server.py

from transformers import pipeline
import litserve as ls
from fastapi import Depends, HTTPException
from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer
import os


class TopicBanningAPI(ls.LitAPI):
    def setup(self, device):
        model_name = "facebook/bart-large-mnli"
        self.pipeline = pipeline("zero-shot-classification", model=model_name, token=os.getenv("HF_TOKEN"))

    def decode_request(self, request):
        return request

    def predict(self, query):
        text = query["text"]
        topics = query["topics"]
        return self.pipeline(text, topics)

    def encode_response(self, output):
        return output 

    def authorize(self, auth: HTTPAuthorizationCredentials = Depends(HTTPBearer())):
        if auth.scheme != "Bearer" or auth.credentials != os.getenv("auth_token"):
            raise HTTPException(status_code=401, detail="Bad token")


if __name__ == "__main__":
    api = TopicBanningAPI()
    server = ls.LitServer(api, devices="cpu", accelerator="cpu")
    server.run(port=7860)