def _get_instances_from_catalog(get_from_catalog_func, user):
    """Get component instances from catalog

    Fetching instances from the catalog covers the deployment cases where
    components registered successfully regardless of their health check status.

    Args
    ----
    get_from_catalog_func: func() -> (don't care, dict)
        Look at unittests in test_discovery to see examples
    user: (string) user id

    Returns
    -------
    List of unique component instance names
    """
    # Get all services and filter here by user
    response = get_from_catalog_func()
    return list(set([ instance for instance in response[1].keys() if user in instance ]))