add b2a_base64url

2024-06-03 11:03:01 -04:00 · 2024-06-03 11:03:01 -04:00 · bc601ae1ec
commit bc601ae1ec
parent 34328a0d30
1 changed files with 4 additions and 0 deletions
--- a/shared/utils.py
+++ b/shared/utils.py
@ -178,6 +178,10 @@ class Base64Writer:
            assert tmp[-2:-1] != b'=', tmp
            self.fd.write(tmp[:-1])

+def b2a_base64url(s):
+    # see <https://datatracker.ietf.org/doc/html/rfc4648#section-5>
+    return b2a_base64(s).rstrip(b'=\n').replace(b'+', b'-').replace(b'/', b'_')
+
 def swab32(n):
    # endian swap: 32 bits
    return ustruct.unpack('>I', ustruct.pack('<I', n))[0]