Files
snippets/pickle_cache.py
2024-03-14 22:17:41 +01:00

41 lines
1.6 KiB
Python

def pickle_cache(mode="auto"):
def pc_decorator(func):
def pc_wrapper(*args, **kwargs):
cache_fp = Path(PROXY_DIR, f"{func.__name__}.pickle")
today = dt.date.today()
if cache_fp.exists():
statinfo = cache_fp.stat()
# (st_mode, st_ino, st_dev, st_nlink, st_uid, st_gid, st_size, st_atime, st_mtime, st_ctime) = statinfo
(_, _, _, _, _, _, _, _, st_mtime, _) = statinfo
mdate = dt.datetime.fromtimestamp(st_mtime).date()
else:
mdate = None
if mode == "auto":
if cache_fp.exists() and mdate == today:
action = "cached"
else:
action = "query"
else:
action = mode
if action == "cached" :
LOG.info(f"{func.__name__}: loading cached data...")
with cache_fp.open("rb") as fh:
rc = pickle.load(fh)
elif action == "query":
LOG.info(f"{func.__name__}: database access...")
rc = func(*args, **kwargs)
if cache_fp.exists() and mdate != today and Path(PROXY_DIR, "Archive").exists():
archive_fp = Path(PROXY_DIR, "Archive", f"{func.__name__}-{mdate:%Y%m%d}.pickle")
shutil.copy(cache_fp, archive_fp)
with cache_fp.open("wb") as fh:
pickle.dump(rc, fh)
else:
LOG.error(f"{func.__name__}: mode {action} unknown")
return rc
return pc_wrapper
return pc_decorator