fixed streaming issue

main.py

@@ -1,30 +1,3 @@
-from fastapi import FastAPI, Request
-from fastapi.responses import StreamingResponse, JSONResponse
-from pydantic import BaseModel
-import requests
-import time
-import json
-from typing import List, Optional
-from models import AVAILABLE_MODELS
-
-app = FastAPI()
-
-def unix_id():
-    return str(int(time.time() * 1000))
-
-class Message(BaseModel):
-    role: str
-    content: str
-
-class ChatRequest(BaseModel):
-    messages: List[Message]
-    model: str
-    stream: Optional[bool] = False
-
-@app.get("/v1/models")
-async def list_models():
-    return {"object": "list", "data": AVAILABLE_MODELS}
-
 @app.post("/v1/chat/completions")
 async def chat_completion(request: ChatRequest):
     headers = {
@@ -42,6 +15,7 @@ async def chat_completion(request: ChatRequest):
 
     if request.stream:
         def event_stream():
+            sent_done = False
             with requests.post(
                 "https://www.chatwithmono.xyz/api/chat",
                 headers=headers,
@@ -51,9 +25,13 @@ async def chat_completion(request: ChatRequest):
             ) as response:
                 for line in response.iter_lines(decode_unicode=True):
                     if line.startswith("0:"):
-                        piece = line[2:]
-                        yield f"data: {json.dumps({'choices': [{'delta': {'content': piece}, 'finish_reason': None}]})}\n\n"
-                    elif line.startswith(("e:", "d:")):
+                        try:
+                            content_piece = json.loads(line[2:])
+                            yield f'data: {json.dumps({"choices": [{"delta": {"content": content_piece}, "finish_reason": None}]})}\n\n'
+                        except:
+                            continue
+                    elif line.startswith(("e:", "d:")) and not sent_done:
+                        sent_done = True
                         yield "data: [DONE]\n\n"
         return StreamingResponse(event_stream(), media_type="text/event-stream")
 
@@ -72,7 +50,7 @@ async def chat_completion(request: ChatRequest):
                 if chunk.startswith("0:"):
                     try:
                         piece = json.loads(chunk[2:])
-                        assistant_response += piece
+                        assistant_response += piece  # this is just a string fragment
                     except:
                         continue
                 elif chunk.startswith(("e:", "d:")):
@@ -91,7 +69,7 @@ async def chat_completion(request: ChatRequest):
                 "index": 0,
                 "message": {
                     "role": "assistant",
-                    "content": assistant_response
+                    "content": assistant_response  # correctly concatenated string
                 },
                 "finish_reason": "stop"
             }],