v1.0.0 module file added to repo.

base64url.py

@@ -0,0 +1,26 @@
+"""URL-safe Base64 encoding without padding.
+
+This format uses only characters that are safe for URLs, filenames etc.
+Refer to Python's urlsafe_b64encode and base64.urlsafe_b64decode for more details.
+
+Fixes Python base64 module's faults:
+- Padding "==" is optional and not produced by b64url.enc
+- Base64 type is str (stdlib is retarded and uses bytes)
+- Otherwise identical to urlsafe_b64encode/urlsafe_b64decode
+"""
+
+from base64 import urlsafe_b64decode as _decode
+from base64 import urlsafe_b64encode as _encode
+
+__all__ = ["enc", "dec"]
+
+
+def enc(data: bytes) -> str:
+    """Base64 encode bytes to a URL-safe string without padding."""
+    return _encode(data).decode("ascii").rstrip("=")
+
+
+def dec(s: str) -> bytes:
+    """Decode URL-safe Base64 into bytes. Padding optional."""
+    # Testing whether needs padding is slower, this is the fastest way and constant time.
+    return _decode(s + "=" * (4 - (len(s) % 4)))