run.js

const express = require('express');
const { MongoClient } = require('mongodb');

// Initialize Express app
const app = express();
const port = 3000;

// MongoDB Connection URL and Database Name
const url = 'mongodb://localhost:27017';
const dbName = 'app_db';
const collectionName = 'packages';

app.use(express.json());

async function connectDB() {
    const client = new MongoClient(url);
    await client.connect();
    return client.db(dbName).collection(collectionName);
}

app.get('/api/data', async (req, res) => {
    let limit = parseInt(req.query.limit) || 10;
    limit = Math.min(limit, 20);
    const page = parseInt(req.query.page) || 1;
    const skip = (page - 1) * limit;

    const query = {};

    // Handle the 'query' parameter for wildcard searches
    if (req.query.query) {
        const searchValue = req.query.query;
        query.reason = { $regex: searchValue.replace(/%/g, '.*'), $options: 'i' };
    }

    const collection = await connectDB();

    try {
        const cursor = collection.find(query).skip(skip).limit(limit);
        const results = await cursor.toArray();

        // Calculate pagination info
        const totalDocuments = await collection.countDocuments(query);
        const totalPages = Math.ceil(totalDocuments / limit);

        // Calculate prevPage and nextPage
        const prevPage = page > 1 ? page - 1 : null;
        const nextPage = page < totalPages ? page + 1 : null;

        // Response object structure
        const responseObject = {
            code: 200,
            status: 'success',
            data: results,
            pagination: {
                total: totalDocuments,
                totalPages: totalPages,
                currentPage: page,
                perPage: limit,
                prevPage: prevPage,
                nextPage: nextPage
            }
        };

        res.json(responseObject);
    } catch (err) {
        console.error('Error fetching data:', err);
        res.status(500).json({ code: 500, status: 'error', message: 'Internal server error' });
    }
});

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