Support for custom SentenceTransformer models

Model description

I have a custom SentenceTransformer model that is a custom class (And also quite nested), so on the top level the modules.json file look like

[
  {
    "idx": 0,
    "name": "0",
    "path": "0_MyModelClass",
    "type": "custom_models.MyModelClass"
  }
]

This loads correctly if I use SentenceTransformers directly, but when loading in infinity it complains that the .auto_model attribute is missing (thrown by these lines https://github.com/michaelfeil/infinity/blob/main/libs/infinity_emb/infinity_emb/transformer/embedder/sentence_transformer.py#L81-L93 ). If this sort of custom model can be supported, or if you can give me some guidance on the correct way to save the model, that would be great.

Open source status & huggingface transformers.

• The model implementation is available on transformers
• The model weights are available on huggingface-hub
• I verified that the model is currently not running in the latest version pip install infinity_emb[all] --upgrade
• I made the authors of the model aware that I want to use it with infinity_emb & check if they are aware of the issue.

Start in libs/infinity_emb/infinity_emb/transformer/embedder/sentence_transformer.py at lines 81-93, then reproduce loading the reported nested custom SentenceTransformer model in SentenceTransformers and infinity_emb. Determine whether the model can be supported or whether its required save format needs documentation; done means the model loads successfully or clear guidance is provided.