Lesson 1 of 5
Integration technologies
10 min
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An SAP S/4HANA system rarely works alone. Orders arrive from customers, purchase orders leave for suppliers, payments go to banks, and a web portal asks for order status every few seconds. Each of those conversations runs on an integration technology: an agreed way for two systems to exchange data. If you test, design or support SAP, you need to recognize the main technologies on sight, because each one fails, is monitored and is tested in its own way.
This course uses Contoso Motor Co. as its running example. Contoso is converting its SAP ECC 6.0 EHP 8 system to SAP S/4HANA Private Edition (systems CMD, CMQ and CMP). Its integration lead, Theo, owns an inventory of about 60 interfaces that must keep working on the day after go-live.
The six technologies you will meet
| Technology | What it is | Typical use at Contoso |
|---|---|---|
| IDoc (Intermediate Document) | SAP's structured document container for business messages, with a control record, data records and status records. Usually exchanged asynchronously. | Inbound sales orders from Great Lakes Fleet Services over EDI; outbound purchase orders to Lakeside Components |
| RFC / BAPI | Remote Function Call lets one system call a function module in another. BAPIs are released function modules that represent business object methods, such as creating a sales order. | An older shop-floor system in Detroit posts confirmations by calling a BAPI |
| OData | An open REST-based protocol (an OASIS standard) for reading and changing data over HTTP, with a published metadata document. | Contoso's customer portal reads order status; SAP Fiori apps use OData behind every screen |
| SOAP web services | XML messages over HTTP described by a WSDL contract. SAP S/4HANA offers many SOAP APIs, often for asynchronous business-to-business messages. | A tax or logistics partner exchanges XML documents with a fixed contract |
| Events | A short notification that something happened ("business partner changed"), published to a broker that delivers it to any subscriber. | Planned: notify the portal when a delivery is posted instead of the portal polling for it |
| Files | A batch of records written to a file and moved by a transfer protocol on a schedule. | Bank payment files and daily bank statements; a nightly price list for a distributor |
The main integration technologies in an SAP S/4HANA landscape.
SAP groups the remote interfaces it supports into released APIs: OData services and SOAP services for synchronous and asynchronous calls from outside the system, plus events for event-driven communication. IDocs and BAPIs are older but still heavily used in on-premise and Private Edition landscapes, especially after a system conversion, which carries existing interfaces over.
How to tell them apart
In practice you identify a technology by where its traces appear. An IDoc has a number and a status history you can read in transactions such as WE02. An RFC call leaves entries in the RFC destination configuration (SM59) and, if it is transactional and fails, a queue entry. An OData call is an HTTP request to a URL under /sap/opu/odata/ or /sap/opu/odata4/, with an HTTP status code and an error log. A SOAP message is logged in the web service monitoring. A file has a name, a timestamp and a record count.
| Technology | Style | Where you see it fail | Typical tester check |
|---|---|---|---|
| IDoc | Asynchronous | IDoc status (for example 51, application document not posted) | Status 53 and the posted document in the app |
| RFC / BAPI | Usually synchronous | Return messages; RFC errors in the calling system | Return table has no errors; the document exists |
| OData | Synchronous | HTTP status 4xx or 5xx and the gateway error log | Correct status code, payload and data change |
| SOAP | Sync or async | SOAP fault or web service monitor entry | Response or acknowledgment, then the posted document |
| Events | Asynchronous | Undelivered event at the broker or subscriber | Subscriber received the event and acted on it |
| File | Asynchronous batch | Missing file, wrong count, rejected records | Record counts and totals match source and target |
What would you do?
Priya, the test lead, asks Theo for the interface list for the first integration test cycle. Theo's spreadsheet lists each interface by partner name only ("Great Lakes orders", "Bank statements"). What should Priya ask Theo to add first?
- The main SAP integration technologies are IDoc, RFC/BAPI, OData, SOAP web services, events and files.
- Describe every interface in four layers: business message, format, protocol and platform.
- Each technology fails and is monitored in a different place; tests must collect evidence there.
- A system conversion carries existing IDoc and RFC interfaces over, so they stay in scope for testing.
Check your understanding · not graded
Lesson check
1. Which record in an IDoc tells you the sender, receiver and IDoc type?
2. A customer portal asks SAP S/4HANA for a list of open orders over HTTPS and gets JSON back. Which technology is this most likely to be?
3. Why do IDoc and BAPI interfaces stay in scope after a system conversion?