SREF Reader

A Python library that reads and validates SREF (Structured Recipe Exchange Format) recipe JSON, .sref packages, and .srefbundle bundles, and converts amounts between registered units exactly. It does not write recipes; SREF Writer is the separate library for that.

Install

Python 3.10 or later. From the repository root:

python3 -m venv .venv
. .venv/bin/activate
python3 -m pip install .

The only runtime dependency is jsonschema. The SREF schemas and unit registry ship inside the distribution, so no specification checkout is needed at runtime.

Example

import json
import sref_reader

recipe = sref_reader.read_recipe(
    json.dumps(
        {
            "sref": {"version": "0.4.0", "unit_registry": "0.2.0"},
            "id": "tea",
            "title": "Tea",
            "instruction_sections": [
                {
                    "id": "method",
                    "steps": [{"id": "steep", "text": "Steep the tea, then strain."}],
                }
            ],
        }
    ).encode("utf-8")
)
print(recipe["title"])

Documentation

• Usage: reading, diagnostics, unit conversion, streaming bundles, and resource limits.
• Development: checks, conformance, and testing the installed distribution.

Compatibility

__version__ and pyproject.toml version this library. SUPPORTED_FORMAT (0.4.0) and SUPPORTED_REGISTRY (0.2.0) name the SREF and unit-registry versions it implements. The three numbers are independent.

The vendored SREF snapshot is loaded through importlib.resources and checked against its manifest digests; altered bytes fail to load. Documents are checked against the schema and then against the semantic and archive rules the schema cannot express. A document from a compatible newer SREF version keeps its unrecognized members and extensions, and no meaning is invented for them.

Contributing

Every commit carries a Developer Certificate of Origin sign-off, created with git commit -s:

Signed-off-by: Your Name <your-email@example.com>

The sign-off certifies the statement at https://developercertificate.org/, and CI rejects a commit whose sign-off does not name its author.

Licence

MIT, in LICENSE.txt. The vendored schemas and registry data keep SREF's CC0 1.0 Universal dedication.