Name: How to Create a Simple URL Shortener Tool with Python
Rating: 2.8 (4239 reviews)
Author: zerobytecode

A URL shortener tool allows users to take a long URL and convert it into a shorter, more manageable link. We can build a simple version of this tool using Python and Flask, a lightweight web framework.

Prerequisites

Before starting, ensure you have the following:

Python installed on your system (Python 3.6+ is recommended).
Flask installed. You can install Flask using pip.

Step 1: Setting Up Your Environment

First, you need to create a virtual environment and install Flask. Open your terminal and run the following commands:

# Create a virtual environment
python -m venv myenv

# Activate the virtual environment
# On Windows
myenv\Scripts\activate
# On macOS/Linux
source myenv/bin/activate

# Install Flask
pip install Flask

Step 2: Writing the Code

Create a directory for your project, e.g., url_shortener, and inside it, create a Python file called app.py. We'll break down the code into sections.

Importing Required Libraries

from flask import Flask, request, redirect, url_for
import string
import random

Setting Up Flask App and Database

We'll use a simple in-memory dictionary to store the URL mappings. For a more robust solution, you might use a database like SQLite or PostgreSQL.

app = Flask(__name__)
url_mapping = {}

Function to Generate Short URLs

We'll create a function that generates a short URL key.

def generate_short_url():
    characters = string.ascii_letters + string.digits
    short_url = ''.join(random.choice(characters) for _ in range(6))
    return short_url

Route to Handle URL Shortening

This route will take a long URL from the user and return a shortened version.

@app.route('/shorten', methods=['POST'])
def shorten_url():
    original_url = request.form['url']
    short_url = generate_short_url()
    url_mapping[short_url] = original_url
    return f'Shortened URL: {request.host_url}{short_url}'

Route to Redirect Short URLs

This route will redirect users from the short URL to the original long URL.

@app.route('/<short_url>')
def redirect_url(short_url):
    original_url = url_mapping.get(short_url)
    if original_url:
        return redirect(original_url)
    else:
        return 'URL not found', 404

Main Function to Run the App

if __name__ == "__main__":
    app.run(debug=True)

Step 3: Running the Tool

Save your app.py file and run it from the terminal:

python app.py

The Flask development server will start, and you can access the URL shortener tool by navigating to http://127.0.0.1:5000 in your web browser.

Step 4: Testing the Tool

To shorten a URL, you can use a tool like curl or a simple HTML form. Here's a basic HTML form for testing:

<!DOCTYPE html>
<html>
<head>
    <title>URL Shortener</title>
</head>
<body>
    <form action="http://127.0.0.1:5000/shorten" method="post">
        <label for="url">Enter URL to shorten:</label>
        <input type="text" id="url" name="url">
        <input type="submit" value="Shorten">
    </form>
</body>
</html>

Save this HTML code as index.html and open it in your web browser. Enter a URL to shorten and submit the form. You should see a shortened URL that you can use to test the redirection functionality.

Conclusion

By following these steps, you can create a simple URL shortener tool using Python and Flask.

This tool can be further enhanced with additional features such as user authentication, analytics, and a database for storing URL mappings persistently.

Alternatively you can also read how to create a simple URL Shortener tool using Python.

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