knex-postgres-multi-tenancy

Provides a way of implementing multi-tenancy using table prefixes for Postgres.

This library was based on bravi-software/knextancy. It was refactored to a more light-weight library using:

• Typescript
• Latest Knex version
• Prettier
• New tests
• Docker-compose
• Removed MySql support
• Removed the ability to fetch all tenants names
• Remove the ability to run all migrations
• Updated npm scripts

import knex from 'knex'
import knexMultiTenancy from 'knex-postgres-multi-tenancy'

const knexConnection = knex(YOUR_KNEX_CONFIGURATION)

const tenantKnex = await knexMultiTenancy.tenant(knexConnection, tenantId)

// the tenantKnex object contains the tenantId as an attribute
console.log(tenantKnex.tenantId)

const users = await tenantKnex('$_users')
  .where({
    first_name: 'Test',
    last_name: 'User',
  })
  .select('id')

Its tenant method expects a knex connection instance and a tenantId and returns Promise for a tenantKnex instance that scopes every queries to the particular tenant.

The only requirement is that every query is written using the special $_ prefix for every table name.

Migrations

knex-postgres-multi-tenancy assures that all migrations run for the tenant before returning its knex instance.

This special naming convention also applies while writing migrations, for example:

import Knex from 'knex'

export const up = (knex: Knex) =>
  knex.schema.createTable('$_users', (table) => {
    table.increments('id').primary()
    table.string('name')
  })

export const down = (knex: Knex) => knex.schema.dropTable('$_users')

Connect Middleware

It also provides a handy Connect middleware that automatically creates a knex instance and attaches it to the request object for a given tenant based on a special HTTP header.

Bellow is a usage example:

const app = express()

app.use(knexMultiTenancy.middleware(knex, { header: 'x-client-id' }))

app.get('/', function (req, res, next) {
  req.knex
    .select()
    .from('$_users')
    .then(function (users) {
      res.send(users)
    }, next)
})

The knexMultiTenancy.middleware expects two parameters:

• knex connection instance;
• options.header the name of the HTTP header that will contain the tenant id.

Tests

To run the tests using Docker Compose:

npm run dnpm i
npm run dt