PSI Notification Server

A custom module for real-time notifications built with Express, Socket.IO, and Sequelize. This module provides a methods to manage notifications with support for real-time updates via WebSockets.

Features

• Create, update, delete, and fetch notifications.
• Real-time notifications via WebSockets.
• Simple integration with an Express app.
• CORS management for different environments (production, development).
• Sequelize-based ORM for easy interaction with the database.

Prerequisites

• Node.js >= 14.x
• PostgreSQL or any other supported database for Sequelize
• Express.js
• Socket.IO

Installation

To integrate this module into your Express app:

1. Install the module:

   Using npm:

   npm install psi-notification-server

   Or using yarn

   yarn add psi-notification-server

2. Set up environment variables: Add the following environment variables to your .env file (or in the server environment):

   DB_CONNECTION_STRING=postgres://username:password@localhost:5432/<dbname>
   NODE_ENV=development  # or 'production'

Available Methods:

import { initNotificationModule } from 'psi-notification-server';

const { initializeSocket, addNotification, getNotificationList, updateNotificationStatus, deleteNotification } =
    await initNotificationModule('database-connection-string');

Initialize Socket Connection:

const app = express();
const server = http.createServer(app);
initializeSocket(server);

Notification Props (Interface):

interface NotificationProps {
    receiver_id: number;
    sender_id: number;
    title: string;
    message: string;
    image_url?: string;
    redirect_route?: string;
    type?: string;
    status?: string;
    created_at?: Date;
    updated_at?: Date;
}

Create Notification:

Method: addNotification()

Required Params

notificationData: NotificationProps,
userId?: string

Example

const result = await addNotification(notificationData, userId);

Read Notification:

Method: getNotificationList()

Required Params

receiverId: string,
page: number = 1,
pageSize: number = 10,
status?: string[]       // ['new', 'unread', 'read']

Example

const { data, error } = await getNotificationList('receiverId', 1, 15, ['new', 'unread', 'read']);

Update Notification:

Method: updateNotificationStatus()

Required Params

receiverId: string;
status: string;
notificationIds?: string[]; // Optional

Example

const result = await updateNotificationStatus({
    receiverId,
    'read',
    ['notificationId_1', 'notificationId_2', ...],
});

Delete Notification:

Method: deleteNotification()

Required Params

notificationId: string;

Example

const result = await deleteNotification(notificationId);

Usage

Example: Using the Notification Module in Express

Here’s an example of how to set up and use the notification module in an Express app:

import express, { Request, Response } from 'express';
import http from 'http';
import { initNotificationModule } from 'psi-notification-server';
import cors from 'cors';
import dotenv from 'dotenv';

dotenv.config();

// Setup the database connection string
const connectionString = process.env.DATABASE_URL;

if (!connectionString) {
  throw new Error('DATABASE_URL is not defined in .env');
}

const app = express();
const server = http.createServer(app);

// Middleware and CORS setup
app.use(express.json());
app.use(cors({ origin: '*', methods: ['GET', 'POST', 'PUT'], credentials: true }));

// Initialize Notification Module
async function initializeNotificationModuleAndRoutes() {
  try {
    const { initializeSocket, getNotificationList, updateNotificationStatus, addNotification, deleteNotification } = await initNotificationModule(connectionString);

    // Initialize Socket.IO
    initializeSocket(server);

    // Define the notification routes
    app.get('/notifications/list/:receiverId', async (req: Request, res: Response) => {
      const { receiverId } = req.params;
      const { page = '1', pageSize = '10', status } = req.query;
      const statusArray = status ? String(status).split(',') : ['new'];

      const { data, error } = await getNotificationList(receiverId, Number(page), Number(pageSize), statusArray);
      if (error) return res.status(500).json({ message: error });
      return res.status(200).json({ data });
    });

    // Insert a new notification
    app.post('/notifications/insert', async (req: Request, res: Response) => {
      const { notification, userId } = req.body;
      const requiredFields: (keyof INotification)[] = ['receiver_id', 'sender_id', 'title', 'message', 'status'];
      const missingFields = requiredFields.filter((field) => !notification[field]);

      if (missingFields.length > 0) {
        return res.status(400).json({ error: `Missing required fields: ${missingFields.join(', ')}` });
      }

      const result = await addNotification(notification, userId);  // userId is optional
      return res.json({ data: result.data, error: result.error });
    });

    // Start the server
    server.listen(process.env.PORT, () => {
      console.log('Server is running on port 3001');
    });
  } catch (error) {
    console.error('Error initializing notification module:', error);
  }
}

// Call the initialization function
initializeNotificationModuleAndRoutes();