Sage 300 and Coupa integration

What moves between them

The integration flows primarily from Coupa into Sage 300. Purchase orders created in Coupa are polled and posted into Sage 300 as approved purchase order batches, with Coupa supplier records mapped to Sage 300 vendor records. Supplier master data is synchronized bidirectionally so Coupa procurement reflects Sage 300 vendor changes, and new vendors created in Sage 300 can provision in Coupa. Invoices received in Coupa can optionally flow to Sage 300 AP invoice batches for posting into the general ledger. Sync happens continuously via webhook ingestion on Coupa events and scheduled polling of Sage 300 for new purchase orders awaiting approval.

How ml-connector handles it

ml-connector stores both credential sets encrypted: the Sage 300 HTTP Basic credentials in uppercase and the Coupa OAuth 2.0 client credentials with automatic token refresh on 401 response. It accepts the customer's Sage 300 IIS hostname and constructs REST calls using the OData syntax required by Sage 300, filtering on document dates and handling pagination with the $skip and $top parameters. Coupa webhooks are registered at the customer's instance and ingested directly, with signature verification via HMAC-SHA256. Supplier mapping happens through lookup tables so a Coupa supplier ID matches the corresponding Sage 300 vendor code. Since Sage 300 is self-hosted and reachable only by the customer's network, ml-connector can poll it on a scheduled cadence tied to business hours to avoid IIS AppPool timeout. Coupa rate limit responses (HTTP 429) trigger exponential backoff with jitter. Every purchase order, supplier, and invoice record carries full audit trail with payload replay capability if a downstream post fails.

A real-world example

A mid-market distributor runs Sage 300 for accounts payable and procurement on premises and uses Coupa for enterprise spend visibility and supplier management across 15 regional offices. Before the integration, procurement teams created purchase orders in Coupa but the AP team had to manually key or import those orders into Sage 300, then match incoming Coupa invoices to the Sage 300 PO lines for approval and accrual. Supplier master data was maintained separately in both systems, causing mismatches when a new vendor joined. With Sage 300 and Coupa connected, purchase orders flow automatically into Sage 300, invoices are matched to existing POs, and supplier records stay aligned bidirectionally. The manual PO entry step is eliminated, and month-end accruals require only verification, not re-keying.

What you can do

• •Sync purchase orders from Coupa into Sage 300 as approved PO batches, mapped to the correct vendor records.
• •Keep vendor master data aligned between Sage 300 and Coupa through bidirectional supplier synchronization.
• •Ingest Coupa webhooks for real-time PO and supplier events, with fallback to Sage 300 polling for new orders awaiting approval.
• •Authenticate Sage 300 using HTTP Basic Auth with uppercase credentials and Coupa using OAuth 2.0 client credentials with automatic token refresh.
• •Track every purchase order and supplier record with full audit trail, supporting replay if a post to Sage 300 fails.

Questions

Which direction does data move between Sage 300 and Coupa?

The primary flow is from Coupa into Sage 300. Purchase orders and invoices created in Coupa are posted into Sage 300. Supplier master data flows bidirectionally, so vendor changes in Sage 300 can update Coupa and new suppliers created in Coupa can provision in Sage 300 if configured.

How does ml-connector handle Sage 300's self-hosted API and lack of webhooks?

ml-connector accepts the customer's Sage 300 IIS hostname and polls it on a scheduled cadence using OData filters on document dates and pagination. Coupa webhooks are registered at the customer's Coupa instance and ingested in real time with signature verification, providing immediate notification of PO and supplier changes while Sage 300 remains pull-only.

What happens if the IIS server is slow or times out?

Sage 300 IIS can timeout under heavy request loads. ml-connector manages this by staggering polls during business hours, respecting the 30-second request timeout, and avoiding large batches that would trigger AppPool recycling. Large volume syncs are broken into smaller chunks with exponential backoff between requests.