Upload files to AWS S3

This example shows you how to implement a smart action to upload image files to an AWS S3 bucket. Here we have a companies model that has two fields corresponding to files stored in an AWS S3 bucket:

  • A certificate of incorporation

  • A proof of identity

We implemented a smart action to upload the files for each company.


  • An admin backend running on forest-express-sequelize

  • An AWS S3 bucket with access credentials

  • The aws-sdk npm package

  • The bluebird npm package

  • The parse-data-uri npm package

How it works

Directory: /models

This directory contains the companies.js file where the companies model is declared.

module.exports = (sequelize, DataTypes) => {
const { Sequelize } = sequelize;
const Companies = sequelize.define('companies', {
name: {
type: DataTypes.STRING,
industry: {
type: DataTypes.STRING,
headquarter: {
type: DataTypes.STRING,
status: {
type: DataTypes.STRING,
description: {
type: DataTypes.STRING,
createdAt: {
type: DataTypes.DATE,
updatedAt: {
type: DataTypes.DATE,
certificateOfIncorporationId: {
type: DataTypes.UUID,
passportId: {
type: DataTypes.UUID,
}, {
tableName: 'companies',
underscored: true,
schema: process.env.DATABASE_SCHEMA,
return Companies;

Directory: /forest

This directory contains the companies.js file where the smart action Upload Legal Docs is declared.

You need to specify that the widget file picker is applicable to the input field used to upload the file.

const { collection } = require('forest-express-sequelize');
collection('companies', {
actions: [
name: 'Upload Legal Docs',
type: 'single',
fields: [{
field: 'Certificate of Incorporation',
description: 'The legal document relating to the formation of a company or corporation.',
type: 'File',
isRequired: true,
}, {
field: 'Valid proof of ID',
description: 'ID card or passport if the document has been issued in the EU, EFTA, or EEA / ID card or passport + resident permit or driving licence if the document has been issued outside the EU, EFTA, or EEA of the legal representative of your company',
type: 'File',
isRequired: true,
fields: [],
segments: [],

Directory: /services

This directory contains an s3-helper.js file where the methods to upload files to s3 is declared.

You need to configure your AWS credentials inside your app to get access to your bucket. You can read more about it in the AWS documentation here.

const P = require('bluebird');
const parseDataUri = require('parse-data-uri');
const AWS = require('aws-sdk');
function S3Helper() {
this.upload = (rawData, filename) => new P((resolve, reject) => {
// Create the S3 client.
const s3Bucket = new AWS.S3({ params: { Bucket: process.env.S3_BUCKET } });
const parsed = parseDataUri(rawData);
const base64Image = rawData.replace(/^data:(image|application)\/\w+;base64,/, '');
const data = {
Key: filename,
Body: new Buffer(base64Image, 'base64'),
ContentEncoding: 'base64',
ContentDisposition: 'inline',
ContentType: parsed.mimeType,
// Upload the image.
s3Bucket.upload(data, (err, response) => {
if (err) {
return reject(err);
return resolve(response);
module.exports = S3Helper;

Directory: /routes

This directory contains the companies.js file where the logic of the smart action is implemented.

const express = require('express');
const { PermissionMiddlewareCreator } = require('forest-express-sequelize');
const { companies } = require('../models');
const uuid = require('uuid/v4');
const S3Helper = require('../services/s3-helper');
const P = require('bluebird');
const router = express.Router();
const permissionMiddlewareCreator = new PermissionMiddlewareCreator('companies');
function uploadLegalDoc(companyId, doc, field) {
const id = uuid();
//upload the files using the helper
return new S3Helper().upload(doc, `livedemo/legal/${id}`)
//once the file is uploaded, update the relevant company field with the file id
.then(() => companies.findByPk(companyId))
.then((company) => {
company[field] = id;
return company.save();
.catch((e) => e);
router.post('/actions/upload-legal-docs', permissionMiddlewareCreator.smartAction(), (req, res) => {
// Get the current company id
const companyId = req.body.data.attributes.ids[0];
// Get the values of the input fields entered by the admin user.
const attrs = req.body.data.attributes.values;
const certificateOfIncorporation = attrs['Certificate of Incorporation'];
const passportId = attrs['Valid proof of ID'];
uploadLegalDoc(companyId, certificateOfIncorporation, 'certificateOfIncorporationId'),
uploadLegalDoc(companyId, passportId, 'passportId'),
.then(() => {
// Once the upload is finished, send a success message to the admin user in the UI.
return res.send({ success: 'Legal documents are successfully uploaded.' });
module.exports = router;