def get_quremo(a, b):
"""Memcache or DataStore interaction implementation
with aim to avoid server calculations overload"""
a_key = a + '&' + b # an unique key for each pair
# looking for MemCache value firstly:
cached_result = memcache.get(key=a_key)
if cached_result is None:
# looking for persistent cached value:
q = Result.query(Result.a_key == a_key)
if q.get(): # the values are there
calc_val = tuple(q.fetch(1)[-1].a_value)
memcache.add(key=a_key, value=calc_val, time=60)
logging.info("Data was restored out from ndb")
else: # values are completely new
calc_val = quremo(a, b)
memcache.add(key=a_key, value=calc_val, time=60)
R = Result()
R.a_key, R.a_value = a_key, calc_val
R.put()
logging.info("Data is new and was cached successfully")
else:
calc_val = cached_result
logging.info("Data was retrieved out from MemCache")
return calc_val
