rfc-9741-pure

Zero-dependency pure-Python RFC 9741 CDDL Additional Control Operators.

"Validate CBOR/COSE/CWT tokens using .b64u, .b64c, .hex, .b45, .base10, .printf, and .json — no cddl or cbor2 required."

Quick Start

pip install git+https://github.com/prasad-a-abhishek/rfc-9741-pure.git

from rfc9741pure import validate_b64u, validate_hex, validate_base10, validate_printf, validate_json

# .b64u — Base64url (RFC 4648 §5)
assert validate_b64u("YWJj", b"abc") == True

# .hex — Base16 / hex (RFC 4648 §8)
assert validate_hex("deadbeef", b"\xde\xad\xbe\xef") == True

# .base10 — decimal integer text
assert validate_base10("42", 42) == True
assert validate_base10("042", 42) == False  # no leading zeros

# .printf — Printf-style formatting
assert validate_printf("0x0013", ["0x%04x", 19]) == True

# .json — JSON text → Python object
assert validate_json('{"a":1}', {"a": 1}) == True

⚡ Performance & Benchmarks

Benchmark: rfc9741pure.encode_b64u vs base64.urlsafe_b64encode — 5 iterations × 5 workload sizes (10 KB – 1 MB).

Run locally: python3 benchmarks/run_benchmark.py

Why rfc-9741-pure?

The cddl and cbor2 packages implement RFC 8610 CDDL but bundle RFC 9741 operators into large dependency trees with C extensions. rfc-9741-pure gives you exactly the RFC 9741 control operators — .b64u, .b64c, .hex, .b45, .base10, .printf, .json — as a single-file pure-Python library with zero external dependencies.

Trade-offs vs competitors:

• cddl / cbor2: full CDDL/CBOR stack but require compiled extensions and pull in many dependencies.
• rfc-9741-pure: isolated RFC 9741 operators only, pure stdlib, no installation friction.

Key Features & Complete API Reference

Library API

from rfc9741pure import (
    # Base64url (.b64u) — RFC 4648 §5, no padding
    decode_b64u, encode_b64u, validate_b64u,
    # Base64 classic (.b64c) — RFC 4648 §4, with padding
    decode_b64c, encode_b64c, validate_b64c,
    # Base16 / hex (.hex) — RFC 4648 §8
    decode_hex, encode_hex, validate_hex, validate_hexlc, validate_hexuc,
    # Base45 (.b45) — RFC 9285
    decode_b45, encode_b45, validate_b45,
    # Decimal integer (.base10)
    decode_base10, encode_base10, validate_base10,
    # Printf-style formatting (.printf)
    decode_printf, format_printf, validate_printf,
    # JSON text (.json)
    decode_json, encode_json, validate_json,
)

All functions are TOTAL — they never raise on arbitrary input; invalid inputs return structured error results.

CLI

rfc9741pure --help
rfc9741pure validate <file>
rfc9741pure encode b64u "Hello"
rfc9741pure encode hex "Hello"
rfc9741pure decode b64u "SGVsbG8"

Test Coverage

261 tests covering:

• Happy path (valid encodes/decodes)
• Error paths (malformed input, padding errors)
• Edge cases (empty input, large input, unicode)
• Boundary conditions (leading zeros, negative zero)
• CLI + library parity
• Property-based validation

License

MIT License — Copyright (c) 2025 Abhishek Prasad. See LICENSE file.