Supplied by the connector to createBatchingStore, one per request type. A handler receives every request of
its type accumulated since the previous batch, together with a Broker for issuing nested requests. It
settles each Deferred in the batch with its result or error. The returned promise must resolve only once
every request in the batch has settled, including any nested requests issued through the broker.
Batches are never empty, so handlers need not guard against an empty one.
Batch handler for a single request type.
Supplied by the connector to createBatchingStore, one per request type. A handler receives every request of its type accumulated since the previous batch, together with a Broker for issuing nested requests. It settles each Deferred in the batch with its result or error. The returned promise must resolve only once every request in the batch has settled, including any nested requests issued through the broker.
Batches are never empty, so handlers need not guard against an empty one.