## Overview
youzan.items.onsale.get pages through a shop's on-sale items, returning item_id, title, price, quantity (total stock), item_no (merchant code) and SKU details (sku_id, sku_no, price, quantity). Its companion youzan.items.inventory.get covers warehouse (delisted) items — together they enumerate the full catalog.
### Request essentials
1. POST with Content-Type: application/json; access_token in the URL query; use the documented version in the path (e.g. 4.0.0).
2. Paginate via page_no/page_size; incremental pulls use an update_time window (optional filters like title search q or tag_id per the docs).
3. SKU-level fields are the key to stock calibration: sku_no is the cross-system product key, so a one-to-one mapping between Youzan sku_no and ERP material codes must exist before integration.
4. quantity is Youzan's selling stock; comparing it with the ERP stock ledger exposes sync gaps (oversell vs silent stockouts).
### Typical pipeline
ERP product master → Qeasy field mapping (code, barcode, category, price) → Youzan item create/update; a scheduled job pulls Youzan items and stock back via this API and produces an ERP-versus-Youzan divergence report for operations to fix.
### Pairing with stock APIs
This list returns per-item totals; precise SKU-level stock maintenance goes through the SKU stock-update API addressed by sku_id or item_no plus sku_no. Delisted items are absent here, so a full-catalog audit combines youzan.items.inventory.get with this endpoint, merging and deduplicating on item_id to reconstruct the complete catalog.