sap-rap-gen

name	sap-rap-gen
description	Generate complete SAP RAP business objects — BDEF, behavior implementation, CDS views, service definition, service binding. Managed/unmanaged, draft-enabled, custom entities.
trigger	{"keywords":["generate rap","rap business object","behavior definition","bdef","cds view entity","rap service","draft enabled bo","restful application programming model"],"intent":"Generate complete SAP RAP business objects with BDEF, behavior implementation, CDS views, and service bindings.","patterns":["generate.*rap.*bo","create.*behavior definition","scaffold.*rap","rap.*managed.*implementation"]}

SAP RAP Generator

RAP = CDS data model + behavior definition + behavior implementation + service exposure. One root entity per BO. Compositions link child nodes. Managed = runtime handles CRUD automatically.

Prerequisites

• ABAP 7.57+ (Cloud or on-premise S/4HANA 2020+); ADT with RAP support
• Authorization to create DDIC tables, CDS views, BDEF, classes, service definitions
• Existing persistent table (e.g. ZPRODUCT) with key fields

Architecture (generate in this order)

ZPRODUCT (DB table)
  └─ Z_I_PRODUCT   → CDS View Entity (data model, root)
  └─ Z_R_PRODUCT   → Behavior Definition (transactional contract)
  └─ ZBP_I_PRODUCT → Behavior Implementation (ABAP class)
  └─ Z_C_PRODUCT   → CDS Projection (consumption layer)
  └─ Z_SRV_PRODUCT → Service Definition + Binding (OData V4)
  └─ Z_D_PRODUCT   → Draft table (only if draft-enabled)

Step 1 — CDS View Entity

@AccessControl.authorizationCheck: #CHECK
@EndUserText.label: 'Product Master Data'
@ObjectModel.semanticKey: ['Material']
define view entity Z_I_PRODUCT
  as select from zproduct
  composition [0..*] of Z_I_STOCK as _Stock
{
  key product_guid    as ProductGuid,
      material        as Material,
      @ObjectModel.mandatory: true
      material_type   as MaterialType,
      @Search.defaultSearchElement: true
      description     as Description,
      plant           as Plant,
      @Semantics.systemDate.createdAt: true
      created_at      as CreatedAt,
      @Semantics.systemDate.lastChangedAt: true
      last_changed_at as LastChangedAt,
      _Stock
}

Step 2 — Behavior Definition (Managed + Draft)

managed implementation in class zbp_i_product unique;
strict(2);

define behavior for z_i_product alias Product
persistent table zproduct
draft table z_d_product
lock master total etag last_changed_at
authorization master ( instance )
etag master last_changed_at
{
  create;
  update;
  delete;

  field (mandatory) material_type, description;
  field (readonly) product_guid, created_at;
  field (readonly:update) material;

  determination set_audit_fields on modify { create; update; }

  mapping for zproduct {
    product_guid = product_guid; material = material;
    material_type = material_type; description = description;
    plant = plant; created_at = created_at;
    last_changed_at = last_changed_at;
  }
}

Step 3 — Behavior Implementation

CLASS lhc_product DEFINITION INHERITING FROM cl_abap_behavior_handler.
  PRIVATE SECTION.
    METHODS set_audit_fields FOR DETERMINE ON MODIFY
      IMPORTING keys FOR product~set_audit_fields.
ENDCLASS.

CLASS lhc_product IMPLEMENTATION.
  METHOD set_audit_fields.
    READ ENTITIES OF z_i_product IN LOCAL MODE
      ENTITY product FIELDS ( created_at last_changed_at )
      WITH CORRESPONDING #( keys )
      RESULT DATA(lt_products).

    MODIFY ENTITIES OF z_i_product IN LOCAL MODE
      ENTITY product UPDATE FIELDS ( created_at last_changed_at )
      WITH VALUE #( FOR ls IN lt_products (
        %tky = ls-%tky
        created_at = COND #( WHEN ls-created_at IS INITIAL
                             THEN utclong_current( ) ELSE ls-created_at )
        last_changed_at = utclong_current( ) ) ).
  ENDMETHOD.
ENDCLASS.

Step 4 — Projection View

@AccessControl.authorizationCheck: #CHECK
@Metadata.allowExtensions: true
define root view entity Z_C_PRODUCT as projection on Z_I_PRODUCT
{
  key ProductGuid, Material, MaterialType, Description,
      Plant, CreatedAt, LastChangedAt,
      _Stock : redirected to Z_C_STOCK
}

Step 5 — Service Definition + Binding

@EndUserText.label: 'Product Service'
define service Z_SRV_PRODUCT { expose Z_C_PRODUCT as Product; }

Bind: right-click service definition → New Service Binding → OData V4 - UI → Activate.

Managed vs Unmanaged

• Managed: runtime auto-implements CRUD, draft, locking, ETag. Use for greenfield tables.
• Unmanaged: you write READ, CREATE, UPDATE, DELETE, SAVE. Use for legacy tables, external APIs, multi-table LUWs.

Quick Commands

# Trigger generation (skill auto-activates)
"generate RAP BO for Product with fields: product_guid(UUID,key), material(CHAR18), description(CHAR40), draft enabled"

# Check existing BDEF
aibap: get_object_info(name="Z_I_PRODUCT")

# Activate all generated objects (dependency order)
aibap: activate_objects(["Z_I_PRODUCT","Z_C_PRODUCT","Z_R_PRODUCT","ZBP_I_PRODUCT","Z_SRV_PRODUCT"])

# Run unit tests on behavior implementation
aibap: run_unit_tests(["ZBP_I_PRODUCT"])

Pitfalls

• BDEF name = CDS view name — linked automatically at activation, no manual mapping.
• strict(2) requires S/4HANA 2021+; use strict(1) for 2020 compat.
• Draft table: must match active table fields + draft-specific columns (mandt, draftentityoperationcode). Generate via ADT "Generate Draft Table".
• MAPPING clause: required when CDS aliases differ from DB column names; omit only if identical.
• Projection view: must redirect compositions via : redirected to — missing redirect breaks activation.
• Service binding: OData V4 - UI for Fiori Elements, OData V4 - API for programmatic.
• Late numbering: managed BOs with UUID keys use late numbering — keys assigned in save sequence.
• Never use READ ENTITIES outside IN LOCAL MODE inside determinations — breaks transactional buffer.
• Never call COMMIT ENTITIES from within a determination or validation method.

Verification

" 1. Activate in order: Table → CDS → BDEF → Impl → Projection → Svc Def → Svc Binding
" 2. Preview service binding → OData $metadata must list entity + draft actions
" 3. Test draft flow: Create → Edit → Save → Verify active record in ZPRODUCT
" 4. Run behavior unit tests: aibap: run_unit_tests(["ZBP_I_PRODUCT"])
" 5. Verify ETag: LastChangedAt must update on each modify

Custom Entity (query-only, no persistence)

@ObjectModel.query.implementedBy: 'ABAP:ZCL_CUSTOM_QUERY'
define custom entity Z_C_CUSTOM_SEARCH {
  key search_id : sysuuid_x16; search_term : string; result_count : int4;
}