Unsupported json feature in xgrammar

[gryffindor-rr]

I'm also trying to use vLLM to support guided decoding of my request. currently it's default guided backend set to xgrammar (which I thought having better performance). however, in my case, it falls back to 'outlines' because it detected some json feature are not supported by xgrammar. see https://github.com/vllm-project/vllm/blob/e92694b6fe264a85371317295bca6643508034ef/vllm/model_executor/guided_decoding/utils.py#L6

I'm wondering if this limitation still exists? my target json schema is like
{
"type": "object",
"additionalProperties": false,
"properties": {
"POINT": {
"oneOf": [
{
"type": "integer",
"minimum": 0,
"maximum": 500
},
{
"$ref": "#/$defs/Location",
}
]
}
}
"$defs": {
"Location": {
"type": "array",
"items": {
"type": "integer",
"minimum": 0,
"maximum": 1000
},
"minItems": 2,
"maxItems": 2
}
}
}

I'm wondering why xgrammar did not support array and integer min and max range?

[Ubospica]

Hi @gryffindor-rr, thanks for asking about that. Currently, the min and max integer range is supported (we are enhancing it in #182 to better support negative integer range). The num of items is still ongoing. Please stay tuned!

[Ubospica]

We will sync with vLLM team to enable more features of json schema with XGrammar backend.

[russellb]

We will sync with vLLM team to enable more features of json schema with XGrammar backend.

I work on vLLM and try to watch the activity on this repo so I catch updates. Let me know if something is working that we haven't enabled! I'm about to turn regex on since it seems like we should be good in 0.1.12.