@login_required – Python

@login_required is a decorator commonly used in Python web frameworks like Django and Flask. It is used to restrict access to certain views or functions in an application based on whether the user is logged in or not. This decorator ensures that only authenticated users can access certain resources or perform specific actions within the application.

The @login_required decorator is often used in conjunction with user management and authentication systems to provide a secure and controlled user experience. It helps protect sensitive data and prevents unauthorized access to restricted areas of an application.

How to Use @login_required

To use the @login_required decorator in your Python application, follow these steps:

1. Import the necessary dependencies:

   from functools import wraps
   from flask import redirect, url_for
   from flask_login import current_user
   

2. Define the @login_required decorator:

   def login_required(view_func):
       @wraps(view_func)
       def wrapped_view(*args, **kwargs):
           if not current_user.is_authenticated:
               return redirect(url_for('login'))
           return view_func(*args, **kwargs)
       return wrapped_view
   

3. Apply the @login_required decorator to your views or functions that require authentication:

   @app.route('/dashboard')
   @login_required
   def dashboard():
       # Only logged-in users can access this view
       return 'Welcome to the dashboard!'
   

In the example above, the @login_required decorator checks whether the current_user object is authenticated. If the user is not authenticated, the decorator redirects them to the login page using the redirect function from Flask. If the user is authenticated, the original view or function is called, allowing access to the resource.

Markdown Code Snippet

Here is an example of how to use the @login_required decorator in Python:

from functools import wraps
from flask import redirect, url_for
from flask_login import current_user

def login_required(view_func):
   @wraps(view_func)
   def wrapped_view(*args, **kwargs):
       if not current_user.is_authenticated:
           return redirect(url_for('login'))
       return view_func(*args, **kwargs)
   return wrapped_view

@app.route('/dashboard')
@login_required
def dashboard():
   # Only logged-in users can access this view
   return 'Welcome to the dashboard!'

Remember to replace 'login' in the redirect(url_for('login')) line with the actual URL or endpoint of your login page.

By using the @login_required decorator, you can easily enforce authentication requirements in your Python web application, preventing unauthorized access and improving security.