Sessions collection is too big

I installed connect-mongo a few days ago now to store my express-sessions in my DB. Today I checked my sessions collection and found out that there were more than 200,000 documents in there! I tried deleting my collection and waiting 60 seconds, and there were already 200 documents in there.

Why are documents being resaved even though I have resave set to false? It seems as if documents are being saved endlessly…

Here is my current configuration:

app.use(session({
    secret: config.secret,
    resave: false,
    saveUninitialized: false,
    unset: 'destroy',
    store: new MongoStore({
        mongooseConnection: mongoose.connection,
        touchAfter: 3600, //Restore once every hour
        autoRemove: 'interval',
        autoRemoveInterval: 60 //Remove after one hour
    })
}));

At most I would only have around 3 users using my app at the moment.

I contacted connect-mongo and they stated that it would have to be an issue with express-session.

[dougwilson]

@romeboards , you also need ton use saveUninitialized: false, not saveUninitialized: true in your code, otherwise everything that hits your server, event assets, will keep creating a new session. If you are using true, then what you are experiencing is expected…

[joewagner]

@zilions From your first post you mention that you’ve got 200 documents after 60 seconds. Thats about 3 requests a second. That seems like quite a few for only 3 users. Do you log all requests? If you are getting that many requests, then somewhere in your code you are probably touching the session for each request even though you aren’t intending to use it. Based on previous issues I’ve seen, this is potentially happening in the jwt script you mention. But, I have no way to know that without grepping around your code. If you aren’t getting 3 requests/second, then something other than express-session is likely the culprit.
Either way, I wouldn’t think the indexes you have set on the collection have anything to do with the issue.