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JavaScript User Authentication With Express and Mongo Improving the App with Custom Middleware Using MongoDB as a Session Store

matt thurmond
matt thurmond
8,743 Points
Posted by matt thurmond
matt thurmond
8,743 Points

connect-mongo error: "Class constructor MongoStore cannot be invoked without 'new'"

This isn't a question, just a solution to the broken code in the "Using MongoDB as a Session Store" video.

I believe the code in the video is broken due to a new release of the connect-mongo package (v4.x).

My console error was: "Class constructor MongoStore cannot be invoked without 'new'"

To fix it, I updated the code to the following: 

// require connect-mongo in app.js

const MongoStore = require('connect-mongo'); 

// manage user sessions in app.js

app.use(session({
  secret: 'treehouse loves you', 
  resave: true, 
  saveUninitialized: false, 
  store: MongoStore.create({
    mongoUrl: 'mongodb://localhost:27017/bookworm'
  })
}));

See here for more documentation of the latest connect-mongo release: https://github.com/jdesboeufs/connect-mongo

1 Answer

Leonardo Cavalcanti
Leonardo Cavalcanti
5,308 Points
Leonardo Cavalcanti
Leonardo Cavalcanti
5,308 Points

I had the same problem. Congrats for fixing it!