_id and id in document are treated the same since 7.4.0

[salos1982]

Prerequisites

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

Mongoose version

7.4.0

Node.js version

18.x

MongoDB server version

7.0

Typescript version (if applicable)

5.0

Description

When I try to insert object that contains id field it is transformed to _id field and then is trying to insert.
Deleting id field before insert helps.

Steps to Reproduce

I have schema without id field. But when I try to insert new object with id field it is treated as string version of _id.
E.g. Schema

export class A {
name: string;
}

if I try to insert object

{
  id: "existing _id of another object"
  name: "A"
}

I got E11000 duplicate key error collection
Mongoose 7.3.3 has no such error

Expected Behavior

New object in inserted without error and id field will be ignored

[vkarpov15]

In Mongoose 7.4, we made it possible to modify the document's _id property via id. doc.id = 42 is now equivalent to doc._id = 42;. However, I can see this causing trouble if you use new MyModel(obj) and obj contains both id and _id properties. We'll fix it so that new MyModel(obj) ignores id if _id is set.

[salos1982]

I would prefer to have option to disable such functionality. I have a lot of code where I get objects with id field and then insert them to database. And very often there are ids of previous objects and it causes duplicate key errors.

[zeljkocurcic]

Please consider releasing a major version when doing something like this in the future and making sure it's marked as a breaking change.

[vkarpov15]

@zeljkocurcic we didn't see this as a breaking change when we released it, but in hindsight we definitely should have. We removed this id setter in Mongoose 8.

[tonynelson19]

Can the Migrating from 6.x to 7.x migration guide be updated to reference this breaking change?

[mete89]

Hey @vkarpov15

The first doc doesn't include [id setter] section. You may want to update it as well.
https://mongoosejs.com/docs/migrating_to_7.html
https://mongoosejs.com/docs/7.x/docs/migrating_to_7.html

Lastly, what is the suggested migration path from version 6 to avoid being affected by the ID setter change? Is there any option introduced to globally disable it in version 7?

[vkarpov15]

@mete89 the idsetter section was added in da126f4, we just need to merge that to master.

Do you rely on the .id property? if not, the easiest way would be to simply disable the id property for all documents by default:

mongoose.set('id', false);

If you rely on the .id property, you can disable Mongoose's default id property and add your own as follows.

mongoose.set('id', false);
mongoose.plugin(schema => {
  schema.virtual('id').get(function() { return this._id?.toString(); });
});

[mete89]

@vkarpov15 My models have an id field to represent ids in another context so I don't need any virtual here. I set them while creating my objects. So how can I migrate to 7 by disabling this unwanted feature?

id: String,

[mete89]

I upgraded directly to 8.x.x to prevent this issue.

[vkarpov15]

@mete89 schema.virtual('id').get(function() { return this._id.toString(); })