Authenticating Apollo Websocket subscription with nginx/lua

Question

Trying out Hasura with an Apollo client, and followed documentation for adding authTokens: https://www.apollographql.com/docs/react/data/subscriptions/

import { GraphQLWsLink } from '@apollo/client/link/subscriptions';
import { createClient } from 'graphql-ws';

const wsLink = new GraphQLWsLink(createClient({
  url:url,
  connectionParams: {
    authToken: user.authToken,
  },
}));

My url goes to a nginx reverse proxy setup, which looks like something like this:

location /ws {
    proxy_pass http://wsbackend;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "Upgrade";
    proxy_set_header Host $host;
}

At this point, I'm a little lost on how to have my JWT Token that exists in the first connection request get authenticated here? I have to somehow gain access to the connection request payload? My other regular http requests get authenticated with Authorization in the header through a LUA script(access_by_lua_file).