backend/API/core/database.py

from fastapi import HTTPException, status
from motor.motor_asyncio import AsyncIOMotorClient, AsyncIOMotorDatabase

from core.config import settings

client: AsyncIOMotorClient | None = None
db: AsyncIOMotorDatabase | None = None


async def connect_to_mongo():
    """Connect to MongoDB."""
    global client, db
    client = AsyncIOMotorClient(settings.MONGODB_URL)
    db = client[settings.MONGODB_DB_NAME]
    # Force an actual round-trip so startup fails fast on bad URI/network/auth.
    await client.admin.command("ping")
    print("Connected to MongoDB")


async def close_mongo_connection():
    """Close MongoDB connection."""
    global client
    if client:
        client.close()
    print("Closed MongoDB connection")


def get_db() -> AsyncIOMotorDatabase:
    """Get database instance."""
    if db is None:
        raise HTTPException(
            status_code=status.HTTP_503_SERVICE_UNAVAILABLE,
            detail="Database is not initialized",
        )
    return db