#!/usr/bin/env python3
'''
example of connexion running behind a path-altering reverse-proxy

NOTE this demo is not secure by default!!
You'll want to make sure these headers are coming from your proxy, and not
directly from users on the web!

'''
import logging

import connexion


# adapted from http://flask.pocoo.org/snippets/35/
class ReverseProxied(object):
    '''Wrap the application in this middleware and configure the
    reverse proxy to add these headers, to let you quietly bind
    this to a URL other than / and to an HTTP scheme that is
    different than what is used locally.

    In nginx:

    location /proxied {
        proxy_pass http://192.168.0.1:5001;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Scheme $scheme;
        proxy_set_header X-Forwarded-Path /proxied;
    }

    :param app: the WSGI application
    :param script_name: override the default script name (path)
    :param scheme: override the default scheme
    :param server: override the default server
    '''

    def __init__(self, app, script_name=None, scheme=None, server=None):
        self.app = app
        self.script_name = script_name
        self.scheme = scheme
        self.server = server

    def __call__(self, environ, start_response):
        logging.warning(
            "this demo is not secure by default!! "
            "You'll want to make sure these headers are coming from your proxy, "
            "and not directly from users on the web!"
            )
        script_name = environ.get('HTTP_X_FORWARDED_PATH', '') or self.script_name
        if script_name:
            environ['SCRIPT_NAME'] = "/" + script_name.lstrip("/")
            path_info = environ['PATH_INFO']
            if path_info.startswith(script_name):
                environ['PATH_INFO_OLD'] = path_info
                environ['PATH_INFO'] = path_info[len(script_name):]
        scheme = environ.get('HTTP_X_SCHEME', '') or self.scheme
        if scheme:
            environ['wsgi.url_scheme'] = scheme
        server = environ.get('HTTP_X_FORWARDED_SERVER', '') or self.server
        if server:
            environ['HTTP_HOST'] = server
        return self.app(environ, start_response)


def hello():
    return "hello"


if __name__ == '__main__':
    app = connexion.FlaskApp(__name__)
    app.add_api('openapi.yaml')
    flask_app = app.app
    proxied = ReverseProxied(
        flask_app.wsgi_app,
        script_name='/reverse_proxied/'
    )
    flask_app.wsgi_app = proxied
    app.run(port=8080)