@anhkhoakz/mongoose-to-json

A Mongoose plugin to customize the toJSON output.

Installation

You can install this package using bun, yarn, or npm.

# bun
bun add @anhkhoakz/mongoose-to-json

# yarn
yarn add @anhkhoakz/mongoose-to-json

# npm
npm install @anhkhoakz/mongoose-to-json --save

Usage

Setup as a global plugin for specific Mongoose schemas:

import mongoose from 'mongoose'
import { toJSON } from '@anhkhoakz/mongoose-to-json'
const { Schema } = mongoose

// Define schema
const MySchema = new Schema({
  name: String,
  email: String
})

// Apply plugin
MySchema.plugin(toJSON)

Default Transformations

This plugin will normalize JSON output for client-side applications from:

{
  "_id": "400e8324a71d4410b9dc3980b5f8cdea",
  "__v": 2,
  "name": "Item A"
}

To a cleaner:

{
  "id": "400e8324a71d4410b9dc3980b5f8cdea",
  "name": "Item A"
}

By default, the plugin:

• Removes __v (version field)
• Converts _id to id
• Removes private paths

Configuration Options

You can configure which transformations to apply by setting options:

import mongoose from 'mongoose'
import { toJSON } from '@anhkhoakz/mongoose-to-json'
const { Schema } = mongoose

const schema = new Schema({
  email: { type: String },
  password: { type: String, private: true },
  name: String
})

// Disable specific transformations
schema.plugin(toJSON, {
  toJSON: {
    removeVersion: false,      // Keep __v field
    normalizeId: false,        // Keep _id field
    removePrivatePaths: false  // Keep private paths
  }
})

Private Paths

The plugin automatically removes fields marked as private:

const schema = new Schema({
  email: { type: String },
  password: { type: String, private: true },
})

schema.plugin(toJSON)

const User = mongoose.model('users', schema)
const user = new User({ email: '[email protected]', password: 'secret' })

console.log(user.toJSON())

This will output:

{
  "id": "400e8324a71d4410b9dc3980b5f8cdea",
  "email": "[email protected]"
}

Custom Transform Function

You can use the plugin with your own custom transform function:

schema.plugin(toJSON, {
  toJSON: {
    transform: (doc, ret) => {
      // Your custom transformations
      ret.customField = 'custom value'
      return ret
    }
  }
})

API Reference

toJSON(schema: Schema, options?: ToJSONOptions)

Applies the toJSON plugin to a Mongoose schema.

Options

• removeVersion?: boolean - Remove __v field (default: true)
• normalizeId?: boolean - Convert _id to id (default: true)
• removePrivatePaths?: boolean - Remove private paths (default: true)
• transform?: TransformFunction - Custom transform function

License

Apache License 2.0

Copyright (c) anhkhoakz