Updates-Via header in OPTIONS

Comienza localizando el manejo de solicitudes para las respuestas OPTIONS y HEAD, y busca la generación del encabezado Updates-Via. Reproduce la discrepancia con los comandos curl del issue contra la versión afectada del servidor y, después, verifica que el comportamiento esperado del encabezado sea coherente para ambos métodos.

The Solid WebSocket API Specs say that Updates-Via header can be found in an OPTIONS request to the server.

I am not finding an Updates-Via header in OPTIONS for node solid server, though I do get one if I do an HTTP HEAD:

$ curl -k -i  -X OPTIONS https://localhost:8443/public/
HTTP/1.1 204 No Content
X-Powered-By: solid-server/5.1.2
Vary: Accept, Authorization, Origin, Access-Control-Request-Headers
Access-Control-Allow-Credentials: true
Access-Control-Allow-Methods: OPTIONS,HEAD,GET,PATCH,POST,PUT,DELETE
Access-Control-Max-Age: 1728000
Access-Control-Expose-Headers: Authorization, User, Location, Link, Vary, Last-Modified, ETag, Accept-Patch, Accept-Post, Updates-Via, Allow, WAC-Allow, Content-Length, WWW-Authenticate
Allow: COPY,GET,HEAD,POST,PATCH,PUT,DELETE
Link: <https://localhost:8443/public/.well-known/solid>; rel="service", <https://localhost:8443>; rel="http://openid.net/specs/connect/1.0/issuer", <.acl>; rel="acl", <.meta>; rel="describedBy", <http://www.w3.org/ns/ldp#Container>; rel="type", <http://www.w3.org/ns/ldp#BasicContainer>; rel="type"
Accept-Patch: application/sparql-update
Accept-Post: */*
ETag: W/"23-dYHCBqdZ5e1V1nWlG0I6iB9SOvk"
Date: Wed, 05 Jun 2019 20:57:22 GMT
Connection: keep-alive

vs

$ curl -k --head https://localhost:8443/public/
HTTP/1.1 200 OK
X-Powered-By: solid-server/5.1.2
Vary: Accept, Authorization, Origin
Access-Control-Allow-Credentials: true
Access-Control-Expose-Headers: Authorization, User, Location, Link, Vary, Last-Modified, ETag, Accept-Patch, Accept-Post, Updates-Via, Allow, WAC-Allow, Content-Length, WWW-Authenticate
Allow: OPTIONS, HEAD, GET, PATCH, POST, PUT, DELETE
Link: <.acl>; rel="acl", <.meta>; rel="describedBy", <http://www.w3.org/ns/ldp#Container>; rel="type", <http://www.w3.org/ns/ldp#BasicContainer>; rel="type"
MS-Author-Via: SPARQL
Updates-Via: wss://localhost:8443
Content-Type: application/octet-stream; charset=utf-8
Content-Length: 2
ETag: W/"2-nOO9QiTIwXgNtWtBJezz8kv3SLc"
Date: Wed, 05 Jun 2019 20:57:00 GMT
Connection: keep-alive

This is using v5.1.2