TypeScript: Document type not passed along with collection()

[SteffenLanger]

Do you want to request a feature or report a bug?
Bug 🐞

What is the current behavior?
This is a type definition issue.

Let's assume the documents in a collection have an _id of type string. When updating a document in that collection using a query for _id, TypeScript shows the error "TS2322: Type 'string' is not assignable to type 'Condition'."

If the current behavior is a bug, please provide the steps to reproduce.
Write this code:

import mongoose from 'mongoose';

await mongoose.connection.collection('teams').updateOne({_id : 'abc-ID'}, {
    $set : {
        'name' : 'New team name'
    }
});

Currently, MongoDB's types have a Document parameter while Mongoose's types do not:
MongoDB type (extracts)

export declare class Collection<TSchema extends Document = Document> {

updateOne(filter: Filter<TSchema>, update: UpdateFilter<TSchema> | Partial<TSchema>): Promise<UpdateResult>;

Mongoose type (extract)

interface Collection extends CollectionBase {

interface CollectionBase extends mongodb.Collection {

Mongoose uses MongoDB's type definition for updateOne. Since no parameter is passed to the Collection above, the default type "Document" is assumed and that requires an ObjectID.

My tsconfig.json:

{
    "compilerOptions": {
        "module": "ES2020",
        "esModuleInterop": true,
        "target": "ES2021",
        "noImplicitAny": false,
        "moduleResolution": "node",
        "sourceMap": true,
        "resolveJsonModule": true,
        "lib": [
            "dom",
            "ES2021"
        ]
    }
}

What is the expected behavior?
The type of the function mongoose.connection.collection should have a parameter Document that is passed to the underlying MongoDB type Collection. Example:

interface Collection<TSchema extends Document = Document> extends CollectionBase<TSchema> {

interface CollectionBase<TSchema extends Document = Document> extends mongodb.Collection<TSchema> {

Then, the _id would be recognized as a string from the Document definition type parameter TSchema. No error would be shown.

What are the versions of Node.js, Mongoose and MongoDB you are using? Note that "latest" is not a version.
Node.js: v16.13.1
Mongoose: 6.1.2
MongoDB: 4.4.10

[DavideViolante]

Not happening to me with the following code and same version.

...
const MyModel = model<IMyModel>('MyModel', myModelSchema);

await MyModel.updateOne({ _id: 'abc-ID'}, {
  $set: { name: 'New team name' }
});

Btw try to update to 6.1.3 or change your code to something like this:

await Teams.updateOne({ _id: 'abc-ID' }, { 'name': 'New team name' });
// where Teams is the model as MyModel above

more info https://mongoosejs.com/docs/typescript/schemas.html

[SteffenLanger]

True, but that solution completely avoids the wrongly defined types on the connection 😁 Another workaround would be this code (note the .db after connection which accesses the MongoDB connection object with a collection function that can be typed):

import mongoose from 'mongoose';
interface Team {
  _id: string;
  name: string;
}

await mongoose.connection.db.collection<Team>('teams').updateOne({_id : 'abc-ID'}, {
    $set : {
        'name' : 'New team name'
    }
});

This GitHub issue is not meant to get a working solution - I got that. It's a contribution to help fix the types.

The use case for the code posted above is data migrations. Models might have been updated to have default values or field validations that should not be used within the migration.

[DavideViolante]

I can reproduce with v6.1.3 and the error showed is:

(property) _id?: Condition<ObjectId>
Type 'string' is not assignable to type 'Condition<ObjectId>'.ts(2322)
mongodb.d.ts(5858, 5): The expected type comes from property '_id' which is declared here on type 'Filter<Document>'

it seems like the error is coming from mongodb, not mongoose types, if I'm not mistaken?

[SteffenLanger]

Yes, the error is caused by the MongoDB types - and it should be that way. The underlying issue lies within the Mongoose types, however. Mongoose uses MongoDB's types for updateOne() and other operations. MongoDB's types would work correctly if Mongoose passed its collection type to MongoDB's collection type.