odata-abap

name	odata-abap
description	OData service development in ABAP — CDS-exposed OData, SADL service definitions, RAP service bindings, SEGW legacy, OData V2/V4, query options, deep insert, ETag, batch, service registration. Use when creating OData services, exposing CDS views, or troubleshooting SAP Gateway errors.
trigger	odata abap, @OData.publish, service binding, service definition, /IWFND/MAINT_SERVICE, SEGW, SADL, OData V4 ABAP, RAP unmanaged, DPC_EXT, $metadata, deep insert, ETag

OData Service Development in ABAP

Three approaches: CDS-exposed (simplest), Service Definition + Binding (RAP, recommended), SEGW (legacy).

Prerequisites

• SAP system with SAP Gateway (SAP_GWFND) or S/4HANA
• ABAP Development Tools (ADT) in Eclipse
• Development package and transport request
• Authorization for /IWFND/MAINT_SERVICE

1. CDS-Exposed OData (Simplest)

@OData.publish: true
@EndUserText.label: 'Product API'
define view entity Z_C_PRODUCT_API
  as select from zproduct
{
  key product_guid  as ProductGuid,
      material      as Material,
      material_type as MaterialType,
      description   as Description,
      created_at    as CreatedAt,

      @Consumption.filter: { mandatory: false }
      plant          as Plant
}

1. Activate the CDS view in ADT
2. OData service auto-registers as Z_C_PRODUCT_API_CDS
3. Register in Gateway: /IWFND/MAINT_SERVICE → Add Service
4. Test via SAP Gateway Client (/IWFND/GW_CLIENT)

2. Service Definition + Binding (RAP — Recommended)

Service Definition (SRVD):

@EndUserText.label: 'Product Service'
define service Z_PRODUCT_SRV {
  expose Z_C_PRODUCT_API      as Product;
  expose Z_C_PRODUCT_TEXT_API as ProductText;
}

Service Binding (SRVB) in ADT:

1. Right-click service definition → New → Service Binding
2. Binding type: OData V4 (UI)
3. Select service definition: Z_PRODUCT_SRV
4. Activate → click Preview to test

3. SEGW Manual OData (Legacy)

SEGW → Create Project → Data Model
  Entity: Product
    Properties: ProductGuid (Edm.Guid, Key), Material (Edm.String)
  Generate runtime artifacts → DPC_EXT class

DPC_EXT implementation:

METHOD products_get_entity.
  DATA(lv_guid) = io_tech_request_context->get_converted_keys(
    )->get_value( 'PRODUCTGUID' ).
  SELECT SINGLE * FROM zproduct
    WHERE product_guid = @lv_guid
    INTO CORRESPONDING FIELDS OF @er_entity.
ENDMETHOD.

4. Query Options

• $filter: Material eq 'MAT001'
• $expand: $expand=ProductText
• $orderby: $orderby=CreatedAt desc
• $top/$skip: $top=10&$skip=20
• $select: $select=Material,Description
• $count: $count=true (V2) / $count path segment (V4)

5. Deep Insert (Parent + Children)

POST /sap/opu/odata/sap/Z_PRODUCT_SRV/Product
Content-Type: application/json

{
  "Material": "MAT001",
  "Description": "Test Product",
  "to_ProductText": [
    { "Language": "EN", "Description": "English text" },
    { "Language": "DE", "Description": "German text" }
  ]
}

6. ETag (Optimistic Locking)

@Semantics.systemDate.lastChangedAt: true
created_at as LastChangedAt

Client sends If-Match: <etag> header. Server returns 412 Precondition Failed if record changed.

7. Batch Operations

POST /sap/opu/odata/sap/Z_PRODUCT_SRV/$batch
Content-Type: multipart/mixed; boundary=batch_boundary

--batch_boundary
Content-Type: application/http

GET Product('ABC123') HTTP/1.1

--batch_boundary
Content-Type: application/http

POST Product HTTP/1.1
Content-Type: application/json

{"Material":"MAT002","Description":"Batch created"}

--batch_boundary--

8. Service Registration (/IWFND/MAINT_SERVICE)

1. Transaction /IWFND/MAINT_SERVICE
2. Add Service → System Alias: LOCAL
3. Technical Service Name: Z_PRODUCT_SRV (or Z_C_PRODUCT_API_CDS)
4. Service Version: 0001
5. Add → OK → Back → Load Metadata

Pitfalls

• $filter on Edm.Guid fails — Cause: GUIDs need special syntax. Solution: use ProductGuid eq guid'xxxx-xxxx-...' (V2) or ProductGuid eq xxxxxxxx-xxxx-... without quotes (V4).

• Service not visible after activation — Cause: CDS view activated but Gateway cache stale. Solution: run /IWFND/CACHE_CLEANUP or /IWFND/MED_CLEANUP to clear metadata cache.

• $expand returns empty — Cause: navigation property not defined or association cardinality mismatch. Solution: verify association in CDS view and that the target entity is also exposed in the same service.

• SEGW generates code but 500 error — Cause: DPC_EXT method not redefined or super-> call missing. Solution: redefine method in Z-class, not base class; call super-> for unhandled entities.

• OData V2 vs V4 mismatch — Cause: V4 uses different query syntax ($count path vs $count=true). Solution: check service binding type; V4 doesn't support $inlinecount.

• Draft-enabled entity not editable — Cause: draft actions not exposed or @ObjectModel.draftEnabled: true missing. Solution: add @ObjectModel.draftEnabled: true to CDS view and activate.

Verification

# 1. Check $metadata loads
curl -u <user>:<pass> \
  "https://<host>/sap/opu/odata/sap/Z_PRODUCT_SRV/\$metadata"

# 2. Query entity set
curl -u <user>:<pass> \
  "https://<host>/sap/opu/odata/sap/Z_PRODUCT_SRV/Product?\$top=5"

# 3. Verify in SAP Gateway Client (/IWFND/GW_CLIENT)
#    GET /sap/opu/odata/sap/Z_PRODUCT_SRV/$metadata  → expect 200

# 4. Check service is registered
#    /IWFND/MAINT_SERVICE → search Z_PRODUCT_SRV → Status: green

# 5. Test deep insert
curl -X POST -H "Content-Type: application/json" \
  -d '{"Material":"TEST","to_ProductText":[]}' \
  "https://<host>/sap/opu/odata/sap/Z_PRODUCT_SRV/Product"