Missing DocumentDefinitions export member after removing deprecated @typings/mongoose in favour of built-in typings

[replete]

First of all, thanks for this tutorial, I've been using it to learn TypeScript and get back to development after a few years on development hiatus.

I've been working on this codebase, and today just started having a go at implementing Jest, during which I've encountered a few head-scratchers which probably weren't a problem before because the project was using @types/mongoose definitions, which were for version 5.11.97, mismatching version 6 of the mongoose package used in this project.

(@types/mongoose is now deprecated so this problem will turn up when you remove the package and rely on mongoose package's built-in definitions)

My first attempt to resolve was replacing DocumentDefinition with Document, which creates this error:

Any ideas?

P.S. How's the Jest integration coming on? I was trying to implement Jest with supertest

[replete]

It looks like DocumentDefinition was removed in Mongoose 6, reverting to 5.13.11 resolves the issue, but introduces various other required code warnings such as
(node:97087) DeprecationWarning: current URL string parser is deprecated, and will be removed in a future version. To use the new parser, pass option { useNewUrlParser: true } to MongoClient.connect. (node:97087) [MONGODB DRIVER] Warning: Current Server Discovery and Monitoring engine is deprecated, and will be removed in a future version. To use the new Server Discover and Monitoring engine, pass option { useUnifiedTopology: true } to the MongoClient constructor.

[replete]

My temporary fix attempt, example user.service.ts

-import { DocumentDefinition, FilterQuery } from 'mongoose'
+import { FilterQuery } from 'mongoose'
...
+// Temp fix for DocumentDefinition in 6x
+import { _AllowStringsForIds, LeanDocument } from 'mongoose'
+type DocumentDefinition<T> = _AllowStringsForIds<LeanDocument<T>>

I took this from version 5.13.11. DocumentDefinition was exported in index.d.ts but only used in test/typescript/schema.ts which might explain why it was removed, and isn't in any official documentation 🤷‍♂️

...fails in Jest though:

    src/controller/product.controller.ts:18:38 - error TS2345: Argument of type '{ user: any; title: string; description: string; price: number; image: string; }' is not assignable to parameter of type 'DocumentDefinition<Omit<ProductDocument, "createdAt" | "updatedAt">>'.
      Types of property 'price' are incompatible.
        Type 'number' is not assignable to type 'string | LeanDocument<any>'.

    18  const product = await createProduct({ ...body, user: userId })
                                            ~~~~~~~~~~~~~~~~~~~~~~~~~

I'm a little out of my depth here being new to TypeScript, Express and Mongoose 😅

[tomanagle]

The types used for the services are just mirroring what Mongoose expects. So if you command-click into the mongoose method, you can explore the interface and see what types it expects.

[replete]

Thanks for your response, and sharing this tutorial with us.

Any ideas why it doesn't like price: number?

How would you go about fixing this, make another interface?

Are you still working on a Jest integration tutorial? If so I guess you'll face this problem.

[tomanagle]

I created a video about how to fix this issue: https://youtu.be/5-1KuU-21uI

The testing video has also been out for a few days now: https://youtu.be/r5L1XRZaCR0

[replete]

Thanks so much for doing that, Tom! Legendary.