bookshelf-paranoia

Protect your database from data loss by soft deleting your rows.

Installation

After installing bookshelf-paranoia with npm i --save bookshelf-paranoia, all you need to do is add it as a bookshelf plugin and enable it on your models. The default field used to soft delete your models is deleted_at but you can override that.

let knex = require('knex')(require('./knexfile.js').development)
let bookshelf = require('bookshelf')(knex)

// Add the plugin
bookshelf.plugin(require('bookshelf-paranoia'))

// Enable it on your models
let User = bookshelf.Model.extend({ tableName: 'users', softDelete: true })

Usage

You can call every method as usual and bookshelf-paranoia will handle soft deletes transparently for you.

// This user is indestructible
yield User.forge({ id: 1000 }).destroy()

// Now try to find it again
let user = yield User.forge({ id: 1000 }).fetch() // null

// It won't exist, even through eager loadings
let user = yield User.forge({ id: 2000 }).fetch() // undefined

let blog = yield Blog.forge({ id: 2000 }).fetch({ withRelated: 'users' })
blog.related('users').findWhere({ id: 1000 }) // also undefined

// But we didn't delete it from the database
let user = yield knex('users').select('*').where('id', 1000)
console.log(user[0].deleted_at) // Fri Apr 15 2016 00:40:40 GMT-0300 (BRT)

Overrides

bookshelf-paranoia provides a set of overrides so you can customize your experience while using it.

// Override the field name that holds the deletion date
bookshelf.plugin(require('bookshelf-paranoia'), { field: 'deletedAt' })

// If you want to delete something for good, even if the model has soft deleting on
yield User.forge({ id: 1000 }).destroy({ hardDelete: true })

// Retrieve a soft deleted row even with the plugin enabled. Works for
// eager loaded relations too
let user = yield User.forge({ id: 1000 }).fetch({ withDeleted: true })

// By default soft deletes also emit "destroying" and "destroyed" events. You
// can easily disable this behavior when setting the plugin
bookshelf.plugin(require('bookshelf-paranoia'), { events: false })

// Disable only one event
bookshelf.plugin(require('bookshelf-paranoia'), {
  events: { destroying: false }
})

// Enable saving, updating, saved, and updated. This will turn on all events
// since destroying and destroyed are already on by default
bookshelf.plugin(require('bookshelf-paranoia'), {
  events: {
    saving: true,
    updating: true,
    saved: true,
    updated: true
  }
})

Sentinels/Uniqueness

Due to limitations with some DBMSes, constraining a soft-delete-enabled model to "only one active instance" is difficult: any unique index will capture both undeleted and deleted rows. There are ways around this, e.g., scoped indexes (WHERE deleted_at IS NULL), but the most portable method involves adding a so-called sentinel column: a field that is true/1 when the row is active and NULL when it has been deleted. Since unique indexes do not consider null fields, this allows a compound unique index to fulfill our needs: indexing ['email', 'active'] will ensure only one unique active email at a time, for example.

To maintain backward compatibility, sentinel functionality is disabled by default. It can be enabled globally by setting the sentinel config value to the name of the sentinel column, nominally "active". The sentinel column should be added to all soft-deletable tables via migration as a nullable boolean field.

// Enable sentinel values stored under "active"
bookshelf.plugin(require('bookshelf-paranoia'), { sentinel: 'active' })

let user = yield User.forge().save()
user.get('active')  // will be true

yield user.destroy()
user.get('active')  // will be false

Detecting soft deletes

By listening to the default events emitted by bookshelf when destroying a model you're able to detect if that model is being soft deleted.

let model = new User({ id: 1000 })

// Watch for deletes as usual
model.on('destroying', (model, options) => {
  if (options.softDelete) console.log(`User ${model.id} is being soft deleted!`)
})

model.on('destroying', (model, options) => {
  if (options.softDelete) console.log(`User ${model.id} has been soft deleted!`)
})

yield model.destroy()
// User 1000 is being soft deleted!
// User 1000 has been soft deleted!

Testing

git clone [email protected]:bsiddiqui/bookshelf-paranoia.git
cd bookshelf-paranoia && npm install && npm test

dantman / bookshelf-paranoia Goto Github PK