Simple way to allow all CORS / OPTIONS requests?

[ghost]

I'm wanting to open the door wide to all CORS requests to my application.

I can see there is an additional Falcon/CORS middleware project but I'm hoping there is some simpler way to just open the door wide with a few lines of code and no need to worry about understanding and implementing the middleware and the various options and fine tuning that it provides.

Any suggestions for how to do this?

[ghost]

Answering my own question:

import falcon
from falcon.http_status import HTTPStatus

class HandleCORS(object):
    def process_request(self, req, resp):
        resp.set_header('Access-Control-Allow-Origin', '*')
        resp.set_header('Access-Control-Allow-Methods', '*')
        resp.set_header('Access-Control-Allow-Headers', '*')
        resp.set_header('Access-Control-Max-Age', 1728000)  # 20 days
        if req.method == 'OPTIONS':
            raise HTTPStatus(falcon.HTTP_200, body='\n')

wsgi_app = api = falcon.API(middleware=[HandleCORS() ])

[vytas7]

It seems you have coined a solution that fits your needs 😈

Your question is otherwise actually answered in the FAQ [1], and the answer is really fairly similar to yours. Note the suggestion handles 'OPTIONS' in a slightly different way (by telling which methods are supported instead of saying "all methods"), but yours would do too.

1. https://falcon.readthedocs.io/en/stable/user/faq.html#how-do-i-implement-cors-with-falcon

[vytas7]

Also note that a simple to way to add unsophisticated permissive CORS is under consideration to be included in Falcon 2.0: #1194

[MockArch]

DeprecatedWarning: Call to deprecated function init(...). API class may be removed in a future release, use falcon.App instead.

use :

`class HandleCORS(object):
def process_request(self, req, resp):
resp.set_header('Access-Control-Allow-Origin', '')
resp.set_header('Access-Control-Allow-Methods', '')
resp.set_header('Access-Control-Allow-Headers', '*')
resp.set_header('Access-Control-Max-Age', 1728000) # 20 days
if req.method == 'OPTIONS':
raise HTTPStatus(falcon.HTTP_200, body='\n')

app = falcon.App(middleware=[HandleCORS() ])`

[vytas7]

Thanks for the tip, @MockArch 👍

Note though that as of Falcon 3.0+, the CORS functionality is now included in the framework.
The simplest way of adding a permissive CORS policy is now:

import falcon

# Enable a simple CORS policy for all responses
app = falcon.App(cors_enable=True)

(You can also address some more complex use cases by adding an instance of CORSMiddleware to your app.)