apis/chat_api.py

import argparse
import uvicorn
import sys
import json

from fastapi import FastAPI
from fastapi.encoders import jsonable_encoder
from fastapi.responses import JSONResponse
from pydantic import BaseModel, Field
from sse_starlette.sse import EventSourceResponse
from utils.logger import logger
from networks.message_streamer import MessageStreamer
from messagers.message_composer import MessageComposer


class ChatAPIApp:
    def __init__(self):
        self.app = FastAPI(
            docs_url="/",
            title="HuggingFace LLM API",
            swagger_ui_parameters={"defaultModelsExpandDepth": -1},
            version="1.0",
        )
        self.setup_routes()

    def get_available_models(self):
        f = open('apis/lang_name.json', "r")
        self.available_models = json.loads(f.read())
        return self.available_models

    class ChatCompletionsPostItem(BaseModel):
        from_language: str = Field(
            default="auto",
            description="(str) `Detect`",
        )
        to_language: str = Field(
            default="en",
            description="(str) `en`",
        )
        text: str = Field(
            default="Hello",
            description="(str) `Text for translate`",
        )

    def chat_completions(self, item: ChatCompletionsPostItem):
        item_response = {
            "from_language": item.from_language,
            "to_language": item.to_language,
            "text": item.text,
            "translate": ""
        }
        json_compatible_item_data = jsonable_encoder(item_response)
        return JSONResponse(content=json_compatible_item_data)

    def setup_routes(self):
        for prefix in ["", "/v1"]:
            self.app.get(
                prefix + "/models",
                summary="Get available languages",
            )(self.get_available_models)

            self.app.post(
                prefix + "/translate",
                summary="translate text",
            )(self.chat_completions)


class ArgParser(argparse.ArgumentParser):
    def __init__(self, *args, **kwargs):
        super(ArgParser, self).__init__(*args, **kwargs)

        self.add_argument(
            "-s",
            "--server",
            type=str,
            default="0.0.0.0",
            help="Server IP for HF LLM Chat API",
        )
        self.add_argument(
            "-p",
            "--port",
            type=int,
            default=23333,
            help="Server Port for HF LLM Chat API",
        )

        self.add_argument(
            "-d",
            "--dev",
            default=False,
            action="store_true",
            help="Run in dev mode",
        )

        self.args = self.parse_args(sys.argv[1:])


app = ChatAPIApp().app

if __name__ == "__main__":
    args = ArgParser().args
    if args.dev:
        uvicorn.run("__main__:app", host=args.server, port=args.port, reload=True)
    else:
        uvicorn.run("__main__:app", host=args.server, port=args.port, reload=False)

    # python -m apis.chat_api      # [Docker] on product mode
    # python -m apis.chat_api -d   # [Dev]    on develop mode