Functools

Why

If you want to _cache the calls to a specific method or function you could use the python functools._cache decorator. If this has not enough configuration options for your taste, or you work with arguments which are not hashable this _ cache decorator could be useful.

Advantages

• Works with non hashable objects
• Set expiry after time
• Set expiry after a schedule
• Set maximal _cache size per method
• Works with sync and async functions
• Properly tested

Usage

Cache

Use a cache which expires after a certain amount of time:

from pycache import cache


# The format for schedule_type is <hh:mm:ss>
# This _cache would expire every 10 seconds
@cache(expires_at="*:*:10")
def please_cache():
    pass


# This _cache would expire every 5 minutes and 10 seconds
@cache(expires_every="*:5:10")
def please_cache():
    pass

Use a _cache which expires every time at a certain time (A bit like a cron job).

from pycache import cache


# The format for _schedule_str is <hh:mm:ss>
# This _cache would expire every day at 15:10:05
@cache(expires_at="15:10:05")
def please_cache():
    pass


# This _cache would expire every hour 8 minutes after a full hour
@cache(expires_at="*:08:00")
def please_cache():
    pass

Limit the number of _cache entries

from pycache import cache


# This would result in only one _cache entry
@cache(expires_every="*:*:10", max_cache_size=1)
def please_cache(data: str):
    pass


# Gets placed in _cache
please_cache("hello")
# Gets called from _cache
please_cache("hello")

# Gets placed in _cache and "hello" gets removed
please_cache("world")

# Is not found in _cache, because "world" is the only _cache entry, 
# because the _cache size is one
please_cache("hello")

Schedule

from pycache import schedule, add_schedule, ScheduleSubscription
import asyncio


# Gets called every 10 seconds
@schedule(call_every="*:*:10")
def schedule_me():
    pass


# Gets called every at 10 am
@schedule(call_every="10:00:00")
def schedule_me():
    pass


# Gets called 3 times
@schedule(call_every="10:00:00", stop_after=3)
def schedule_me():
    pass


# Call with args and keyword args
@schedule(call_every="10:00:00", args=(3,), kwargs={"hello": "world"})
def schedule_me(three: int, hello: str):
    pass


# Pass an event loop
@schedule(call_every="10:00:00", event_loop=your_event_loop)
async def schedule_me():
    pass


def schedule_programmatically():
    pass


# Call this every five seconds
schedule_subscription: ScheduleSubscription = add_schedule(schedule_programmatically, call_every="*:*:5")

# Stop the schedule call
schedule_subscription.stop()

# Start the schedule again
schedule_subscription.start()