def post(self, url, params=None):
        """Perform an authenticated POST against a MAAS endpoint.

        :param url: MAAS endpoint
        :param params: extra data sent with the HTTP request
        """
        return requests.post(
            url=self._generate_url(url),
            headers=self._oauth_headers(),
            data=params
 
    def _generate_url(self, extra=u''):
        parsed = urlparse(self._url)
        api = u'/MAAS/api/%s/' % self.API_VERSION

        base_url = u'{protocol}://{netloc}'.format(protocol=self.PROTOCOL,
                                                   netloc=parsed.netloc)
        api_url = urljoin(base_url, api)
        return urljoin(api_url, extra)

    def _oauth_headers(self, additional_headers=None):
        """Return OAuth attributes for protected resources.

        :returns: headers to be used in http requests
        """
        consumer_key, key, secret = self.api_key.split(u':')
        resource_tok_string = u'oauth_token_secret=%s&oauth_token=%s' % (
            secret, key)
        resource_token = oauth.OAuthToken.from_string(resource_tok_string)
        consumer_token = oauth.OAuthConsumer(consumer_key, u'')

        oauth_request = oauth.OAuthRequest.from_consumer_and_token(
            consumer_token, token=resource_token,
            http_url=self._generate_url(),
            parameters={u'oauth_nonce': uuid.uuid4().hex})
        oauth_request.sign_request(
            oauth.OAuthSignatureMethod_PLAINTEXT(), consumer_token,
            resource_token)
        headers = oauth_request.to_header()
        if additional_headers:
            for key in additional_headers:
                headers[key] = additional_headers[key]
        return headers