No depenencies, no external services functional cache.
Only relies on sqlite3 from the standard python library plus hashlib.sha1 and json.dumps also from standard library.
Note: Most of the limits are due to sqlite. There are other libraries who can relief you from these limits. Also this is probabily not usable as a 'real' cache because there is no 'expiry' option. That is why it is a functional cache:
f(x) => y, where function f always gives output y given input x.
Therefore it is usable for expensive and/or recursive functions.
Example for a recursive factorial function:
from functional_cache import FunctionalCache
f = FunctionalCache("factorial.db")
@f.cache
def factorial(n: int) -> str:
"""factorial function that returns the answer in a string.
This so sqlite can save the large integers.
"""
if n < 2:
return "1"
else:
return str(n*int(factorial(n-1)))
def build_up_factorial(n):
print("This will build a factorial database until {n}!".format(n=n))
for i in range(20, n, 20):
print("now at {i}".format(i=i), end="\r")
factorial(i)
n = 900
build_up_factorial(n)
print("{}! = {}".format(n, factorial(900)))
