backend/services/hf_sync.py

import os
from huggingface_hub import HfApi
from dotenv import load_dotenv

load_dotenv()

def sync_db_to_hf():
    """
    Syncs the local SQLite database to a Hugging Face repository.
    This is useful for persisting data on ephemeral Hugging Face Spaces.
    """
    token = os.getenv("HF_TOKEN")
    repo_id = os.getenv("HF_REPO_ID") # e.g., "username/space-name"
    
    # Hugging Face Spaces automatically provide SPACE_ID
    if not repo_id:
        repo_id = os.getenv("SPACE_ID")
        
    if not token or not repo_id:
        print("HF_Sync: Missing HF_TOKEN or HF_REPO_ID. Skipping sync.")
        return False

    # Get the db path from database.py logic
    # We'll just use the constant path if it exists
    db_path = "/app/data/loan_db.db"
    
    # Fallback to local if not in docker
    if not os.path.exists("/app/data"):
        db_path = "./loan_db_v3.db"

    if not os.path.exists(db_path):
        print(f"HF_Sync: Database file not found at {db_path}. Skipping.")
        return False

    try:
        api = HfApi(token=token)
        print(f"HF_Sync: Uploading {db_path} to {repo_id}...")
        
        api.upload_file(
            path_or_fileobj=db_path,
            path_in_repo="data/loan_db_backup.db",
            repo_id=repo_id,
            repo_type="space" # Assuming it's a space, but could be 'dataset'
        )
        print("HF_Sync: Database successfully synced to Hugging Face Space.")
        return True
    except Exception as e:
        print(f"HF_Sync: Error during synchronization: {e}")
        return False