Add validation to a smart field edition

Please be sure of your agent type and version and pick the right documentation accordingly.

This is the documentation of the forest-express-sequelize and forest-express-mongoose Node.js agents that will soon reach end-of-support.

forest-express-sequelize v9 and forest-express-mongoose v9 are replaced by @forestadmin/agent v1.

Please check your agent type and version and read on or switch to the right documentation.

Add validation to a smart field edition

Context: I want to make sure that my users can only enter a value satisfying a certain set of conditions when editing a smart field.

Here I'm working on a collection customers and the smart field 'must-be-kuku' should only accept the value kuku.


const { collection } = require('forest-express-sequelize');
const models = require('../models');

// This file allows you to add to your Forest UI:
// - Smart actions: <>
// - Smart fields: <>
// - Smart relationships: <>
// - Smart segments: <>
collection('customers', {
  actions: [],
  fields: [
      field: 'must-be-kuku',
      type: 'String',
      get(customer) {
        return 'kuku';
      set(customer, value) {},
  segments: [],

At the route level I need to check the user input from the edit form in the UI and check the value that has been entered into the field 'must-be-kuku'.


const express = require('express');
const { PermissionMiddlewareCreator } = require('forest-express-sequelize');
const { customers } = require('../models');

const router = express.Router();
const permissionMiddlewareCreator = new PermissionMiddlewareCreator(

// Update a Customer
  (request, response, next) => {
    if (['must-be-kuku'] !== 'kuku') {
      return response.status(403).send('should have been kuku!');

module.exports = router;

Last updated