What are some advanced examples of decorators in Django?

What are some advanced examples of decorators in Django?

In Django, decorators are a powerful way to modify the behavior of views. Here are a few advanced examples:

1. Custom Permission Decorator: You can create a decorator that checks if a user has specific permissions before allowing access to a view.

2. Rate Limiting Decorator: This decorator can limit the number of requests a user can make to a view within a certain timeframe.

3. Caching Decorator: Use a decorator to cache the output of a view for a specified duration, improving performance.

Would you like to see code examples for any of these?

Yes, please show me the custom permission decorator.

Sure! Here's a simple example of a custom permission decorator:

from django.http import HttpResponseForbidden
from functools import wraps

def user_has_permission(permission):
    def decorator(view_func):
        @wraps(view_func)
        def _wrapped_view(request, *args, **kwargs):
            if request.user.has_perm(permission):
                return view_func(request, *args, **kwargs)
            return HttpResponseForbidden('You do not have permission to access this page.')
        return _wrapped_view
    return decorator

# Usage:
@user_has_permission('app_name.can_view')
def my_view(request):
    # Your view logic here

This decorator checks if the user has the specified permission before allowing access to the view.

That's great! Can you give me an example of the rate limiting decorator?

Absolutely! Here's a basic example of a rate limiting decorator using Django's cache framework:

from django.core.cache import cache
from django.http import HttpResponseTooManyRequests
from functools import wraps

def rate_limit(limit, period):
    def decorator(view_func):
        @wraps(view_func)
        def _wrapped_view(request, *args, **kwargs):
            key = f'rate_limit_{request.user.id}'
            requests = cache.get(key, 0)
            if requests >= limit:
                return HttpResponseTooManyRequests('Too many requests, please try again later.')
            cache.set(key, requests + 1, timeout=period)
            return view_func(request, *args, **kwargs)
        return _wrapped_view
    return decorator

# Usage:
@rate_limit(limit=5, period=60)
def my_view(request):
    # Your view logic here

This decorator allows a user to make a limited number of requests within a specified time period.