How to restrict additional properties in Mongoose with TypeScript and always return .toJSON property?

[gabrielgrs]

Hello!
Is there a way to enforce that only the properties defined in my Mongoose schema are allowed? I want to prevent any extra properties from being accepted or saved. What's the best approach to achieve this?

And is there a way to always return the object as ".toJSON"?

[vkarpov15]

1. strict: 'throw' option in your schema definition: https://mongoosejs.com/docs/guide.html#strict
2. Not exactly, closest equivalent would be using lean() for queries: https://mongoosejs.com/docs/tutorials/lean.html