Unable to get context for subscriptions

I have the following code:

const server = new ApolloServer({
    ........

    subscriptions: {
        onConnect: (connectionParams, webSocket, context) => {
            // check for headers
            let username = <username from connectionParams->headers>
            return { username }   // according to the documentation, returning here adds the parameter to context, can't seem to get this in subscription function
        },
    },

    context: ({ req, res }) => {
        if (req, req.headers){
            // non-subscription calls
            return <username from connectionParams->headers>
        }else{
            // we get here when we use subscription query
            // req and res are empty
            return;
        }
    },

    ........
)}

And then in the subscription resolver

........

    Subscription: {
        somethingChanged: {
            // Additional event labels can be passed to asyncIterator creation
            subscribe: withFilter(() => pubsub.asyncIterator('SOMETHING_CHANGED'), (payload, variables, context, info) => {
                console.log(payload, variables, context, info)
                return true
            }),
        },
    },
........

I cannot seem to send the username from onConnect to the context within withFilter. I am trying to achieve this because once I have the context (i.e. headers/auth), I want to compare it to the payload.

[deathg0d]

Solved by https://github.com/apollographql/apollo-server/issues/1597#issuecomment-423641175

[thilllon]

@judithkoh