70 lines
1.8 KiB
Python
70 lines
1.8 KiB
Python
from typing import Any
|
|
import base64
|
|
import struct
|
|
import binascii
|
|
import json
|
|
|
|
|
|
def to_bytes(x: Any, charset: str = "utf-8", errors: str = "strict") -> bytes:
|
|
if isinstance(x, bytes):
|
|
return x
|
|
if isinstance(x, str):
|
|
return x.encode(charset, errors)
|
|
if isinstance(x, (int, float)):
|
|
return str(x).encode(charset, errors)
|
|
return bytes(x)
|
|
|
|
|
|
def to_str(x: bytes | str, charset: str = "utf-8") -> str:
|
|
if isinstance(x, bytes):
|
|
return x.decode(charset)
|
|
return x
|
|
|
|
|
|
def urlsafe_b64decode(s: bytes) -> bytes:
|
|
if b"+" in s or b"/" in s or b"=" in s:
|
|
raise binascii.Error
|
|
|
|
pad = -len(s) % 4
|
|
if pad == 3:
|
|
raise binascii.Error
|
|
|
|
safe_ending = (b"AEIMQUYcgkosw048", b"AQgw")
|
|
if pad and s[-1] not in safe_ending[pad - 1]:
|
|
raise binascii.Error
|
|
|
|
s += b"=" * pad
|
|
return base64.b64decode(s, b"-_", validate=True)
|
|
|
|
|
|
def urlsafe_b64encode(s: bytes) -> bytes:
|
|
return base64.urlsafe_b64encode(s).rstrip(b"=")
|
|
|
|
|
|
def base64_to_int(s: str) -> int:
|
|
data = urlsafe_b64decode(to_bytes(s))
|
|
buf = struct.unpack("%sB" % len(data), data)
|
|
return int("".join(["%02x" % byte for byte in buf]), 16)
|
|
|
|
|
|
def int_to_base64(num: int, byte_count: int | None = None) -> str:
|
|
if num < 0:
|
|
raise ValueError("Must be a positive integer")
|
|
|
|
if byte_count is None:
|
|
byte_count = (num.bit_length() + 7) // 8
|
|
elif num.bit_length() > byte_count * 8:
|
|
raise ValueError("Number too large for byte count")
|
|
|
|
s = num.to_bytes(byte_count, "big", signed=False)
|
|
return urlsafe_b64encode(s).decode("utf-8", "strict")
|
|
|
|
|
|
def json_b64encode(data: dict[str, Any]) -> bytes:
|
|
text = json.dumps(data, ensure_ascii=True, separators=(",", ":"))
|
|
return urlsafe_b64encode(to_bytes(text, "ascii"))
|
|
|
|
|
|
def json_b64decode(text: bytes) -> Any:
|
|
return json.loads(urlsafe_b64decode(text))
|