Function dataflow::render::sources::import_source

pub(crate) fn import_source<G>(
    dataflow_debug_name: &String, 
    dataflow_id: usize, 
    as_of_frontier: &Antichain<Timestamp>, 
    _: SourceInstanceDesc, 
    storage_state: &mut StorageState, 
    scope: &mut G, 
    materialized_logging: Option<Logger>, 
    src_id: GlobalId, 
    now: NowFn, 
    base_metrics: &SourceBaseMetrics
) -> ((Collection<G, Row>, Collection<G, DataflowError>), Rc<dyn Any>) where
    G: Scope<Timestamp = Timestamp>, 

Constructs a CollectionBundle and tokens from source arguments.

The first returned pair are the row and error collections, and the second is a token that will keep the source alive as long as it is held.