app/cache/tenant_members.py

# app/cache/tenant_members.py
from typing import Dict, List, Set
from threading import Lock
from sqlalchemy.orm import Session
from app.models import User, Admin

# Cache format: { tenant_id: {"user-1", "user-2", "admin-10"} }
tenant_members_cache: Dict[int, Set[str]] = {}
lock = Lock()

def get_tenant_connection_ids(tenant_id: int, db: Session) -> Set[str]:
    """
    Returns cached connection IDs for a tenant.
    If not cached, it queries the DB, populates the cache, and returns the data.
    """
    with lock:
        if tenant_id in tenant_members_cache:
            return tenant_members_cache[tenant_id]

    # --- Not in cache, so load from PostgreSQL ---
    tenant_users = db.query(User.id).filter(User.admin_id == tenant_id).all()
    # The admin is also a member of their own tenant
    tenant_admin = db.query(Admin.id).filter(Admin.id == tenant_id).first()

    connection_ids = {f"user-{uid}" for uid, in tenant_users}
    if tenant_admin:
        connection_ids.add(f"admin-{tenant_admin.id}")
    
    # Populate the cache
    with lock:
        tenant_members_cache[tenant_id] = connection_ids
    
    return connection_ids