Transforming 3PL Operations: Real-Time Data Sync Between Customers & upBin – Warehouse Management System via Google Pub/Sub

Our client uses upBin, a 3PL (Third-Party Logistics) Warehouse Management System (WMS), to manage inventory, orders, and goods movement for multiple customers. Before we implemented a proper integration, our process for handling Customer Purchase Orders, Purchase Receipts, Item Master Sync, Goods Receipts, and Goods Returns was manual and error-prone:

• Manual Order Creation: Customer teams had to create a Purchase Order (PO) in their system and manually send details to our team to re-enter into upBin.
• Duplicate Data Entry: For every goods receipt, item sync, or return, we had to manually update both systems (Customer ERP and WMS).
• Delays: Manual work caused delays in acknowledging receipts and syncing stock updates.
• High Error Rate: Typos, wrong quantities, and missed entries were common.
• Lack of Real-Time Visibility: Customers never had a live, accurate view of inventory and order processing status.

This led to frustration, extra manpower costs, and stock reconciliation issues at the end of each month.

Integration Objective

We wanted a seamless, automated, near-real-time integration that would:

• Receive POs directly from the customer’s system and create them in upBin automatically.
• Automatically sync item master data to avoid mismatched SKUs or descriptions.
• Push goods receipt data back to the customer system as soon as items are received.
• Push goods return data to customers automatically.
• Eliminate manual data entry, reduce errors, and improve visibility.

Solution: Google Pub/Sub Based Integration

Instead of using traditional API polling, we implemented Google Pub/Sub as the integration backbone:

Publisher (Customer ERP System)

The customer system publishes events like PO_CREATED, ITEM_MASTER_UPDATED, GOODS_RECEIVED, and GOODS_RETURNED into Google Pub/Sub topics.

Subscriber (upBin WMS Integration Layer)

Our integration service subscribes to these topics. When a message is published, it is instantly pushed to our WMS integration API. We create/update POs, receive goods, and sync items automatically in upBin.

Outbound Events (from upBin to Customer)

Our WMS also acts as a publisher for events like GRN_CREATED (Goods Receipt Note) or RETURN_COMPLETED. The customer system subscribes to these events and updates their ERP automatically.

Why Google Pub/Sub Instead of Regular API Integration?

Challenges Faced During Implementation

• Data Mapping: Carefully mapped customer PO fields with upBin’s internal data model to avoid mismatches.
• Idempotency: Ensured the same PO wasn’t created twice if a message was re-delivered.
• Security: Implemented IAM roles and service accounts so only authorized systems can publish/subscribe.
• Error Handling: Set up dead-letter topics to capture failed messages for later reprocessing.
• Testing: Simulated real-world cases (partial receipts, returns, item master changes) to verify reliability.

Benefits Achieved

• Zero Manual Entry: No more duplicate data entry across systems.
• Real-Time Processing: POs, receipts, and returns reflect in WMS within seconds.
• Fewer Errors: Data is consistent and accurate.
• Scalable: Handles spikes in PO volume with ease.
• Better Customer Experience: Instant confirmations and accurate stock visibility.
• Lower Operational Cost: Reduced manpower for order entry and reconciliation.

Conclusion

This integration has transformed the way we operate. By leveraging Google Pub/Sub, we moved from a slow, manual, error-prone process to a fast, reliable, real-time event-driven workflow. Our warehouse operations are now fully aligned with customer systems, resulting in better visibility, higher accuracy, and happier customers.