Lesson 19 Companion — RAP Business Events Reference

Start with the simple idea

When a customer creates an order, the Online Order application saves it. A RAP Business Event lets the application announce that the order was created. Other components can react to that announcement without being called directly by the Online Order application.

In Lesson 19, our separate component is a local warehouse listener. It reacts by writing a row to a log table. The business concept is more important than any one line of ABAP: a command asks for an action; an event reports an occurrence.

Create Order → Managed RAP Save → OrderCreated → Local Handler → Event Log

This reference is independent of Reservation, Support Issue and Checkpoint 4.

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1. Terms in one table

Term	Plain-language meaning	Our example
Command	Request to do something	Create an order
Business event	Announcement that something happened	OrderCreated
Producer	Component that announces it	Online Order RAP BO
Consumer	Component that responds	Local event handler
Event key	Which object it happened to	OrderUuid
Event payload	Additional useful details	ItemName
Local event handler	Event subscriber in the same system	ZCL_ORDER_EVT_###

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2. Object inventory

The manually created objects are:

ZPKG_L19_###           package
ZONLINESHOP_###        active order table
ZA_ORDER_EVT_###       abstract entity for event payload
ZORDEVT_###            consumer log table
ZCL_ORDER_EVT_###      local event handler class

The OData UI service generator creates the root CDS, base BDEF, Behavior Pool, projection, service, and possibly draft objects. Read their actual generated names; do not guess.

Reference generator-style names used in code examples:

ZR_ONLINESHOP_###       root CDS name
ZrOnlineshop###         root alias in BDEF
ZBP_R_ONLINESHOP_###    illustrative Behavior Pool

If ADT generates other names, substitute them consistently in BDEF, save_modified and handler signatures.

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3. The essential BDEF statements

Inside the base root behavior body:

event OrderCreated parameter ZA_Order_Evt_###;

In the global managed implementation header:

managed with additional save with full data
implementation in class zbp_r_onlineshop_### unique;
strict ( 2 );
with draft;

Retain other generated BDEF lines. Do not insert this managed header inside define behavior for ... { ... }.

If the generator produces a non-draft variant, preserve its actual valid configuration rather than copying a with draft; directive into a mismatched model.

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4. Why with additional save with full data?

managed: RAP supplies normal create/update/delete persistence.

with additional save: a custom saver method can run alongside that managed persistence.

with full data: the create-<alias> entries include business fields like Ordereditem, which we want to pass to the event without an additional read.

This is not the same as fully unmanaged RAP or with unmanaged save.

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5. The complete core producer snippet

In the saver class's generated save_modified method:

METHOD save_modified.

  IF create-zronlineshop### IS NOT INITIAL.

    RAISE ENTITY EVENT ZR_ONLINESHOP_###~OrderCreated
      FROM VALUE #(
        FOR new_order IN create-zronlineshop###
          ( %key            = new_order-%key
            %param-ItemName = new_order-Ordereditem )
      ).

  ENDIF.

ENDMETHOD.

This follows SAP's documented create-event implementation pattern. The root name in RAISE ENTITY EVENT is the globally unique CDS entity name. The create-zronlineshop### structure uses the generated alias.

In the current SAP tutorial, the create event is raised from the late save sequence, not inside the UI or the RAP create request itself.

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6. BDEF-derived event row type

RAISE ENTITY EVENT ... FROM expects data compatible with:

TYPE TABLE FOR EVENT ZR_ONLINESHOP_###~OrderCreated

You can supply a declared internal table or VALUE #( ... ) inline, as in the guided lesson.

Conceptual shape:

%key-OrderUuid
%param-ItemName

The consumer can read the same derived key and payload fields.

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7. Abstract entity: what it is and what it isn't

@EndUserText.label: 'Order Created Event Payload'
define abstract entity ZA_Order_Evt_###
{
  ItemName : abap.char(25);
}

It is: a reusable type description for the event's additional message data.

It isn't: an active order table, a service entity, or a database lookup.

Do not write SELECT FROM ZA_ORDER_EVT_###.

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8. Local event-handler class structure

Global class definition:

CLASS zcl_order_evt_### DEFINITION
  PUBLIC
  FINAL
  CREATE PUBLIC
  FOR EVENTS OF ZR_ONLINESHOP_###.
ENDCLASS.

CLASS zcl_order_evt_### IMPLEMENTATION.
ENDCLASS.

Local Types:

CLASS lcl_order_handler DEFINITION
  INHERITING FROM cl_abap_behavior_event_handler.

  PRIVATE SECTION.
    METHODS on_order_created
      FOR ENTITY EVENT
      IMPORTING created_orders
        FOR ZrOnlineshop###~OrderCreated.
ENDCLASS.

The global FOR EVENTS OF uses the root entity name; the local method's FOR ...~Event can use the alias. SAP's learning course explicitly documents this distinction.

An event-handler subclass may only declare a PRIVATE SECTION. IMPORTING is required conceptually even for a key-only event; with this syntax we spell it out explicitly.

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9. Complete local handler implementation

CLASS lcl_order_handler IMPLEMENTATION.

  METHOD on_order_created.

    cl_abap_tx=>save( ).

    LOOP AT created_orders ASSIGNING FIELD-SYMBOL(<event>).

      DATA log_entry TYPE zordevt_###.
      CLEAR log_entry.

      log_entry-order_uuid = <event>-%key-OrderUuid.
      log_entry-item_name = <event>-%param-ItemName.
      GET TIME STAMP FIELD log_entry-received_at.

      MODIFY zordevt_### FROM @log_entry.

    ENDLOOP.

  ENDMETHOD.

ENDCLASS.

This is an asynchronous consumer running in its own context, not an ordinary class method called by the producer. SAP's September 2026 tutorial calls CL_ABAP_TX=>SAVE( ) before writing directly to an independent log table to close the active RAP modify phase.

MODIFY makes the demo one-log-entry-per-order: if the same event is handled again, the same key is updated rather than creating another row. For production systems, treat retries, error logging and event idempotence explicitly.

No COMMIT WORK is added.

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10. The two tables have different owners

ZONLINESHOP_### → RAP-managed business persistence
ZORDEVT_###     → separate local-consumer demo log

The event handler may write to its own log table. It should not bypass RAP by modifying ZONLINESHOP_### directly.

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11. What we verify in Data Preview

Test	ZONLINESHOP_###	ZORDEVT_###
Draft created, not activated	No new active row	No new receipt
New order activated	New active row	Receipt eventually appears
Existing order updated	Existing row changes	No new OrderCreated receipt
Display/read only	No new active row	No new receipt

The active order UUID and event log UUID should match.

Note: the order created before event activation is not retroactively published.

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12. Why not use %control in this lesson?

We detect create, not a transition such as Status N → C.

The additional-save create-<alias> table tells us which new instances were created. No comparison of an old and new status is needed, and we do not need a %control-Status condition.

This makes Business Events easier to introduce than the previous Reservation Confirm scenario.

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13. Draft: one sentence to remember

Draft editing is not the final business operation. With the generated Draft application, Save/Activate is the point to check active order persistence and the event's processing.

TABLE FOR EVENT types do not expose %is_draft or %tky; those are not a way to publish events for draft instances.

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14. Local vs remote consumption

Local:

Same ABAP system
RAP producer → local event-handler class

Remote:

RAP producer → Event Binding → event infrastructure → remote subscriber

Event Binding is not Service Binding. The first is for remote event publication; the latter exposes OData APIs.

Remote consumption and Event Mesh provisioning are not mandatory for this lesson.

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15. Release-contract nuance

SAP recommends stable, released interfaces for reusable integration APIs and supports C1/C2 release concepts. The official RAP Learning examples and the September 2026 Online Shop tutorial also show a local event handler connected directly to the custom RAP root inside a teaching setup.

Do not turn C1 release into a prerequisite for this basic local demonstration. Production interface release and compatibility are a later Clean Core concern.

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16. When would a real company use this?

Possible follow-ups to OrderCreated:

• inform a warehouse fulfillment system;
• initiate a notification workflow;
• update a downstream analytics model;
• begin delivery planning.

The Online Order provider should not have to import and call each consumer's code directly.

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17. Failure investigation

Symptom	Likely layer
Order isn't saved	Generated RAP app / Draft / service
No save_modified	Additional-save header or saver generation
Event table empty	create-<alias> and save sequence
Event raised but no log	Handler activation, delivery, consumer errors
Handler enters but direct SQL fails	CL_ABAP_TX=>SAVE( ), table access, key mapping
ItemName blank	Abstract entity, %param mapping
Syntax complains about event name	Global CDS entity name vs alias

SAP runtime tools and authorizations differ among shared Trial instances. Record the actual error rather than telling students to keep rebuilding objects.

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18. Code review checklist

• The application is a new standalone package.
• Root/alias names match generated objects.
• Event declared inside base BDEF root body.
• Additional save appears in the global managed implementation header.
• Saver generated by Quick Fix.
• RAISE ENTITY EVENT is in save_modified.
• %key comes from the newly created order.
• %param-ItemName comes from Ordereditem.
• Global handler uses FOR EVENTS OF.
• Local handler has only PRIVATE SECTION.
• Consumer uses CL_ABAP_TX=>SAVE( ) before log SQL.
• Logs are observable independently from active orders.
• Nobody modified earlier course objects.

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19. Primary SAP references

• Create a RAP Business Event in SAP BTP ABAP Environment — standalone Online Shop generator, full-data additional save and a local event handler; revised September 2026.
• Raising and Handling Business Events — RAP business events and local handling.
• Working with Event Parameters — abstract entities, %key and %param.
• RAP110 Exercise 11 — alternate SAP workshop implementation.

Scope of validation: patterns compared against published SAP examples. Runtime activation and asynchronous event delivery remain to be checked in the actual instructor/student ABAP environment.