MongoDB Connection with Retry

javascript Copy Code

const mongoose = require('mongoose');

const MAX_RETRIES = 5;
const RETRY_DELAY = 3000;

async function connectDB(retryCount = 0) {
    try {
        await mongoose.connect(process.env.MONGO_URI, {
            maxPoolSize: 10,
            serverSelectionTimeoutMS: 5000,
            socketTimeoutMS: 45000,
        });
        console.log('MongoDB connected successfully');

        mongoose.connection.on('error', (err) => {
            console.error('MongoDB connection error:', err);
        });

        mongoose.connection.on('disconnected', () => {
            console.warn('MongoDB disconnected. Attempting reconnect...');
        });
    } catch (err) {
        console.error(`MongoDB connection attempt ${retryCount + 1} failed:`, err.message);
        if (retryCount < MAX_RETRIES) {
            console.log(`Retrying in ${RETRY_DELAY / 1000}s...`);
            await new Promise(r => setTimeout(r, RETRY_DELAY));
            return connectDB(retryCount + 1);
        }
        throw new Error('Failed to connect to MongoDB after max retries');
    }
}

process.on('SIGINT', async () => {
    await mongoose.connection.close();
    console.log('MongoDB connection closed gracefully');
    process.exit(0);
});

module.exports = connectDB;

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