16 Create controller function that will handle InventoryItem route queries
Closes #16 (closed)
endpoint route
- For listing all InventoryItem /api/fhir/r5/InventoryItem
- listing single product /api/fhir/r5/InventoryItem/product/{code}
- listing single product /api/fhir/r5/InventoryItem/product-model/{code}