Proxy External API to Bypass CORS and Secure Keys

// server.js (Node.js with Express)
const express = require('express');
const axios = require('axios');
const cors = require('cors');
require('dotenv').config(); // For environment variables

const app = express();
const PORT = process.env.PORT || 3001;

// Enable CORS for client-side requests
app.use(cors());
app.use(express.json());

// Proxy endpoint for an external API
app.get('/api/external-data', async (req, res) => {
    try {
        const externalApiKey = process.env.EXTERNAL_API_KEY; // Keep API key server-side
        const externalApiUrl = 'https://api.example.com/data'; // Replace with actual API URL

        const response = await axios.get(externalApiUrl, {
            headers: {
                'Authorization': `Bearer ${externalApiKey}`,
                // Add other necessary headers for the external API
            },
            params: req.query // Pass client-side query parameters to external API
        });

        res.json(response.data);
    } catch (error) {
        console.error('Error proxying external API:', error.message);
        res.status(error.response?.status || 500).json({
            message: 'Failed to fetch external data',
            error: error.message
        });
    }
});

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

// Example .env file:
// EXTERNAL_API_KEY=your_secret_api_key_here