URL Shortener using Flask – with Source Code – 2022

Machine Learning Projects

Hello guys, in today’s blog we will build a URL Shortener using Flask. This will be an exciting blog, so without any further due, let’s do it…

Sneak Peek at our URL Shortener using Flask

For a project walkthrough video visit – https://youtu.be/LwzsE8Vv-1Y

URL Shortener using Flask

Install required libraries

pip install flask hashids

Code Files For our URL Shortener

Our Project majorly consists of the following 3 code files:

  • app.py
  • index.html
  • stats.html

app.py

# URL Shortener using Flask

import sqlite3
from hashids import Hashids
from flask import Flask, render_template, request, flash, redirect, url_for

app = Flask(__name__)
app.config['SECRET_KEY'] = 'this should be a secret random string'


connection = sqlite3.connect('database.db')

c = connection.cursor()

c.execute('''CREATE TABLE IF NOT EXISTS urls(
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            created TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
            original_url TEXT NOT NULL,
            clicks INTEGER NOT NULL DEFAULT 0
        )''')

def get_db_connection():
    conn = sqlite3.connect('database.db')
    conn.row_factory = sqlite3.Row
    return conn


hashids = Hashids(min_length=4, salt=app.config['SECRET_KEY'])


@app.route('/', methods=('GET', 'POST'))
def index():
    conn = get_db_connection()

    if request.method == 'POST':
        url = request.form['url']

        if not url:
            flash('The URL is required!')
            return redirect(url_for('index'))

        url_data = conn.execute('INSERT INTO urls (original_url) VALUES (?)',(url,))
        conn.commit()
        conn.close()

        url_id = url_data.lastrowid
        hashid = hashids.encode(url_id)
        short_url = request.host_url + hashid

        return render_template('index.html', short_url=short_url)

    return render_template('index.html')



@app.route('/<id>')
def url_redirect(id):
    conn = get_db_connection()

    original_id = hashids.decode(id)
    if original_id:
        original_id = original_id[0]
        url_data = conn.execute('SELECT original_url, clicks FROM urls WHERE id = (?)', (original_id,)).fetchone()
        original_url = url_data['original_url']
        clicks = url_data['clicks']

        conn.execute('UPDATE urls SET clicks = ? WHERE id = ?',(clicks+1, original_id))
        conn.commit()
        conn.close()
        return redirect(original_url)
    else:
        flash('Invalid URL')
        return redirect(url_for('index'))



@app.route('/stats')
def stats():
    conn = get_db_connection()
    db_urls = conn.execute('SELECT id, created, original_url, clicks FROM urls').fetchall()
    conn.close()

    urls = []
    for url in db_urls:
        url = dict(url)
        url['short_url'] = request.host_url + hashids.encode(url['id'])
        urls.append(url)

    return render_template('stats.html', urls=urls)

index.html

<!doctype html>
<html lang="en">

<head>
    <!-- Required meta tags -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">

    <!-- Bootstrap CSS -->
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css"
        integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">

    <title>Welcome to FlaskShortener</title>
</head>

<body>
    <nav class="navbar navbar-expand-md navbar-light bg-light">
        <a class="navbar-brand" href="{{ url_for('index')}}">FlaskTodo</a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav"
            aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon"></span>
        </button>
        <div class="collapse navbar-collapse" id="navbarNav">
            <ul class="navbar-nav">
                <li class="nav-item active">
                    <a class="nav-link" href="#">About</a>
                </li>

                <li class="nav-item active">
                    <a class="nav-link" href="{{ url_for('stats')}}">Stats</a>
                </li>
            </ul>
        </div>
    </nav>
    <div class="container">
        {% for message in get_flashed_messages() %}
        <div class="alert alert-danger">{{ message }}</div>
        {% endfor %}

        <h1>Welcome to FlaskShortener</h1>
        <form method="post">
            <div class="form-group">
                <label for="url">URL</label>
                <input type="text" name="url" placeholder="URL to shorten" class="form-control"
                    value="{{ request.form['url'] }}" autofocus></input>
            </div>

            <div class="form-group">
                <button type="submit" class="btn btn-primary">Submit</button>
            </div>
        </form>

        {% if short_url %}
        <hr>
        <span>{{ short_url }}</span><br>
        {% endif %}

    </div>



    <!-- Optional JavaScript -->
    <!-- jQuery first, then Popper.js, then Bootstrap JS -->
    <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"
        integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo"
        crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js"
        integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1"
        crossorigin="anonymous"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"
        integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM"
        crossorigin="anonymous"></script>
</body>

</html>

stats.html

<!doctype html>
<html lang="en">

<head>
    <!-- Required meta tags -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">

    <!-- Bootstrap CSS -->
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css"
        integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">

    <title>Welcome to FlaskShortener</title>
</head>

<body>
    <nav class="navbar navbar-expand-md navbar-light bg-light">
        <a class="navbar-brand" href="{{ url_for('index')}}">FlaskTodo</a>
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav"
            aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon"></span>
        </button>
        <div class="collapse navbar-collapse" id="navbarNav">
            <ul class="navbar-nav">
                <li class="nav-item active">
                    <a class="nav-link" href="#">About</a>
                </li>

                <li class="nav-item active">
                    <a class="nav-link" href="{{ url_for('stats')}}">Stats</a>
                </li>
            </ul>
        </div>
    </nav>
    <h1>{% block title %} FlaskShortener Statistics {% endblock %}</h1>
    <table class="table">
        <thead>
            <tr>
                <th scope="col">#</th>
                <th scope="col">Short</th>
                <th scope="col">Original</th>
                <th scope="col">Clicks</th>
                <th scope="col">Creation Date</th>
            </tr>
        </thead>
        <tbody>
            {% for url in urls %}
            <tr>
                <th scope="row">{{ url['id'] }}</th>
                <td>{{ url['short_url'] }}</td>
                <td>{{ url['original_url'] }}</td>
                <td>{{ url['clicks'] }}</td>
                <td>{{ url['created'] }}</td>
            </tr>
            {% endfor %}
        </tbody>
    </table>

    <!-- Optional JavaScript -->
    <!-- jQuery first, then Popper.js, then Bootstrap JS -->
    <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"
        integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo"
        crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js"
        integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1"
        crossorigin="anonymous"></script>
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"
        integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM"
        crossorigin="anonymous"></script>
</body>

</html>

Our Final Output

Refer to this article for deploying it online – How to Deploy a Flask app online using Pythonanywhere

And this is how you can create a URL Shortener using Flask…

So this is all for this blog folks. Thanks for reading it and I hope you are taking something with you after reading this and till the next time …

Read my last blog – Create an API in Flask and deploy it online

Check out my other machine learning projectsdeep learning projectscomputer vision projectsNLP projects, and Flask projects at machinelearningprojects.net.

Leave a Comment

Your email address will not be published. Required fields are marked *