Fix upload 500 error, preload embeddings, add error handling

backend/api.py

@@ -21,6 +21,8 @@ def get_vectorstore():
     return load_documents(embedding_model=get_embeddings())
 
 
+
+
 BASE_DIR = Path("/app")
 upload_dir = BASE_DIR / "uploads"
 upload_dir.mkdir(parents=True, exist_ok=True)
@@ -48,6 +50,12 @@ system_stats = {
     "start_time": datetime.now().isoformat()
 }
 
+@app.on_event("startup")
+def startup_event():
+    print("🔄 Preloading embedding model...")
+    get_embeddings()
+    print("✅ Embedding model loaded")
+
 # Info about API
 @app.get("/")
 async def root():
@@ -104,28 +112,33 @@ async def get_stats():
 # This Endpoint upload Pdf and store into VectorDatabase
 @app.post("/upload")
 async def upload_file(file: UploadFile = File(...)):
-    if not file.filename.endswith(".pdf"):
-        raise HTTPException(status_code=400, detail="Only PDF files are supported")
+    try:
+        if not file.filename.endswith(".pdf"):
+            raise HTTPException(status_code=400, detail="Only PDF files are supported")
 
-    file_path = upload_dir / file.filename
+        file_path = upload_dir / file.filename
 
-    with open(file_path, "wb") as f:
-        shutil.copyfileobj(file.file, f)
+        with open(file_path, "wb") as f:
+            shutil.copyfileobj(file.file, f)
 
-    chunked_docs = get_chunked_docs(file_path)
+        chunked_docs = get_chunked_docs(file_path)
 
-    if not chunked_docs:
-        raise HTTPException(status_code=500, detail="No content extracted from PDF")
+        if not chunked_docs:
+            raise HTTPException(status_code=500, detail="No content extracted from PDF")
 
-    store_documents(chunked_docs, get_embeddings())
-    
-    # INCREMENT THE COUNTER HERE!
-    system_stats["total_uploads"] += 1
+        store_documents(chunked_docs, get_embeddings())
+
+        system_stats["total_uploads"] += 1
+
+        return {
+            "message": "PDF uploaded and indexed successfully",
+            "chunks_created": len(chunked_docs)
+        }
+
+    except Exception as e:
+        print("❌ UPLOAD ERROR:", str(e))  # <-- shows in HF logs
+        raise HTTPException(status_code=500, detail=str(e))
 
-    return {
-        "message": "PDF uploaded and indexed successfully",
-        "chunks_created": len(chunked_docs)
-    }
     
 from pydantic import BaseModel