Inventory ATP

Available-To-Promise (ATP) is the ability to determine when products will be available for delivery based on current inventory, reservations, and incoming purchase orders. ATP calculations help provide realistic delivery date promises to customers and optimize inventory allocation across orders.

Omnium provides a pluggable ATP provider system that can calculate availability using internal data or integrate with external systems like ERP.

What is ATP?

ATP answers the question: "When can I deliver this product to the customer?"

Unlike simple stock checks that only consider current inventory, ATP looks forward in time by considering:

• Current on-hand inventory - Physical stock available now
• Reserved inventory - Stock already committed to other orders
• Incoming inventory - Future deliveries from purchase orders
• Reservations on future stock - Orders already allocated to incoming purchase orders

This allows Omnium to:

• Promise delivery dates even when current stock is insufficient
• Allocate incoming purchase order quantities to waiting orders
• Update product expected delivery dates automatically
• Validate orders against realistic availability

Key Concepts

ATP Entry

ATP data is stored on inventory items as a list of future availability entries. Each entry represents expected inventory from a purchase order delivery.

ATP Request

When calculating ATP, a request specifies what availability information is needed.

ATP Result

The result of an ATP calculation provides availability information.

How ATP Works in Omnium

ATP Data Flow

Purchase Orders with Expected Delivery Dates
              |
              v
+---------------------------+
| ATP Index Recalculation   |
| - Get active PO lines     |
| - Calculate reservations  |
| - Build ATP entries       |
+---------------------------+
              |
              v
+---------------------------+
| Store ATP on Inventory    |
| (per SKU/warehouse)       |
+---------------------------+
              |
              v
+---------------------------+
| ATP Calculation           |
| - Sum current + future    |
| - Check vs. requested qty |
| - Determine delivery date |
+---------------------------+
              |
              v
+---------------------------+
| Update product delivery   |
| dates and validate orders |
+---------------------------+

When ATP is Calculated

ATP recalculation is triggered in several scenarios:

1. Order workflow - The CalculateAtp order action recalculates ATP for SKUs in the order when orders reach certain statuses (typically New or OrderCanceled)
2. Purchase order changes - When purchase orders are created, updated, or deliveries arrive
3. Manual trigger - ATP can be recalculated on demand for specific SKUs
4. Background processing - ATP can be queued for asynchronous recalculation

ATP Calculation Algorithm

When calculating whether a quantity can be delivered:

1. Get current availability

   • Calculate available now as: on-hand inventory minus reserved inventory

2. If no ATP entries exist - Only current stock is considered

3. If ATP entries exist - Accumulate future availability by date:

   • Sort ATP entries by date (earliest first)
   • For each entry, add available quantity to cumulative total
   • Check if cumulative meets the requested quantity
   • If a requested delivery date is specified, verify the date is achievable

4. Return result with the earliest date when quantity is available

Package Products

For package products (bundles), ATP is calculated specially:

• Each component's ATP is calculated separately
• The package delivery date is the latest component delivery date
• If any component cannot be delivered, the package cannot be delivered
• Components that are available now don't affect the delivery date

ATP Providers

ATP providers implement the actual calculation logic. Omnium supports multiple providers that can be configured per tenant.

No Provider Configured

When no ATP provider is configured:

• ATP data is not calculated or stored on inventory items
• Product expected delivery dates are not automatically updated
• Cart/order validation only considers current inventory levels
• The CalculateAtp order action has no effect

This is suitable when:

• Inventory is managed entirely in an external system
• You only need simple stock availability (in stock / out of stock)
• Expected delivery dates are managed manually or through other mechanisms

ATP Validation

Omnium validates cart and order inventory considering ATP data:

1. Skips validation for pre-orders (pre-orders don't require current availability)
2. Checks current availability against line item quantities
3. If RequestedDeliveryDate is set - Also considers ATP entries up to that date
4. Returns validation errors for items that cannot be fulfilled

The validator considers inventory from all available warehouses for the order's store, including:

• Directly assigned warehouses
• Primary warehouses
• Warehouses linked through store configuration

Order Actions

CalculateAtp Order Action

Key: CalculateAtp

Recalculates ATP for products in the order that have purchase order reservations.

Default Statuses: New, OrderCanceled

Properties:

Behavior:

1. Gets SKUs from order lines with reserved inventory from purchase orders
2. Updates ATP data on inventory items
3. Unless SkipProductUpdate is true, also updates product expected delivery dates

Product Expected Delivery Date

ATP calculations can automatically update the ExpectedDeliveryDate on product variants. This provides visibility into when out-of-stock products will be available.

The update process:

1. Calculate ATP for product SKUs
2. For regular products: Set expected delivery date based on when quantity becomes available
3. For packages: Set to the latest component delivery date
4. Only updates products whose delivery date actually changed
5. Triggers product events for audit trail

Note: Only primary warehouses are considered when updating product delivery dates.

Configuration

ATP providers are configured in tenant settings:

{
  "InventoryManagement": {
    "AtpProviders": [
      {
        "Key": "OmniumAtpProvider",
        "AtpCalculationType": null
      }
    ]
  }
}

For detailed configuration, see Inventory Configuration.

Related Topics

• Inventory Configuration
• Virtual Stock Locations
• Inventory API