I know it's possible to create a fulfillment/inventory service and utilize the `fetch_stock` endpoint to essentially do whatever kind of inventory calculations desired (e.g. 300 total for a product, across all variants) however using this method there is a strong chance of overselling, as Shopify hits the `fetch_stock` endpoint only once per hour.
The only way I've found that kind of works - but it is a hack - is to toggle the `inventoryManagement` property on the variant to `SHOPIFY` and back to `FULFILLMENT_SERVICE` in back-to-back requests.
Is there a better way to kindly ask Shopify to hit the `fetch_stock` endpoint, e.g. after an order is placed?
I also found this app: https://apps.shopify.com/connected-inventory which seems to take a different approach - I'm not 100% sure - I think they are using Shopify inventory and manually adjusting inventory levels via the API (e.g. after an order is placed)