Validation Features

Types and ranges

schema = {
    "name": v.str().range(3, 20),
    "score": v.float().range(0.0, 100.0),
    "enabled": v.bool(),
}

Coercion

schema = {
    "port": v.int().coerce(),
    "enabled": v.bool().coerce(),
}

Conditional fields

schema = {
    "is_admin": v.bool(),
    "admin_key": v.str().when(lambda data: data.get("is_admin") is True),
}

Custom validation

def normalize(value: str) -> str:
    value = value.strip()
    if not value:
        raise ValueError("empty value")
    return value

schema = {"name": v.str().custom(normalize)}