Inventory management

Understand InventoryEntry

The InventoryEntry entity acts as the single source of truth for the physical stock level of a specific Product Variant at a given location or channel. It's crucial to understand its structure and attributes.

InventoryEntry attributes:

• id: a unique identifier automatically generated by Composable Commerce for each InventoryEntry.
• version: an integer representing the current version of the InventoryEntry. This value is used for optimistic concurrency control.
• key: a user-defined, unique identifier for the InventoryEntry. Setting a key can be beneficial for simplifying queries and updates. For example, you could use a combination of the SKU and warehouse location as the key.
• sku: the ProductVariant SKU associated with this InventoryEntry. This attribute links the inventory record to a specific Product Variant. Importantly, the SKU does not have to exist as a Product within Composable Commerce. This allows you to manage inventory for products even before they are fully defined in your product catalog.
• supplyChannel: a ChannelReference that indicates the specific channel that supplies this inventory. This is important for multi-channel inventory management, allowing you to track inventory levels separately for different sales channels like online stores, marketplaces, or physical stores.
• quantityOnStock: the total amount of stock currently available, calculated as availableQuantity + reserved. This represents the overall physical stock level.
• availableQuantity: the portion of the quantityOnStock that is currently available for sale. This value is dynamically updated based on orders, reservations, and other inventory movements. It's crucial to use this field for determining what can be sold to avoid overselling.
• restockableInDays: an informational field that represents the typical restocking frequency in days. This field's interpretation depends on your business logic and how you utilize it within your application. For instance, you might use it to display estimated restocking times to customers or to trigger automated replenishment processes.
• expectedDelivery: an informational field that indicates the estimated date and time of the next restock. Similar to restockableInDays, its meaning is context-dependent and can be leveraged for various purposes within your inventory management workflows.
• custom: allows you to add one or more Custom Fields to the InventoryEntry. This provides flexibility in extending the data model to store additional information relevant to your specific inventory management needs. For example, you could use Custom Fields to track batch numbers, expiry dates, or specific storage locations within a warehouse.
• createdAt: a timestamp indicating when the InventoryEntry was initially created in the system.
• createdBy: information about the user or system that created the InventoryEntry.
• lastModifiedAt: a timestamp indicating the last time the InventoryEntry was modified.
• lastModifiedBy: information about the user or system that last modified the InventoryEntry.

Understand quantityOnStock

The quantityOnStock attribute within an InventoryEntry is central to managing product availability effectively. However, its use can be tailored to your specific business rules and inventory management strategies.

Here are some potential use cases for quantityOnStock:

• Aggregated inventory: in scenarios with multiple warehouses or fulfillment centers, quantityOnStock can represent the total available stock across all locations. This aggregated view simplifies availability checks but requires careful management to avoid overselling from individual locations.
• Virtual inventory: quantityOnStock can be used to represent a calculated value that goes beyond physical stock levels. This might include anticipated incoming shipments, pre-ordered items, or stock allocated for specific channels or promotions. Using virtual inventory allows for greater flexibility but demands accurate forecasting and management to prevent discrepancies between virtual and actual stock levels.
• Buffered inventory: safety buffers, either positive or negative, can be applied to the quantityOnStock to mitigate risks associated with inventory fluctuations. Negative buffers account for potential delays in inventory updates or in-transit inventory, preventing overselling. Conversely, positive buffers might represent expected incoming stock, allowing for pre-orders or backorders.

The key takeaway is that the effective meaning of quantityOnStock is determined by your business logic and how you leverage the inventory features provided by Composable Commerce. You should define what this value represents within your system and ensure consistent application of your chosen logic across all integrations and processes. This clarity is essential for accurate inventory reporting, effective order management, and preventing stock-outs or overselling scenarios.

Product Variant availability: Strong vs. Eventual Consistency

Product Variants have a system generated field named availability (of type:ProductVariantAvailability), containing all InventoryEntry records for a SKU. The values are added to the Product by the system using an eventually consistent approach. This means there's a distinction between the strongly consistent inventory data stored in InventoryEntry records and the aggregated representation of availability on the ProductVariant itself.