55 lines
1.8 KiB
Python
55 lines
1.8 KiB
Python
|
from datetime import datetime, timedelta
|
||
|
|
from json import dump, load
|
||
|
|
from pathlib import Path
|
||
|
|
from typing import Any, Callable, Generic, TypeVar, TypedDict
|
||
|
|
from requests import RequestException, get
|
||
|
|
|
||
|
|
|
||
|
|
T = TypeVar('T')
|
||
|
|
|
||
|
|
class Cached(TypedDict, Generic[T]):
|
||
|
|
loaded: int
|
||
|
|
data: T
|
||
|
|
|
||
|
|
|
||
|
|
def get_resource(url: str):
|
||
|
|
with get(url) as request:
|
||
|
|
request.raise_for_status()
|
||
|
|
return request.json()
|
||
|
|
|
||
|
|
|
||
|
|
def load_cached(url: str, cache_file: Path, loader: Callable[[str], T] = get_resource, max_age: timedelta = timedelta(hours=1), reload: bool = False, encoding: str = "utf-8") -> T:
|
||
|
|
if reload:
|
||
|
|
# print(f"Forced cache reload for {cache_file}!")
|
||
|
|
pass
|
||
|
|
else:
|
||
|
|
try:
|
||
|
|
with cache_file.open("r", encoding=encoding) as f:
|
||
|
|
cached = load(f)
|
||
|
|
data: T = cached["data"]
|
||
|
|
time = datetime.fromtimestamp(cached["loaded"])
|
||
|
|
cache_age = datetime.now() - time
|
||
|
|
if cache_age <= max_age:
|
||
|
|
# print(f"Loaded cache file with age {cache_age}.")
|
||
|
|
return data
|
||
|
|
# print(f"Cache is older than {max_age} and will be reloaded.")
|
||
|
|
except FileNotFoundError:
|
||
|
|
# print(f"File {cache_file} not cached, will be reloaded!")
|
||
|
|
pass
|
||
|
|
|
||
|
|
data = loader(url)
|
||
|
|
data_dict_tmp: Any = data
|
||
|
|
data_dict: dict[str, Any] = data_dict_tmp
|
||
|
|
status: None | str = data_dict.get("status", None)
|
||
|
|
if status is not None and status.lower() == "error":
|
||
|
|
raise RequestException(data_dict.get("message", "No error message!"))
|
||
|
|
|
||
|
|
# Save to cache
|
||
|
|
cached: Cached[T] = {"data": data, "loaded": int(
|
||
|
|
datetime.now().timestamp())}
|
||
|
|
cache_file.parent.mkdir(parents=True, exist_ok=True)
|
||
|
|
with cache_file.open("w", encoding=encoding) as f:
|
||
|
|
dump(cached, f)
|
||
|
|
|
||
|
|
return data
|