Update app.py

app.py

@@ -1,30 +1,21 @@
 from fastapi import FastAPI
-import joblib
-import pandas as pd
+from contextlib import asynccontextmanager
+import joblib, os, requests, pandas as pd
 from datetime import datetime
 from typing import Literal, Annotated
 from pydantic import BaseModel, Field
-import os
-import requests
 
-# ===============================
-# Configuration
-# ===============================
 HF_REPO = "samithcs/heart-rate-models"
 HEART_MODEL_FILENAME = "Heart_Rate_Predictor_model.joblib"
 ANOMALY_MODEL_FILENAME = "Anomaly_Detector_model.joblib"
 MODEL_DIR = os.path.join("artifacts", "model_trainer")
 os.makedirs(MODEL_DIR, exist_ok=True)
 
-# ===============================
-# Hugging Face download helper
-# ===============================
 def download_from_hf(filename):
     local_path = os.path.join(MODEL_DIR, filename)
     if os.path.exists(local_path):
         print(f"✅ {filename} already exists at {local_path}")
         return local_path
-
     url = f"https://huggingface.co/{HF_REPO}/resolve/main/{filename}"
     print(f"⬇️ Downloading {filename} from {url} ...")
     with requests.get(url, stream=True) as r:
@@ -35,10 +26,30 @@ def download_from_hf(filename):
     print(f"✅ Downloaded {filename} to {local_path}")
     return local_path
 
+# ===============================
+# Lifespan context
+# ===============================
+@asynccontextmanager
+async def lifespan(app: FastAPI):
+    global heart_model, heart_features, anomaly_model, anomaly_features
+
+    HEART_MODEL_PATH = download_from_hf(HEART_MODEL_FILENAME)
+    ANOMALY_MODEL_PATH = download_from_hf(ANOMALY_MODEL_FILENAME)
+
+    heart_model_artifacts = joblib.load(HEART_MODEL_PATH)
+    heart_model = heart_model_artifacts['model']
+    heart_features = heart_model_artifacts['feature_columns']
+
+    anomaly_model_artifacts = joblib.load(ANOMALY_MODEL_PATH)
+    anomaly_model = anomaly_model_artifacts['model']
+    anomaly_features = anomaly_model_artifacts['feature_columns']
+
+    yield
+
 # ===============================
 # FastAPI app
 # ===============================
-app = FastAPI(title="Health Monitoring API")
+app = FastAPI(title="Health Monitoring API", lifespan=lifespan)
 
 # ===============================
 # Request schemas