keyvalues3

KeyValues3 is a Valve developed data format. It is similar in structure to JSON, but supports binary encodings, versioning, and data annotations. The text syntax also has some minor ergonomic improvements (support for single- and multi-line comments, trailing commas, and multi-line strings.)

Usage

import keyvalues3 as kv3
bt_config = kv3.read("tests/documents/bt_config.kv3")

>>> bt_config.keys()
dict_keys(['default', 'low', 'fair', 'normal', 'tough', 'hard', 'very_hard', 'expert', 'elite'])

>>> bt_config["elite"]["reaction_time"]
0.12

# The root value is most of the time a dict
>>> type(bt_config.value)
<class 'dict'>

>>> bt_config.original_encoding
Encoding(name='text', version=UUID('e21c7f3c-8a33-41c5-9977-a76d3a32aa0d'))

>>> bt_config.format
Format(name='generic', version=UUID('7412167c-06e9-4698-aff2-e63eb59037e7'))

# To write it back
>>> kv3.write(bt_config, "tests/documents/bt_config.kv3", use_original_encoding=True)

# Write to a stream
>>> import sys
>>> kv3.write({"key": [1,2,3]}, sys.stdout)
<!-- kv3 encoding:text:version{e21c7f3c-8a33-41c5-9977-a76d3a32aa0d} format:generic:version{7412167c-06e9-4698-aff2-e63eb59037e7} -->
{
        key = [1, 2, 3]
}

Install

pip install keyvalues3

Supported encodings

Encoding 👩‍💻	Read 📖	Write ✍️
Text UTF-8	Yes ✔️	Yes ✔️
Text UTF-8 Headerless	Yes ✔️	Yes ✔️
Binary (VKV) Uncompressed	Yes ✔️	Yes ✔️
Binary (VKV) LZ4	Yes ✔️	Yes ✔️
Binary (3VK) V1	Yes ✔️	No ⛔
Binary (3VK) V2	Yes ✔️	No ⛔
Binary (3VK) V3	Yes ✔️	No ⛔
Binary (3VK) V4	Yes ✔️	No ⛔
Binary (3VK) V5	Yes ✔️	No ⛔

Using dataclasses

Dataclasses (marked with @dataclass) are also supported for serialization (uses asdict())

@dataclass
class RenderMeshFile(_Node):  # _Node defines _class, name, notes, and children (+ helper methods)
    filename: resourcepath = ""
    import_translation: list[float] = field(default_factory=lambda: [0, 0, 0])
    import_rotation: list[float] = field(default_factory=lambda: [0, 0, 0])
    import_scale: float = 1.0
    align_origin_x_type: str = "None"
    align_origin_y_type: str = "None"
    align_origin_z_type: str = "None"
    parent_bone: namelink = ""
    import_filter: dict = field(
        default_factory=lambda:dict(
            exclude_by_default = False,
            exception_list = [  ]
        )
    )

You can find more ModelDoc dataclasses here.

Developing

python --version Ensure you're using Python 3.12 or greater.
python -m pip install .
python -m pip install pytest I don't know why this is needed
python -m pytest

Credits

Valve Corporation® for making KeyValues3.
ValveResourceFormat for the legacy binary reader reference.
SourceIO by REDxEYE for new binary reader code.