new_contents: #
  # Licensed under the Apache License, Version 2.0 (the "License"); you may
  # not use this file except in compliance with the License. You may obtain
  # a copy of the License at
  #
  #      http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  # License for the specific language governing permissions and limitations
  # under the License.
  
  from oslo.config import cfg
  
  from senlin.common import wsgi
  
  ssl_middleware_opts = [
      cfg.StrOpt('secure_proxy_ssl_header',
                 default='X-Forwarded-Proto',
                 help="The HTTP Header that will be used to determine which "
                      "the original request protocol scheme was, even if it was "
                      "removed by an SSL terminator proxy.")
  ]
  cfg.CONF.register_opts(ssl_middleware_opts)
  
  
  class SSLMiddleware(wsgi.Middleware):
      """A middleware that replaces the request wsgi.url_scheme environment
      variable with the value of HTTP header configured in
      secure_proxy_ssl_header if exists in the incoming request.
      This is useful if the server is behind a SSL termination proxy.
      """
      def __init__(self, application):
          super(SSLMiddleware, self).__init__(application)
          self.secure_proxy_ssl_header = 'HTTP_{0}'.format(
              cfg.CONF.secure_proxy_ssl_header.upper().replace('-', '_'))
  
      def process_request(self, req):
          req.environ['wsgi.url_scheme'] = req.environ.get(
              self.secure_proxy_ssl_header, req.environ['wsgi.url_scheme'])
  
subject: Add ssl middleware for Senlin API