import re
import falcon
from sikre import settings
from sikre.utils.logs import logger
[docs]class BaseHeaders(object):
# Unused regular expression to check that origin is always a website.
# expression = re.compile("^(https?:\/\/)?([\da-z\.-]+)\.([a-z\.]{2,6})([\/\w \.-]*)*\/?$")
[docs] def process_request(self, req, res):
"""Process the request before entering in the API
Before we process anything in the API, we reset the Origin header to
match the address from the request.
Args:
Access-Control-Allow-Origin: Change the origin to the URL that made
the request.
Raises:
HTTP Error: An HTTP error in case the Origin header doesn't match
the predefined regular expression.
Return:
HTTP headers: A modified set of headers.
"""
origin_domain = req.get_header('Origin')
logger.debug("Origin domain is: {}, type: {}".format(origin_domain, type(origin_domain)))
origin_header = origin_domain if settings.CORS_ACTIVE and origin_domain else "*"
logger.debug("Origin header is: {}, type: {}".format(origin_header, type(origin_header)))
res.set_headers([
('Cache-Control', 'no-store, must-revalidate, no-cache, max-age=0'),
('Content-Type', 'application/json; charset=utf-8'),
('Access-Control-Allow-Credentials', 'true'),
('Access-Control-Allow-Origin', origin_header),
('Access-Control-Allow-Headers', 'Origin, X-Requested-With, Content-Type, Accept, x-auth-user, x-auth-password, Authorization'),
('Access-Control-Allow-Methods', 'GET, PUT, POST, OPTIONS, DELETE')
])
[docs] def process_response(self, req, res, resource):
"""Process the response before returning it to the client.
In the reutrning reponse we change some values to be able to overcome
the CORS protection and mask the origin server. The CORS interaction
is protected by a check agains a regular expression to make sure the
origin is a website-like URL.
Warning:
If you are really concerned about security, you can deactivate
the CORS allowance by turning CORS_ACTIVE to `False` in your settings
file. That will force the application to answer to the SITE_DOMAIN
domain.
Args:
Server (string): Changes the server name sent to the browser in the
response to avoid exposure of name and version of the same.
Access-Control-Allow-Origin (string): Change the origin name to
match the one that made the request. That way we can allow CORS
anywhere.
Raises:
HTTP Error: An HTTP error in case the Origin header doesn't match
the predefined regular expression.
Returns:
HTTP headers: A modified set of headers
"""
origin_domain = req.get_header('Origin')
logger.debug("Origin domain is: {}, type: {}".format(origin_domain, type(origin_domain)))
origin_header = origin_domain if settings.CORS_ACTIVE and origin_domain else "*"
logger.debug("Origin header is: {}, type: {}".format(origin_header, type(origin_header)))
res.set_headers([
('Cache-Control', 'no-store, must-revalidate, no-cache, max-age=0'),
('Content-Type', 'application/json; charset=utf-8'),
('Server', settings.SERVER_NAME),
('Access-Control-Allow-Credentials', 'true'),
('Access-Control-Allow-Origin', origin_header),
('Access-Control-Allow-Headers', 'Origin, X-Requested-With, Content-Type, Accept, x-auth-user, x-auth-password, Authorization'),
('Access-Control-Allow-Methods', 'GET, PUT, POST, OPTIONS, DELETE')
])