Fixing SequelizeConnectionRefusedError When Connecting to PostgreSQL in Node.js

I'm developing a Node.js backend using Express and Sequelize to connect to a PostgreSQL database. When I run node index.js, I get a SequelizeConnectionRefusedError.

I have verified that PostgreSQL is running on port 5432 and that the credentials are correct (even trying localhost and 127.0.0.1). Despite checking pg_hba.conf and ensuring psql login works, I still receive the ECONNREFUSED error.

Below are the key parts of my project:

1. index.js:

JAVASCRIPTCopied
import express from 'express';
import pool from './db/db.js';
import cors from 'cors';
import authRoutes from './routes/authRoutes.js';
import userRouter from './routes/userRoutes.js';
import productRoutes from './routes/productRoutes.js';
import orderRoutes from './routes/orderRoutes.js';
import cartRoutes from './routes/cartRoutes.js';

const app = express();
const PORT = 3000;

app.use(express.json());
app.use(
    cors({
      origin: 'http://localhost:8081',
      credentials: true,
    })
);

// Testing DB Connection;
app.get('/api/test-db', async (req, res) => {
    try {
        const result = await pool.query("SELECT NOW()");
        res.json({ message: "Database connected!", time: result.rows[0].now });
    } catch (error) {
        console.error('Error connecting to the database:', error.stack);
        res.status(500).json({ message: "Database connection error!" });
    }
});

app.use('/api/auth', authRoutes);
app.use('/api/user', userRouter);
app.use('/produce', productRoutes);
app.use('/orders', orderRoutes);
app.use('/cart', cartRoutes);

app.listen(PORT, () => {
    console.log(`Server is running on http://localhost:${PORT}`);
});

2. Error Message:

BASHCopied
Server is running on http://localhost:3000
Unable to connect to the database: ConnectionRefusedError [SequelizeConnectionRefusedError]
    at Client._connectionCallback (D:\Farm-Bridge-App\Farm-Bridge-App\Backend\node_modules\sequelize\lib\dialects\postgres\connection-manager.js:133:24)
    at Client._handleErrorWhileConnecting (D:\Farm-Bridge-App\Farm-Bridge-App\Backend\node_modules\pg\lib\client.js:326:19)
    ...
  parent: AggregateError [ECONNREFUSED]:
      at internalConnectMultiple (node:net:1118:18)
      at afterConnectMultiple (node:net:1685:7) {
    code: 'ECONNREFUSED',
  },
  original: AggregateError [ECONNREFUSED]:
      at internalConnectMultiple (node:net:1118:18)
      at afterConnectMultiple (node:net:1685:7) {
    code: 'ECONNREFUSED',
  }

3. db.js (Database Connection):

JAVASCRIPTCopied
import { Sequelize } from 'sequelize';

const sequelize = new Sequelize('farmbridge_app', 'postgres', 'myPostgres', {
  host: 'localhost',
  dialect: 'postgres',
});

// Function to test the database connection
const testConnection = async () => {
  try {
    await sequelize.authenticate();
    console.log('Connection has been established successfully.');

    // Synchronize the models with the database
    await sequelize.sync({ alter: true }); // alter: true matches schema to the models
    console.log('All models were synchronized successfully.');
  } catch (error) {
    console.error('Unable to connect to the database:', error);
  }
};

// Run the connection test
testConnection();

export default sequelize;

One of the answers mentioned that the issue might be due to importing the wrong module in index.js. It suggests replacing:

JAVASCRIPTCopied
import pool from './db/db.js';

with:

JAVASCRIPTCopied
import sequelize from './db/db.js';

If anyone has further insights or recommendations about this connection issue, please help clarify the solution.