Deploy the Yakult App Backend Server

The Yakult App backend is an Express.js REST API that connects to a MySQL database and exposes all endpoints consumed by the mobile client. It handles authentication via JWT, manages sales orders, products, clients, and generates reports. Before starting the mobile app, you must have this server running and reachable on your network.

Prerequisites

Node.js 18+ — nodejs.org
MySQL 8 — via XAMPP, MySQL Workbench, or a standalone MySQL Server installation
npm (bundled with Node.js)

Setup

Clone the repository

Clone the project and navigate into the root folder.

git clone https://github.com/your-org/yakult-app.git
cd yakult-app

Install backend dependencies

Move into the backend directory and install all required Node.js packages.

cd backend && npm install

Configure the MySQL connection

Open backend/db.js and update the connection pool options to match your local MySQL installation.

const mysql = require('mysql2/promise');

const pool = mysql.createPool({
  host: '127.0.0.1',   // Change if MySQL is on a remote host
  port: 3306,           // Default MySQL port
  user: 'root',         // Your MySQL username
  password: '',         // Your MySQL password
  database: 'yakult_db',
  waitForConnections: true,
  connectTimeout: 10000,
});

module.exports = pool;

Change host, user, password, and database to match your environment. See the Database setup guide for full details on creating yakult_db.

Set the JWT secret

The backend signs all authentication tokens using the JWT_SECRET environment variable. You can set it inline for a quick start or via a .env file for persistent configuration.Inline (terminal session only):

# macOS / Linux
export JWT_SECRET=your-strong-secret-here
npm start

# Windows (Command Prompt)
set JWT_SECRET=your-strong-secret-here
npm start

# Windows (PowerShell)
$env:JWT_SECRET="your-strong-secret-here"
npm start

Using a .env file (recommended):Create a file named .env inside the backend/ directory:

JWT_SECRET=your-strong-secret-here

Then install dotenv and add require('dotenv').config() at the top of server.js, or use a package such as dotenv-cli to load it automatically.

Environment variables reference

Variable	Default	Description
`JWT_SECRET`	`yakult-reportes-dev-secret`	Secret key used to sign and verify JWT tokens

Never use the default JWT_SECRET in production. The default value yakult-reportes-dev-secret is public knowledge — any attacker could forge valid tokens. Always set a long, random secret before deploying to a production or staging environment.

Start the server

Run the server in development mode (with auto-reload via nodemon) or in production mode.

npm run dev

A successful startup prints:

Servidor corriendo en http://localhost:3000

On every startup, ensureSchema() runs automatically before the server begins accepting requests. It creates all 7 required database tables if they do not yet exist, adds any missing columns to existing tables, and creates missing indexes — all operations are fully idempotent and will never delete or overwrite your existing data. See the Database guide for a full breakdown of what this migration does.

Verify the server is running

Send a quick health-check request to confirm the API is responding.

curl http://localhost:3000/

Expected response:

{ "ok": true, "mensaje": "API Yakult funcionando ✅" }

If the server started but MySQL is unreachable, the process will exit before accepting any connections and print an error to the console:

No se pudo preparar la base de datos: Error: connect ECONNREFUSED 127.0.0.1:3306

Ensure MySQL is running and that the credentials in backend/db.js are correct, then start the server again.

Setup

Documentation Index

​Prerequisites

​Setup

​Environment variables reference

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Prerequisites

Setup

Environment variables reference