Update app.py

app.py

@@ -6,6 +6,7 @@ import json
 from fastapi import FastAPI, UploadFile, File, Form, HTTPException, BackgroundTasks
 from fastapi.responses import StreamingResponse
 from pydantic import BaseModel
+from fastapi.middleware.cors import CORSMiddleware
 from utils import STT, TTS
 from data_ingestion import Ingest_Data 
 from RAG import app as rag_app, Ragbot_State, reload_vector_store
@@ -13,6 +14,14 @@ from RAG import app as rag_app, Ragbot_State, reload_vector_store
 # Initialize FastAPI
 app = FastAPI(title="LangGraph RAG Chatbot", version="1.0")
 
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_credentials=True,
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
+
 # --- Pydantic Models ---
 class ChatRequest(BaseModel):
     query: str
@@ -72,10 +81,8 @@ async def upload_document(
 
 @app.post("/chat")
 async def chat_endpoint(request: ChatRequest):
-    """
-    Robust Streaming Endpoint that logs events to console.
-    """
     config = {"configurable": {"thread_id": request.thread_id}}
+    
     inputs = {
         "query": request.query,
         "RAG": request.use_rag,
@@ -87,70 +94,21 @@ async def chat_endpoint(request: ChatRequest):
     }
 
     async def event_generator():
-        print(f"--- 🚀 Starting stream for {request.thread_id} ---")
-        
-        try:
-            # Iterate over all events
-            async for event in rag_app.astream_events(inputs, config=config, version="v2"):
-                event_type = event.get("event")
-                name = event.get("name", "")
-                
-                # Debug: print all events to see what's happening
-                print(f"Event: {event_type} | Name: {name}")
+        async for event in rag_app.astream_events(inputs, config=config, version="v1"):
+            kind = event["event"]
+            if kind == "on_chat_model_stream":
+                content = event["data"]["chunk"].content
                 
-                # Method 1: Check for on_chat_model_stream events (most reliable)
-                if event_type == "on_chat_model_stream":
-                    data = event.get("data", {})
-                    chunk = data.get("chunk")
-                    
-                    if chunk and hasattr(chunk, "content"):
-                        content = chunk.content
-                        if content:
-                            chunk_json = json.dumps({"content": content})
-                            yield f"data: {chunk_json}\n\n"
-                            print(f"✅ Yielded: {content[:50]}...")
-                
-                # Method 2: Alternative - check for any chunk with content
-                elif event_type in ["on_chain_stream", "on_llm_stream"]:
-                    data = event.get("data", {})
-                    chunk = data.get("chunk")
-                    
-                    # Handle different chunk types
-                    if chunk:
-                        content = None
-                        
-                        # AIMessageChunk
-                        if hasattr(chunk, "content"):
-                            content = chunk.content
-                        # String chunk
-                        elif isinstance(chunk, str):
-                            content = chunk
-                        # Dict with content
-                        elif isinstance(chunk, dict) and "content" in chunk:
-                            content = chunk["content"]
-                        
-                        if content:
-                            chunk_json = json.dumps({"content": content})
-                            yield f"data: {chunk_json}\n\n"
-                            print(f"✅ Yielded: {content[:50]}...")
-            
-            print("--- ✅ Stream completed ---")
-            
-        except Exception as e:
-            print(f"❌ Error in stream: {e}")
-            error_json = json.dumps({"error": str(e)})
-            yield f"data: {error_json}\n\n"
-        
-        # End of stream
-        yield "data: [DONE]\n\n"
+                if content:
+                    data = content.replace("\n", "\\n")
+                    yield f"data: {data}\n\n"
 
     return StreamingResponse(
-        event_generator(),
+        event_generator(), 
         media_type="text/event-stream",
         headers={
             "Cache-Control": "no-cache",
             "Connection": "keep-alive",
-            "Content-Type": "text/event-stream",
             "X-Accel-Buffering": "no",
         },
     )