[Node.js] connection.session.store cannot read property of undefined

Posted by lee jones on Aug 11, 2014 in JavaScript

I recently ran into a problem whereby when attempting to use session-mongoose for session storage via MongoDB in a Node.js application, I was being hit with the error: connection.session.store cannot read property of undefined 1 connection.session.store cannot read property of undefined After Googling this with Bing and some other search engine jiggery-pokery I came up blank. Lots of references from a few years back which were down to a number of factors, but nothing relevant to my particular error. Looking at my code: var MongoSessionStore = require('session-mongoose')(session); var sessionStore = new MongoSessionStore({ url: credentials.mongo.development.connectionString }); app.use(require('express-session')({ store: sessionStore })); 12345 var MongoSessionStore = require('session-mongoose')(session); var sessionStore = new MongoSessionStore({ url: credentials.mongo.development.connectionString }); app.use(require('express-session')({ store: sessionStore })); And looking at the Github page for session mongoose there was nothing obviously wrong with what I was doing. Thus I started poking around in the node_modules folder to try and find out what is going on. It turns out that as Express and Connect have been largely decoupled, the Session middleware I no longer party of the connect object. However, session-mongoose hasn’t been updated to reflect this and thus it was still referencing connect.session.store. The Session object is no longer a property on the connect middleware, so the simple fix was to change the passed in parameter to session-mongoose function to connect.Store (/node_modules/session-mongoose/index.js:266). As is often the case, Node.js is still a very immature technology and the rate of change if its components and add-ins continues to cause compatibility and dependency problems, despite the best efforts of NPM.  ...