Service Definition and Service Binding

Service Definition — What to Expose

The service definition lists which entities from your projection are available via OData:

In ADT: Right-click package → New → Service Definition

@EndUserText.label: 'TechMart Sales Order Service'
define service ZSD_TM_SALESORDER {
  expose ZC_TM_SalesOrder as SalesOrder;
  expose ZC_TM_SalesOrderItem as SalesOrderItem;
  expose ZI_TM_Customer as Customer;
  expose ZI_TM_Product as Product;
}

You expose projection views (for transactional entities) and interface views (for reference data like Customer and Product). The as alias becomes the entity set name in OData.

Service Binding — How to Expose

The service binding connects the definition to a protocol:

In ADT: Right-click package → New → Service Binding

• Name: ZSB_TM_SALESORDER_V4
• Binding Type: OData V4 - UI
• Service Definition: ZSD_TM_SALESORDER

After activation, click Publish in the service binding editor. This registers the OData service.

Then click Preview next to the SalesOrder entity set. ADT launches a browser with a fully functional Fiori Elements list report + object page — generated entirely from your CDS annotations.

┌─────────────────────────────────────────────────────┐
│  Sales Orders                          [Create] [⋮]  │
├─────────────────────────────────────────────────────┤
│  Filters: [Customer ID ▾] [Status ▾]    [Go]  [▾]  │
├──────┬──────────┬────────┬───────────┬──────────────┤
│ ID   │ Customer │ Date   │ Status    │ Total Amount │
├──────┼──────────┼────────┼───────────┼──────────────┤
│ 1001 │ CUST-42  │ Jan 15 │ New       │ 5,499.99 USD │
│ 1002 │ CUST-07  │ Mar 20 │ Completed │ 24,000.00 USD│
└──────┴──────────┴────────┴───────────┴──────────────┘

You can create, edit, and delete orders right from this preview. No frontend code written.

OData V2 vs V4

Default to OData V4 for all new development.

Key Takeaways

• Service definition lists WHICH entities to expose. Service binding defines HOW (OData V2/V4).
• Fiori Elements preview generates a complete UI from CDS annotations — no frontend code.
• Default to OData V4 for new apps.
• Publish the service binding after activation.
• The Fiori preview is your primary testing tool during RAP development.

Next Lesson

The Fiori preview lets users interact with data through the UI. But sometimes you need to manipulate business objects programmatically — in background jobs, integrations, or custom logic. In Lesson 16, we'll learn EML (Entity Manipulation Language) — the ABAP way to read, create, update, and delete RAP business objects from code.