@game-gpt/von-schema

Validation for applications that store structured documents in VON.

VON defines a portable value format; it does not decide which fields your application requires. @game-gpt/von-schema fills that deliberate gap with a small, JSON Schema-inspired vocabulary designed around VON V1 values.

Validate a document

import {parse} from "@game-gpt/von";
import {validate, type VonSchema} from "@game-gpt/von-schema";

const schema: VonSchema = {
    type: "object",
    required: ["format", "version", "name"],
    additionalProperties: false,
    properties: {
        format: {type: "string", const: "app.config"},
        version: {type: "integer", minimum: 1},
        name: {type: "string", minLength: 1},
    },
};

const result = validate(
    parse(`{ format: "app.config", version: 1, name: "atlas" }`),
    schema,
);

if (!result.valid) {
    for (const error of result.errors) {
        console.error(`${error.path}: ${error.message}`);
    }
}

validate returns { valid, errors } instead of throwing for ordinary validation failures. Each error carries a data path, readable message, and the schema keyword that failed.

Supported vocabulary

• type, const, and enum;
• integer minimum and maximum;
• string length and pattern;
• array items, length, and uniqueness;
• object properties, required keys, property counts, and additionalProperties;
• anyOf, oneOf, allOf, and not;
• local definitions through definitions and $defs.

The VON type vocabulary uses integer, not JSON Schema's broader number, because floating-point values do not exist in VON V1. This package is JSON Schema-inspired rather than a claim of complete draft conformance; treat the exported VonSchema type and validation tests as the implemented surface.

Develop

pnpm --filter @game-gpt/von-schema test
pnpm --filter @game-gpt/von-schema typecheck
pnpm --filter @game-gpt/von-schema build

Run these commands from the repository root. Licensed under MPL-2.0. Start with @game-gpt/von when you need parsing or serialization.