Useful or not, from you.
node-rate-limiter-flexible Cannot read property 'collection' of undefined with RateLimiterMongo

I'm implementing rate limit functionality with RateLimiterMongo and _initCollection function throws TypeError: Cannot read property 'collection' of undefined. Changing this.client.db to this.client from rows 80 and 81 will fix the issue.

This is with MongoDB version 3.4.10.

That's a useful answer
Without any help

@tero Which version of mongoose do you use?