A Url shortener Made Using Node.js and Firebase realtime database

npm init
npm install firebase-admin

create a project in firebase. goto firestore database and create a database. Now goto project settings, then goto service accounts. Select Node.js, then generate new private key. Save the private key. it will automatically download in JSON format.

Create a file : main.js(Node server)

const http = require('http');
const admin = require('firebase-admin');
const querystring = require('querystring');
const serviceAccount = require('./firebase-private-key.json');
admin.initializeApp({
credential: admin.credential.cert(serviceAccount),
databaseURL: "Yout database url"
});
const db = admin.firestore();// Initializing the firebase database
const PORT = process.env.PORT || 3000;
// this is the request and response created for the server. Basically all the changes that is going to happen in the DOM is controller in by this single const server.
const server = http.createServer((req, res) => {
console.log(req.headers); // Log the headers object to check if it contains the host property
headurl = http://${req.headers.host};
console.log(headurl); // Log the constructed URL for debugging purposes
if (req.url === '/submit') {
let body = '';
req.on('data', chunk => {
body += chunk.toString();
});
req.on('end', () => {
const data = querystring.parse(body);
const longurl = data.longurl;
let lmao = generateKey();
shortenUrl(longurl, res, lmao);
});
} else if (req.url !== '/' && req.url !== '/submit') {
const shorturl = req.url.slice(1);
redirectingurl(res, shorturl);
} else {
res.writeHead(200, {'Content-Type': 'text/html'});
res.write(<h1>Add your longurl to the database</h1> <form method="POST" action="/submit"> <label for="longurl">longurl:</label> <input type="text" id="longurl" name="longurl"> <button type="submit">Submit</button> </form>);
res.end();
}
});
server.listen(PORT, () => {
console.log('Server is listening on port 3000');
});
function generateKey() {
const chars = 'abcdefghijklmnopqrstuvwxyz0123456789';
let key = '';
for (let i = 0; i < 4; i++) {
const randomIndex = Math.floor(Math.random() * chars.length);
key += chars[randomIndex];
}
return key;
}
function shortenUrl(longURL, res, lmao) {
const query = db.collection("urls").where("longURL", "==", longURL);
// Check if longURL already exists in the database
query.get().then(function(querySnapshot) {
if (!querySnapshot.empty) {
// If the longURL already exists, get its corresponding shorturl and display it
const shorturl = querySnapshot.docs[0].data().short;
console.log(shorturl);
res.writeHead(200, {'Content-Type': 'text/html'});
res.write(<h1>Hello ${longURL}!${lmao}</h1> <p>Your shorturl is: <a href="${shorturl}">${shorturl}</a></p>);
res.end();
} else {
// If the longURL doesn't exist, generate a new shorturl and add it to the database
const shorturl = generateKey();
const query = db.collection("urls").where("shorturl", "==", shorturl);
  // Check if the generated shorturl already exists in the database
  query.get().then(function(querySnapshot) {
    if (!querySnapshot.empty) {
      // If the shorturl already exists, generate a new one and try again
      shortenUrl(longURL, res, lmao);
    } else {
      // If the shorturl doesn't exist, add the new entry to the database
      db.collection("urls").add({
        longURL: longURL,
        short: shorturl
      }).then(function(docRef) {
        console.log("Document written with ID: ", docRef.id);
        res.writeHead(200, {'Content-Type': 'text/html'});
        res.write(`
          <h1>Hello ${longURL}!${lmao}</h1>
          <p>Your shorturl is: <a href="${shorturl}">${shorturl}</a></p>
        `);
        res.end();
      })
      .catch(function(error) {
        console.error("Error adding document: ", error);
        res.writeHead(500, {'Content-Type': 'text/plain'});
        res.write('Error adding document to database');
        res.end();
      });
    }
    });
  }

});
}
function redirectingurl(res, shorturl){
//show all data in the coolection urls
// db.collection("urls").get().then((querySnapshot) => {
//   querySnapshot.forEach((doc) => {
//     console.log(${doc.id} => ${doc.data().longURL});
//       console.log(${doc.id} => ${doc.data().longURL});
//   });
// });
//check if shorturl exists in database
const query = db.collection("urls").where("short", "==", shorturl);
query.get().then(function(querySnapshot) {
if (!querySnapshot.empty) {
// If the shorturl already exists, get its corresponding longurl and redirect
const longurl = querySnapshot.docs[0].data().longURL;
console.log(longurl);
res.writeHead(302, { 'Location': longurl});
res.end();
} else {
// If the shorturl doesn't exist, redirect to homepage
res.writeHead(302, { 'Location': '/'});
console.log(shorturl + " doesn't exist")
res.end();
}
});
}

Shreyaanp/urlshortener-Firebase

A Url shortener Made Using Node.js and Firebase realtime database

Create a file : main.js(Node server)