Decorators

A handful of general-purpose decorators.

djutils.decorators.cached_for_model(cache_timeout=300)

Model method decorator that caches the return value for the given time. Similar to memoize() but uses the cache and is designed for use on model instances

Usage:

class MyModel(models.Model):
    ...

    @cached_for_model(60)
    def get_expensive_data(self, some_arg):
        # do expensive calculations here
        return data

djutils.decorators.throttle(methods_or_func, limit=3, duration=900)

Throttle the given function, returning 403s if limit exceeded

Example:

# limit to 5 POST or PUT requests per 5 minutes:

@throttle(['POST', 'PUT'], 5, 300)
def my_view(request, ...):
    # do some stuff


# limit to 3 POST requests per 15 minutes:

@throttle
def my_other_view(request, ...):
    # do some other stuff

djutils.decorators.memoize(func)

avoid repeating the calculation of results for previously-processed inputs

Example:

@memoize
def calculate_big_number(input1, input2):
    # do some complicated stuff
    return result

djutils.decorators.async(func)

Execute the function asynchronously in a separate thread

Example:

@async
def send_email(to, subj, body):
    # this will be executed in a separate thread
    mail([to], subj, body)