CORS support needed

[fnoop]

2018-02-15 21:59:15,218 WARNING 403 GET /subscriptions (127.0.0.1) 0.58ms
2018-02-15 21:59:15,219 DEBUG Cross origin websockets not allowed

CORS is needed if our web GCS will support multiple endpoints, by definition any additional endpoint will be cross origin.

[fnoop]

Added method to GQLSubscriptionHandler to turn off cors checks:

    def check_origin(self, origin):
        self.CORS_ORIGINS = ['localhost', 'www.example.com']
        parsed_origin = urlparse(origin)
        # return parsed_origin.hostname in self.CORS_ORIGINS
        return True

It currently returns True which disables CORS checks regardless, but should check the hostname against CORS_ORIGINS which should be taken from the config file.
CORS checks can be disabled if we add auth to the websockets

[fnoop]

Websockets OK but query endpoint rejecting:

Failed to load http://www.maverick.one/maverick-api/graphql: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://dev.maverick.one' is therefore not allowed access. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.
vue-apollo.esm.js?ebd5:2671 Error sending the query 'stateMessage' TypeError: Failed to fetch

[SamuelDudley]

https://stackoverflow.com/questions/35254742/tornado-server-enable-cors-requests

[fnoop]

I've basically turned off origin checks for websockets and http requests - check the commits referenced, but this should probably stay open as a marker to investigate CORS and ramifications more closely.
I've added support for auth in the client which we should look into supporting at the api end, will raise a separate issue.

[fnoop]

Getting CORS errors in firefox - works fine in chrome:

[SamuelDudley]

Looks like an issue with chrome. As far as I can understand the preflight options call is made without the cert in Firefox but not chrome. Reading the above thread there may be a nginx setting that needs changing.

https://bugzilla.mozilla.org/show_bug.cgi?id=1019603

[SamuelDudley]

ssl_verify_client on -> ssl_verify_client optional

[fnoop]

These requests aren't going through nginx - they're direct to -api

[SamuelDudley]

These requests aren't going through nginx - they're direct to -api

Yep good call! After some more debugging in firefox the problem appears to be a certificate issue. I too had this problem initially with firefox however once the certificate was installed correctly all requests via https work as expected (linux + firefox). Note webrtc video does not work but that appears to be a browser compatibility issue rather than anything else.

[SamuelDudley]

In the screenshot you can see that the CORS requests are being made okay. You can also see the video is not playing. Possibly due to this error:

will raise a separate issue