How to delete related documents in mongodb like onDelete: cascade?-CodePudding

I use mongodb and mongoose ORM in my project. I have two related collections.

My first collection like this.

const Sensor: Schema = new Schema(
  {
    name: {
      type: String,
    },
    description: {
      type: String,
      default: null,
    },
    deviceId: {
      type: mongoose.Types.ObjectId,
      required: true,
      ref: 'Device',
    },
  },
  {
    timestamps: true,
    versionKey: false,
    collection: 'Sensor',
  }
);

Other collection like this.

const Device: Schema = new Schema(
  {
    name: {
      type: String,
      required: true,
      unique: true,
    },
  },
  {
    versionKey: false,
    collection: 'Device',
  }
);

The sensor has the id of the device and this two collections are related.

When I delete a device, I want the associated sensors to be deleted as well. (like onDelete: cascade feature, in sequelize and typeorm)

How can I do it with mongoose? What's best practices for this issue?

CodePudding user response：

Implement the necessary middleware for cleaning up reference to related documents

For example, when using the Document.remove method to delete a device,
implement a post remove hook to remove all related sensors devices as follows:

Device.post('remove', function(doc, next) {

  // Deleting related sensors. 
  Sensor.deleteMany({ deviceId: doc._id })
    .then(() => next())
    .catch(next);
 
});