fix[cl-fastapi]: use json for request content-type (and update llama-index)

templates/types/streaming/fastapi/app/api/routers/chat.py

@@ -2,11 +2,11 @@ from typing import List
 
 from fastapi.responses import StreamingResponse
 
-from app.utils.json import json_to_model
 from app.utils.index import get_index
 from fastapi import APIRouter, Depends, HTTPException, Request, status
 from llama_index import VectorStoreIndex
-from llama_index.llms.base import MessageRole, ChatMessage
+from llama_index.llms.base import ChatMessage
+from llama_index.llms.types import MessageRole
 from pydantic import BaseModel
 
 chat_router = r = APIRouter()
@@ -24,9 +24,7 @@ class _ChatData(BaseModel):
 @r.post("")
 async def chat(
     request: Request,
-    # Note: To support clients sending a JSON object using content-type "text/plain",
-    # we need to use Depends(json_to_model(_ChatData)) here
-    data: _ChatData = Depends(json_to_model(_ChatData)),
+    data: _ChatData,
     index: VectorStoreIndex = Depends(get_index),
 ):
     # check preconditions and get last message

templates/types/streaming/fastapi/app/utils/json.py

-import json
-from typing import TypeVar
-from fastapi import HTTPException, Request
-
-from pydantic import BaseModel, ValidationError
-
-
-T = TypeVar("T", bound=BaseModel)
-
-
-def json_to_model(cls: T):
-    async def get_json(request: Request) -> T:
-        body = await request.body()
-        try:
-            data_dict = json.loads(body.decode("utf-8"))
-            return cls(**data_dict)
-        except (json.JSONDecodeError, ValidationError) as e:
-            raise HTTPException(
-                status_code=400, detail=f"Could not decode JSON: {str(e)}"
-            )
-
-    return get_json

templates/types/streaming/fastapi/pyproject.toml

@@ -9,7 +9,7 @@ readme = "README.md"
 python = "^3.11,<3.12"
 fastapi = "^0.104.1"
 uvicorn = { extras = ["standard"], version = "^0.23.2" }
-llama-index = "^0.8.56"
+llama-index = "^0.9.19"
 pypdf = "^3.17.0"
 python-dotenv = "^1.0.0"