blob: 1e28969d2d6819b7dcc289a2c501705f96d113f2 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
import base64
import string
import struct
from ._compat import text_type
from .exc import BadData
def want_bytes(s, encoding="utf-8", errors="strict"):
if isinstance(s, text_type):
s = s.encode(encoding, errors)
return s
def base64_encode(string):
"""Base64 encode a string of bytes or text. The resulting bytes are
safe to use in URLs.
"""
string = want_bytes(string)
return base64.urlsafe_b64encode(string).rstrip(b"=")
def base64_decode(string):
"""Base64 decode a URL-safe string of bytes or text. The result is
bytes.
"""
string = want_bytes(string, encoding="ascii", errors="ignore")
string += b"=" * (-len(string) % 4)
try:
return base64.urlsafe_b64decode(string)
except (TypeError, ValueError):
raise BadData("Invalid base64-encoded data")
# The alphabet used by base64.urlsafe_*
_base64_alphabet = (string.ascii_letters + string.digits + "-_=").encode("ascii")
_int64_struct = struct.Struct(">Q")
_int_to_bytes = _int64_struct.pack
_bytes_to_int = _int64_struct.unpack
def int_to_bytes(num):
return _int_to_bytes(num).lstrip(b"\x00")
def bytes_to_int(bytestr):
return _bytes_to_int(bytestr.rjust(8, b"\x00"))[0]
|
