Query for models with embedded discriminator is not working

[pwiebe]

Prerequisites

• I have written a descriptive issue title
• I have searched existing issues to ensure the bug has not already been reported

Mongoose version

6.8.3

Node.js version

18.12.0

MongoDB server version

4.4

Typescript version (if applicable)

No response

Description

When querying fields in a sub-model that is an embedded discriminator, no filtering is done. I.e. If the ids property is an array of a sub-model that has a discriminator, then all fields are returned, not the one filtered on.

Given the model in the repro steps, the command Testr.find({'ids.email.address': 'test@example.com'}) returns all items in the DB, not the filtered ones.

This was working in 5.13.15. Notice that running the same query directly on the MongoDB connection produces the desired result.

Steps to Reproduce

1. Create the following model:

const identity = new Schema({ primary: { type: Boolean, default: false } }, { discriminatorKey: 'kind' })

const EmailSchema = new Schema({
    email: {
        address: String,
        verified: Boolean
    }
})

const schema = new Schema({
    name: {
      first: String,
      last: String,
    },
    ids: [identity],
})
  
schema.path('ids').discriminator('emailIdentity', EmailSchema)
const Testr = mongoose.model('testr', schema)

2. Insert the following data:

 await Testr.create({
        name: { first: 'Frank', last: 'Instein'},
        ids: [{
            email: {address: 'test@example.com', verified: false},
            kind: 'emailIdentity'
        }],
    });

    await Testr.create({
        name: { first: 'Jane', last: 'Doe'},
        ids: [{
            email: {address: 'test1@example.com', verified: false},
            kind: 'emailIdentity'
        }],
    });

3. Run the following code:

    const t = await Testr.find({'ids.email.address': 'test@example.com'})
    const collection = Testr.$__collection;
    const t1 = await collection.find({'ids.email.address': 'test@example.com'}).toArray()

The expectation is that t and t1 have the same value.

Expected Behavior

Querying on an embedded discriminator sub-model should filter appropriately.

[IslandRhythms]

const mongoose = require('mongoose');

const { Schema } = mongoose;

const identity = new Schema({ primary: { type: Boolean, default: false } }, { discriminatorKey: 'kind' })

const EmailSchema = new Schema({
    email: {
        address: String,
        verified: Boolean
    }
})

const schema = new Schema({
    name: {
      first: String,
      last: String,
    },
    ids: [identity],
})
  
schema.path('ids').discriminator('emailIdentity', EmailSchema)
const Testr = mongoose.model('testr', schema)


async function run() {
  await mongoose.connect('mongodb://localhost:27017');
  await mongoose.connection.dropDatabase();

  await Testr.create({
    name: { first: 'Frank', last: 'Instein'},
    ids: [{
        email: {address: 'test@example.com', verified: false},
        kind: 'emailIdentity'
    }],
});

await Testr.create({
    name: { first: 'Jane', last: 'Doe'},
    ids: [{
        email: {address: 'test1@example.com', verified: false},
        kind: 'emailIdentity'
    }],
});

const t = await Testr.find({'ids.email.address': 'test@example.com'})
const collection = Testr.$__collection;
const t1 = await collection.find({'ids.email.address': 'test@example.com'}).toArray()
console.log('what is t', t, 'what is t1', t1);
}

run();

[vkarpov15]

This is an issue with strictQuery, run the following when your server starts to get the 5.x behavior:

mongoose.set('strictQuery', false);

We're changing strictQuery to false by default in 7.0 with #11861. Sorry for the trouble!