Business Events in SAP S/4HANA are triggered as part of some Business process example whenever a Sales Document is Created/Changed/Deleted. We all are familiar with Business Events since our ECC days since we would have used them in some of our developments.
In this Blog I will be only covering one flavor that is Business Event Handling in SAP S/4HANA Cloud since I could find many blogs on Enterprise Messaging and its integration with SAP S/4HANA Cloud but not on Business Event handling .Whereas sometimes your requirement can be fulfilled by business event handling too based on what you are looking for . So, you should be aware of both the flavors in Cloud as in Cloud currently we don't have released CDS views to check change pointers.
Two different eventing features in SAP S/4HANA Cloud are:
In this blog we will only cover how you can activate and use S/4HANA Cloud Business Events. For using SCP Service Enterprise Event Messaging; you need additional license for service Enterprise Messaging. Although many SAP blogs are available on how to configure Enterprise Messaging service but I would recommend to follow SAP help listed
here since it keeps evolving .Going forward Communication Arrangement for EMS in SAP S/4HANA Cloud will be created and updated via the Service Key of the EMS rather than creating manually in SAP S/4HANA Cloud .
Now let's see what all is required to use S/4HANA Cloud Business Events. Before you start using Business Event in SAP S/4HANA Cloud, please ensure
- Scope item 1NN is active
- Communication arrangement for scenario SAP_COM_0121 is in place
Once the prerequisite is in place; you just need to enable business events for objects you wish to use. Below 3 Fiori apps are key apps for configuring and using Business Events
Follow the listed steps:
- Create Subscriber Id: Go to Fiori app "Manage Your Solution" and check for Event Handling and select the below one

Then select "Create Subscriber Id" and configure - added BEVT as new Subscriber ID.

2. Enable the Subscription:Go to Fiori app "Business Event Subscription" and activate the Object type for which you want to enable the Business events. Example below I have activated event for Sales Order Create and Change.

3. Business Event Queue: Once the Business events are active for any object; same will be captured in Fiori app Business Event Queue.

Now you are good to use Business Events for Sales Order - any created /changed SO will be captured in the queue.
I am sure one question that will cross your mind would be
How can I find what all Business Events are Supported in S/4HANA Cloud?
You can check the same in Fiori app Business Event Subscription OR use the
link
Let's have a look at one of the use case where you can leverage Business events from SAP S/4HANA Cloud. In our example we want to display any created /changed sales Order in UI5 application as shown below.

Now you can read the events using OData C_BEHQUEUEDATA_CDS/C_Behqueuedata of Communication scenario SAP_COM_0121.Example you can use the postman to check the events that have been triggered in SAP S/4HANA Cloud system.

Summary: In this we have covered how you can read the business events queue and leverage Business events in SAP S/4HANA Cloud.
Before understanding Enterprise Messaging in Cloud , refer my blog
Discover SAP S/4HANA Cloud Extensibility Service in SCP for getting familiar with SAP S/4HANA Cloud Extensibility Service and how it can be used to automatically create Communication Arrangement in Cloud.
Regards,
Taranam