[help] InferSchemaType, accessing _id field

Prerequisites

• I have written a descriptive issue title

Mongoose version

6.4.0

Node.js version

18.3

MongoDB version

Unsure

Operating system

Linux

Operating system version (i.e. 20.04, 11.3, 10)

arch-5.18.5 something

Issue

Using InferSchemaType to create the schema interface type, how do I access the _id field? If I put it in the schema definition, I have to also set it explicitly when inserting new documents. If I don’t put it there, InferSchemaType does not include it in the interface.

What do I do? I’d like to know the same for .save() and so on. Am I supposed to do a type union?

Code:

import { Document, InferSchemaType, Schema } from "mongoose"

const mySchema = new Schema({
  foo: { type: String, required: true }
})

type MySchemaType_Problematic = InferSchemaType<typeof mySchema>
// MySchemaType_Problematic is missing the _id field along with the save() method etc.

// Workaround:
type MySchemaType_Workaround = InferSchemaType<typeof mySchema> & Document
// MySchemaType_Workaround can now be used properly, with _id and save() etc.

[vkarpov15]

@philiparvidsson can you please provide some code samples? That would be helpful for me to understand what you’re trying to do.

[vkarpov15]

From OP, I’d recommend doing:

type MySchemaType_Workaround = HydratedDocument<InferSchemaType<typeof mySchema>>

For “TL;DR: mongoose.Schema.Types.ObjectId should be inferred to mongoose.Types.ObjectId for fields”, this was fixed in 6.4.2 with #12007.

Those two issues are fixed, and there aren’t enough code samples for this to be actionable. So I’m going to close this. Please re-open with a complete code sample that we can run to demonstrate the issue you’re seeing, if you’re still having issues.