What is still on order for a product, grouped by the variant it is coming for

Open orders carrying any variant of one product, grouped under the variant rather than under the order: one entry per variant that has something inbound, each with po_count, to_count (transfer orders), proposal_count and the orders themselves.

Each order in purchase_orders carries its id and name, order_type (PURCHASE, TRANSFER or MANUFACTURING), is_proposal, status, expected_delivery_date, supplier and location, the line_items and deliveries for that variant alone, ordered_quantity and delivered_quantity for that variant alone, has_delivery_delay (true once the expected date is in the past) and supplier_signals. total_ordered and total_delivered on the group are those two summed across its orders and are being retired; sum the orders yourself rather than depending on them.

Fully delivered and cancelled orders are not here. A product with nothing inbound answers purchase_orders_grouped_by_variant: [], which is the empty case and not an error.

This is the product's own view. For the same question against a single variant, read the variant's incoming purchase orders; for the orders themselves, with their whole line set, read the purchase orders resource.

Scope: products:read.