Key Names with Periods

[vkarpov15]

Discussed in #13528

^{Originally posted by ccravens June 19, 2023}
I know it's not supported to have key names with periods in them (I'm sure that's a whole other discussion). But what I'm trying to do is understand why this schema definition results in this:

/*** Document save ******/
        const testModel = await new TestModel({
          metadata: {
            labels: { 'my.label.com': 'true' },
          },
        }).save();

This schema results in this:

const TestModelSchema = new mongoose.Schema({
  metadata: new Schema(
    {
      labels: Schema.Types.Mixed,
    },
    { _id: false }
  ),
});

> db.tests.find()
[
  {
    _id: ObjectId("6490a03b52d559b83ceb3ce2"),
    metadata: { labels: { 'my.label.com': 'true' } },
    __v: 0
  }
]
]

Notice the dots in the key name my.label.com

But schema results in this:

const TestModelSchema = new mongoose.Schema({
  metadata: {
      labels: Schema.Types.Mixed,
    },
});

> db.tests.find()
[
  {
    _id: ObjectId("6490a12452f4cca566b68d6d"),
    metadata: {
      labels: { my: { label: { com: 'true' } } }
    },
    __v: 0
  }
]
```</div>