OData Service Development

Guide for creating and consuming OData services in ABAP, covering both RAP-based (V4/V2) and SEGW-based (V2) approaches.

Workflow

1. Determine the user's goal:

- Exposing a RAP BO as an OData service (recommended approach) - Creating a classic SEGW-based OData V2 service - Consuming an external OData service from ABAP - Adding OData annotations for Fiori UIs - Troubleshooting OData errors

1. Identify the approach:

- RAP-based service (preferred for ABAP Cloud) - SEGW-based service (classic, Standard ABAP only) - OData consumption (client proxy)

1. Guide implementation following SAP best practices

RAP-Based OData Services (Recommended)

Architecture Flow

CDS View Entity → Behavior Definition → Service Definition → Service Binding
                                                                    ↓
                                                              OData V4/V2 Endpoint

Service Definition

Exposes CDS entities and their behaviors as a named service:

@EndUserText.label: 'Travel Service'
define service ZUI_TRAVEL_O4 {
  expose ZC_Travel as Travel;
  expose ZC_Booking as Booking;
  expose I_Currency as Currency;
  expose I_Country as Country;
}

Key Rules

• Expose projection CDS views (C\_ prefix by convention), not root views
• Include value help CDS views (I\_\* views) the UI needs
• Alias names become OData entity set names
• One service definition can be bound to multiple protocols

Service Binding

Binds a service definition to a specific OData protocol and provides a URL:

Creating a Service Binding

1. In ADT: New → Other ABAP Repository Object → Business Services → Service Binding
2. Select the service definition
3. Choose binding type (e.g., OData V4 - UI)
4. Activate
5. Click Publish to register the service
6. Click Preview to open the Fiori Elements preview

OData V4 vs V2

SEGW-Based OData V2 Services (Classic)

For Standard ABAP only (not available in ABAP Cloud):

Architecture

SEGW Project → Data Model (Entity Types, Sets, Associations)
             → Service Implementation (MPC/DPC classes)
             → Register & Activate in /IWFND/MAINT_SERVICE

Steps

1. Create project in SEGW transaction
2. Define data model: Entity types, properties, navigation properties
3. Generate runtime artifacts (MPC/DPC classes)
4. Implement DPC extension methods: GETENTITYSET, GETENTITY, CREATE_ENTITY, etc.
5. Register service in /IWFND/MAINT_SERVICE
6. Test via /IWFND/GW_CLIENT or browser

DPC Method Implementation Example

METHOD travelset_get_entityset.
  SELECT * FROM ztravel_tab
    INTO TABLE @DATA(lt_travel)
    UP TO 100 ROWS.

  et_entityset = CORRESPONDING #( lt_travel ).
ENDMETHOD.

Consuming External OData Services

In ABAP Cloud (using HTTP Client and Communication Arrangements)

"1. Get HTTP client via communication arrangement
DATA(lo_dest) = cl_http_destination_provider=>create_by_comm_arrangement(
  comm_scenario  = 'Z_MY_OUTBOUND_SCENARIO'
  service_id     = 'Z_MY_HTTP_SERVICE' ).

DATA(lo_client) = cl_web_http_client_manager=>create_by_http_destination( lo_dest ).

"2. Build request
DATA(lo_request) = lo_client->get_http_request( ).
lo_request->set_uri_path( '/sap/opu/odata4/sap/api_business_partner/srvd_a2x/sap/api_business_partner/0001/A_BusinessPartner?$top=10' ).

"3. Execute and parse response
DATA(lo_response) = lo_client->execute( if_web_http_client=>get ).
DATA(lv_json) = lo_response->get_text( ).
lo_client->close( ).

Using OData Client Proxy (V2/V4)

"Create OData client proxy for V4
DATA(lo_proxy) = /iwbep/cl_cp_client_proxy_fact=>create_v4_remote_proxy(
  iv_service_definition_name = 'Z_MY_ODATA_CDEF'
  io_http_client             = lo_client
  iv_relative_service_root   = '/sap/opu/odata4/sap/api_service/0001/' ).

"Build and execute read request
DATA(lo_request) = lo_proxy->create_resource_for_entity_set( 'ENTITYSETNAME' )->create_request_for_read( ).
lo_request->set_top( 10 ).
DATA(lo_response) = lo_request->execute( ).

"Get business data
DATA lt_data TYPE STANDARD TABLE OF z_entity_type.
lo_response->get_business_data( IMPORTING et_business_data = lt_data ).

OData Annotations for Fiori

Key CDS annotations that control OData/Fiori behavior:

@UI.headerInfo: {
  typeName: 'Travel',
  typeNamePlural: 'Travels',
  title: { type: #STANDARD, value: 'TravelID' },
  description: { type: #STANDARD, value: 'Description' }
}

@UI.lineItem: [{ position: 10 }]
@UI.selectionField: [{ position: 10 }]
@UI.identification: [{ position: 10 }]
TravelID;

@UI.lineItem: [{ position: 20, importance: #HIGH }]
@UI.identification: [{ position: 20 }]
@Consumption.valueHelpDefinition: [{ entity: { name: 'I_Currency', element: 'Currency' } }]
CurrencyCode;

Troubleshooting

Output Format

When helping with OData topics, structure responses as:

## OData Service Guidance

### Approach

- Type: [RAP-based / SEGW-based / Consumption]
- Protocol: [OData V4 / OData V2]

### Implementation

[Step-by-step with code examples]

### Testing

[How to test the service]

References

• SAP OData V4 Documentation: https://help.sap.com/docs/abap-cloud/abap-rap/odata-service
• RAP Service Binding: https://help.sap.com/docs/abap-cloud/abap-rap/service-binding
• OData Client Proxy: https://help.sap.com/docs/abap-cloud/abap-rap/odata-client-proxy