cached decorator

The cached decorator is designed to cache the result of a function and retrieve the cached result for subsequent calls, based on a specified key. It also supports setting a time-to-live (TTL) for the cached values.

The returned function value should be picklable, i.e. a pydantic's BaseModel subclasses are picklable, but a Django's Response is not. There is an issue present to implement an ability to provide custom encoders/decoders to extend the possible applications.

It detects the type of function that it is being applied to automatically using a compatible cache client for it (sync or async).

TYPE CHECKING: Currently there is no way (or we haven't found one) to correctly type annotate a decorator so that you won't have to ignore or cast the results of a function the decorator is being applied to. In order to use specific decorator to match your runtime you can import the desired one with:

from py_cachify.sync import sync_cached
# OR for async
from py_cachify.asyncio import async_cached

Parameters

Param name	Param type	Description	Default
key	str	The unique identifier used to determine whether the function has already been executed. The key can be a string containing placeholders to be formatted with function arguments.
ttl	int, None, optional	Time-to-live for the cached value in seconds. If None, the value is cached indefinitely.	None

Usage

from py_cachify import cached

@cached(key='example_key', ttl=60)
def expensive_function(x):
    print('Executing expensive operation...')
    return x ** 2


@cached(key='example_async_function-{arg_a}-{arg_b}')
def async_expensive_function(arg_a: int, arg_b: int) -> int:
    return arg_a + arg_b

The cached decorator is applied to a function, ensuring that the decorated function's result is cached for subsequent calls.

It checks the cache for the result using the specified key. If the result is found, it is returned; otherwise, the original function is executed, and the result is stored in the cache.

The ttl parameter allows setting a time-to-live for the cached value. If provided (in the first example), the cached value will be automatically invalidated after the specified time.