feat: auto fetching for future commits

+ Introduced a new auto fetch script that will automatically fetch and pull any commits pushed to GitHub.
+ Ensures token matches from the webhook.
+ Configurable via .env where necessary.

autofetch-script/fetch-script.js

@@ -0,0 +1,36 @@
+require("dotenv").config();
+const { exec } = require('child_process');
+const crypto = require('crypto');
+const express = require('express');
+const cookieParser = require('cookie-parser');
+const cors = require('cors');
+
+// Express Setup & Config
+const app = express();
+app.use(cookieParser());
+app.use(cors());
+app.use(express.json({limit: '50mb'}));
+app.listen(5000);
+
+// POST listener from GitHub
+console.log("Started fetch listener successfully...")
+app.post('/fetch-gh', (req, res) => {
+    console.log("Received webhook POST request...")
+
+    var hmac, calculatedSignature, payload = req.body;
+    hmac = crypto.createHmac('sha1', process.env.GH_WEBHOOK_SECRET);
+    hmac.update(JSON.stringify(payload));
+    calculatedSignature = 'sha1=' + hmac.digest('hex');
+
+    // Ensure that the secret is valid
+    if (req.headers['x-hub-signature'] === calculatedSignature) {
+        console.log("Authenticated webhook, secret matches, fetching and pulling git...")
+        exec(`cd ${process.env.WORK_DIR} && git fetch && git pull`)
+    }
+    
+    else {
+        console.log("Authentication failed... secret not matching")
+    }
+    
+    res.sendStatus(201)
+})