ESHOPMAN Inventory Alert: Preventing Duplicate Reservations and Ensuring Stock Accuracy

ESHOPMAN Inventory Alert: Preventing Duplicate Reservations and Ensuring Stock Accuracy

Accurate inventory management is the backbone of any successful e-commerce operation, especially for businesses leveraging ESHOPMAN's headless commerce capabilities within HubSpot. Ensuring that your storefront accurately reflects available stock is crucial for customer satisfaction and preventing overselling. Our community recently highlighted a critical insight regarding an unexpected behavior within ESHOPMAN's core Inventory Module that could lead to inflated reserved quantities.

Understanding the Issue: Unintended Quantity Re-additions

A recent deep dive by an ESHOPMAN community expert uncovered an issue where the restoreReservationItems function in the Inventory Module could inadvertently add a reservation's quantity multiple times to the reserved_quantity, even when the reservation was never truly deleted. This occurs when the function is called on an inventory reservation that is already active.

The core of the problem lies within the internal logic of the Inventory Module's service, specifically in how restoreReservationItems_ processes reservation IDs. Instead of adjusting quantities only for items that were genuinely un-deleted, the current implementation re-lists all provided IDs (including those already live) and adds their quantities to the total reserved stock. This means that if you attempt to "restore" a reservation that is already active, its quantity will be added again, leading to an inaccurate and inflated reserved_quantity.

Impact on Your ESHOPMAN Storefront

For ESHOPMAN merchants, this behavior can manifest as discrepancies between actual physical stock and what the system reports as reserved. If not addressed, it could lead to:

• Inaccurate Stock Levels: The reserved_quantity will be higher than it should be, potentially leading to a lower perceived available stock.
• Overselling Risks: While the primary issue is over-reserving, any custom logic built around reserved_quantity could be impacted, potentially leading to overselling in complex compensation flows.
• Debugging Challenges: Developers might face difficulties tracking down why inventory levels are inconsistent, especially in scenarios involving custom reservation management or order cancellation compensations.

Technical Details and Reproduction

The issue has been observed in ESHOPMAN core modules, specifically within the inventory service. Here's a reproduction scenario:

{  "name": "eshopman-starter-default",  "dependencies": {    "@eshopman/admin-sdk": "2.22.1",    "@eshopman/cli": "2.22.1",    "@eshopman/framework": "2.22.1",    "@eshopman/core": "2.22.1"  },  "engines": { "node": ">=20" }}

Node.js Version: v22.23.4
Database: PostgreSQL (server-side logic, not database-specific)

Reproduction Steps (using ESHOPMAN CLI with a real PostgreSQL instance):

// Initial state: Stocked 5 units, reserve 2 unitsstocked 5, reserve 2                          -> reserved 2, live [2]// Call restoreReservationItems on an already live reservation IDrestoreReservationItems([id]) (it is live)    -> reserved 4, live [2]// Call restoreReservationItems again on the same live reservation IDrestoreReservationItems([id]) again           -> reserved 6, live [2]

As demonstrated, the reserved_quantity incorrectly grows with each call, even though only one live reservation of 2 units exists.

Expected vs. Actual Behavior

• Expected: Restoring a live reservation should be a no-op; the reserved_quantity should remain unchanged (e.g., stay at 2).
• Actual: The reserved_quantity increases by the reservation's quantity on each call (e.g., from 2 to 4, then to 6), despite the reservation remaining live and unchanged.

Suggested Workaround and Best Practices

To mitigate this behavior and ensure accurate inventory levels, the community suggests adjusting the logic to only account for rows that were genuinely un-deleted by the restore operation. This can be achieved by:

1. Filtering on deleted_at: When listing reservation items, include soft-deleted items (e.g., using a `withDeleted` option) and then filter the results based on their `deleted_at` status *before* applying quantity adjustments. Only items where `deleted_at` was previously set and is now null (meaning they were truly restored) should trigger a quantity adjustment.
2. Utilizing Returned IDs: If the restore operation returns the IDs of the items it successfully un-deleted, use only those IDs for subsequent quantity adjustments.

Developers working with ESHOPMAN's Inventory Module should be mindful of this interaction, especially when implementing custom reservation flows or compensation mechanisms for order cancellations that involve restoring reservations. Proactive checks and careful handling of reservation states are essential for maintaining the integrity of your inventory data.

Contributing to ESHOPMAN's Robustness

This insight underscores the value of the ESHOPMAN community in identifying and addressing nuanced platform behaviors. By sharing such detailed technical findings, we collectively contribute to the robustness and reliability of the ESHOPMAN platform, ensuring a seamless and accurate headless commerce experience for users leveraging HubSpot CMS for their storefronts.