        :rtype: dict
        :raises ValueError: principal is missing or given keytab file does not
            exist, when initialize from a keytab.
        """
        cleaned = {}

        if using_keytab:
            if principal is None:
                raise ValueError('Principal is required when using key table.')
            princ_name = gssapi.names.Name(
                principal, gssapi.names.NameType.kerberos_principal)

            if keytab_file is None:
                cleaned['keytab'] = DEFAULT_KEYTAB
            elif not os.path.exists(keytab_file):
                raise ValueError(f'Keytab file {keytab_file} does not exist.')
            else:
                cleaned['keytab'] = keytab_file
        else:
            if principal is None:
                principal = get_login()
            princ_name = gssapi.names.Name(principal,
                                           gssapi.names.NameType.user)

        cleaned['using_keytab'] = using_keytab
        cleaned['principal'] = princ_name

if using_keytab:
            if principal is None:
                raise ValueError('Principal is required when using key table.')
            princ_name = gssapi.names.Name(
                principal, gssapi.names.NameType.kerberos_principal)

            if keytab_file is None:
                cleaned['keytab'] = DEFAULT_KEYTAB
            elif not os.path.exists(keytab_file):
                raise ValueError(f'Keytab file {keytab_file} does not exist.')
            else:
                cleaned['keytab'] = keytab_file
        else:
            if principal is None:
                principal = get_login()
            princ_name = gssapi.names.Name(principal,
                                           gssapi.names.NameType.user)

        cleaned['using_keytab'] = using_keytab
        cleaned['principal'] = princ_name
        cleaned['ccache'] = ccache_file or DEFAULT_CCACHE
        cleaned['password'] = password

        return cleaned

if principal is None:
                raise ValueError('Principal is required when using key table.')
            princ_name = gssapi.names.Name(
                principal, gssapi.names.NameType.kerberos_principal)

            if keytab_file is None:
                cleaned['keytab'] = DEFAULT_KEYTAB
            elif not os.path.exists(keytab_file):
                raise ValueError(f'Keytab file {keytab_file} does not exist.')
            else:
                cleaned['keytab'] = keytab_file
        else:
            if principal is None:
                principal = get_login()
            princ_name = gssapi.names.Name(principal,
                                           gssapi.names.NameType.user)

        cleaned['using_keytab'] = using_keytab
        cleaned['principal'] = princ_name
        cleaned['ccache'] = ccache_file or DEFAULT_CCACHE
        cleaned['password'] = password

        return cleaned