27 lines
924 B
Python
27 lines
924 B
Python
"""URL-safe Base64 encoding without padding.
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This format uses only characters that are safe for URLs, filenames etc.
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Refer to Python's urlsafe_b64encode and base64.urlsafe_b64decode for more details.
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Fixes Python base64 module's faults:
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- Padding "==" is optional and not produced by b64url.enc
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- Base64 type is str (stdlib is retarded and uses bytes)
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- Otherwise identical to urlsafe_b64encode/urlsafe_b64decode
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"""
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from base64 import urlsafe_b64decode as _decode
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from base64 import urlsafe_b64encode as _encode
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__all__ = ["enc", "dec"]
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def enc(data: bytes) -> str:
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"""Base64 encode bytes to a URL-safe string without padding."""
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return _encode(data).decode("ascii").rstrip("=")
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def dec(s: str) -> bytes:
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"""Decode URL-safe Base64 into bytes. Padding optional."""
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# Testing whether needs padding is slower, this is the fastest way and constant time.
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return _decode(s + "=" * (4 - (len(s) % 4)))
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