Where do to find SAP service for OutSystems
You can find SAP services in the SAP API HUB. In this HUB you will find all web services available for SAP products like S/4HANA and S/4HANAcloud. Notice that many services are still SOAP and will probably remain so. Although SAP claims most services are working out-of-the-box there still might be some work to do before you can actually have a working SAP integration working. In reality, SAP and OutSystems connection is a server-to-server connection. OData as such was designed with server-to-client scenarios in mind. This does not mean that you cannot use SAP Odata services in OutSystems, it just means that a different approach to the integration you need might be simpler and faster to implement. OutSystems BAPI integration gives you a list of all alternative remote function calls (RFCs) you can use to integrate with SAP. From 2021 SAP started dusting off their BAPI's and those that are still valuable are whitelisted, even in the S/4HANAcloud version. You can call these services through the SAP Business Technology Platform. (BTP) Make sure to implement the right security and have all the licensing in order.
To consume an SAP OData service in OutSystems you need to:
1)Obtain the service specification file from SAP API Business Hub
2)Consume the service in Service Studio
3)Make some final adjustments
Here, in the OutSystems Forge, you can find a sample implementation of the tasks described in this topic of OutSystems SAP Integration.
Obtaining the service specification. Steps to obtain the service notifications are following:
In the first step, you must identify the service you want to consume and download the service specification. Do the following:
1)Open the SAP API Business Hub. Note there are two ERP systems that SAP offers. S/4HANA Cloud and S/4HANA. Most of the services are available on the S/4HANA Cloud, since all services are first implemented on the cloud, the service that you are looking for might not (yet) be available on S/4HANA. 
2)Search for the service in the search box., the first thing you might notice is that there are different versions in ODATA specifications ODATA V2 and V4 but also many of the APIs listed by the SAP service hub are not ODATA at all but SOAP. Luckily OutSystems can also deal with SOAP! Since 2021 SAP event started whitelisting BAPIs in the cloud offering. This in effect means that SAP has left their "everything will become ODATA" strategy. This does also mean when you search for API's you will have to choose the right API and implement them using OutSystems as BAPI directly or as Webservice.
In the example presented in this guide, we are using the "Product Master - Create, Read, Update, Delete master data for products" service from SAP S/4HANA.
3)Click the service name and click on the "API specification" button.
4)Download the Specification, select the JSON option, since Service Studio supports creating services from JSON Swagger file specifications.
Note: To download the specification, you must sign in to your SAP account.
Now you can consume the webservice using the JSON specification in swagger to implement it in OutSystems.
When you have any questions about SAP OutSystems integration, when you feel you need a SAP OutSystems review or when you would like to talk about best practice for OutSystems Architecture, contact B-Synergy, OutSystems Partner with more than 10 years of OutSystems Experience.
