RAP Actions and Functions: Implementing Business Logic

Action vs. Function: The Difference

Aspect	Action	Function
Purpose	Modifies data (side effects)	Reads/calculates data (no side effects)
HTTP Method	POST	GET
Transactional	Yes, part of the transaction	No, read-only
Idempotent	No	Yes
Examples	Cancel, Release, Copy	Calculate price, Check availability

When to Use Action vs. Function?

Action: When the operation changes the state of the entity or system
Function: When only a value is calculated or information is retrieved without changing data

Bound vs. Unbound (Static)

Aspect	Bound (Instance)	Unbound (Static)
Context	Bound to an instance	Without instance context
Invocation	On selected row	Via button in toolbar
Keys	Instance keys available	No automatic keys
Use Case	”Cancel this travel"	"Release all open travels”

Instance-bound Action

An instance-bound action is executed on a specific instance:

Behavior Definition

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

define behavior for ZI_Travel alias Travel
persistent table ztravel
lock master
authorization master ( instance )
{
  // Instance-bound Action without parameters
  action cancel result [1] $self;

  // Instance-bound Action with result
  action accept result [1] $self;

  // Instance-bound Action returning multiple instances
  action copyTravel result [0..*] $self;
}

Implementation

CLASS lhc_travel DEFINITION INHERITING FROM cl_abap_behavior_handler.
  PRIVATE SECTION.
    METHODS cancel FOR MODIFY
      IMPORTING keys FOR ACTION Travel~cancel RESULT result.

    METHODS accept FOR MODIFY
      IMPORTING keys FOR ACTION Travel~accept RESULT result.
ENDCLASS.

CLASS lhc_travel IMPLEMENTATION.
  METHOD cancel.
    " Read current data
    READ ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        FIELDS ( TravelID Status )
        WITH CORRESPONDING #( keys )
      RESULT DATA(travels).

    " Only open travels can be cancelled
    LOOP AT travels ASSIGNING FIELD-SYMBOL(<travel>)
      WHERE Status = 'O'.

      " Set status to Cancelled
      MODIFY ENTITIES OF zi_travel IN LOCAL MODE
        ENTITY Travel
          UPDATE FIELDS ( Status )
          WITH VALUE #( (
            %tky   = <travel>-%tky
            Status = 'X'  " Cancelled
          ) ).
    ENDLOOP.

    " Return result
    READ ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        ALL FIELDS
        WITH CORRESPONDING #( keys )
      RESULT DATA(travels_result).

    result = VALUE #( FOR travel IN travels_result (
      %tky   = travel-%tky
      %param = travel
    ) ).
  ENDMETHOD.

  METHOD accept.
    " Set status to Accepted
    MODIFY ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        UPDATE FIELDS ( Status )
        WITH VALUE #( FOR key IN keys (
          %tky   = key-%tky
          Status = 'A'  " Accepted
        ) ).

    " Return updated data
    READ ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        ALL FIELDS
        WITH CORRESPONDING #( keys )
      RESULT DATA(travels).

    result = VALUE #( FOR travel IN travels (
      %tky   = travel-%tky
      %param = travel
    ) ).
  ENDMETHOD.
ENDCLASS.

Result Cardinality

Cardinality	Meaning
`result [1] $self`	Exactly one instance returned (the same entity)
`result [0..1] $self`	Optionally one instance
`result [0..*] $self`	Any number of instances
`result [1] EntityName`	One instance of a different entity
(no result)	No return value

Static (Unbound) Action

Static actions are not bound to an instance and are typically used for mass operations:

Behavior Definition

define behavior for ZI_Travel alias Travel
{
  // Static Action without parameters
  static action releaseAllOpen;

  // Static Action with result
  static action createFromTemplate result [1] $self;

  // Static Action with Global Feature Control
  static action ( features: global ) massUpdate;

  // For Global Feature Control
  static features;
}

Implementation

CLASS lhc_travel DEFINITION INHERITING FROM cl_abap_behavior_handler.
  PRIVATE SECTION.
    METHODS releaseAllOpen FOR MODIFY
      IMPORTING keys FOR ACTION Travel~releaseAllOpen.

    METHODS createFromTemplate FOR MODIFY
      IMPORTING keys FOR ACTION Travel~createFromTemplate RESULT result.

    METHODS get_global_features FOR GLOBAL FEATURES
      IMPORTING REQUEST requested_features FOR Travel RESULT result.
ENDCLASS.

CLASS lhc_travel IMPLEMENTATION.
  METHOD releaseAllOpen.
    " Find all open travels
    SELECT * FROM ztravel
      WHERE status = 'O'
      INTO TABLE @DATA(open_travels).

    " Set status to Released
    MODIFY ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        UPDATE FIELDS ( Status )
        WITH VALUE #( FOR travel IN open_travels (
          TravelUUID = travel-travel_uuid
          Status     = 'R'  " Released
        ) ).
  ENDMETHOD.

  METHOD createFromTemplate.
    " Create new travel from template
    DATA(template_id) = 'DEFAULT'.

    " Load template (simplified example)
    SELECT SINGLE * FROM ztravel_template
      WHERE template_id = @template_id
      INTO @DATA(template).

    " Create new travel
    MODIFY ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        CREATE FIELDS ( CustomerID BeginDate EndDate Description )
        WITH VALUE #( (
          %cid        = 'NEW_TRAVEL'
          CustomerID  = template-customer_id
          BeginDate   = cl_abap_context_info=>get_system_date( )
          EndDate     = cl_abap_context_info=>get_system_date( ) + 7
          Description = 'Created from template'
        ) )
      MAPPED DATA(mapped).

    " Return created entity
    READ ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        ALL FIELDS
        WITH VALUE #( ( %tky = mapped-travel[ 1 ]-%tky ) )
      RESULT DATA(created_travel).

    result = VALUE #( (
      %cid_ref = 'NEW_TRAVEL'
      %param   = created_travel[ 1 ]
    ) ).
  ENDMETHOD.

  METHOD get_global_features.
    " Check if user has authorization for mass update
    DATA(has_auth) = check_mass_update_auth( ).

    result = VALUE #(
      %action-massUpdate = COND #(
        WHEN has_auth = abap_true
        THEN if_abap_behv=>fc-o-enabled
        ELSE if_abap_behv=>fc-o-disabled )
    ).
  ENDMETHOD.
ENDCLASS.

Function: Calculations Without Side Effects

Functions are ideal for calculations and queries that do not change data:

Behavior Definition

define behavior for ZI_Travel alias Travel
{
  // Instance-bound Function
  function calculatePrice result [1] ZA_Price;

  // Function with multiple return values
  function getAvailability result [1] ZA_Availability;

  // Static Function
  static function getExchangeRates result [0..*] ZA_ExchangeRate;

  // Function with parameters
  function simulateDiscount
    parameter ZA_DiscountInput
    result [1] ZA_DiscountResult;
}

Abstract Entity for Return Values

Functions often require abstract entities for structured return values:

define abstract entity ZA_Price
{
  TravelUUID : sysuuid_x16;
  NetPrice   : abap.dec( 15, 2 );
  TaxAmount  : abap.dec( 15, 2 );
  TotalPrice : abap.dec( 15, 2 );
  Currency   : abap.cuky;
}

define abstract entity ZA_Availability
{
  TravelUUID   : sysuuid_x16;
  IsAvailable  : abap_boolean;
  SeatsLeft    : abap.int4;
  NextAvailable: abap.dats;
}

Implementation

CLASS lhc_travel DEFINITION INHERITING FROM cl_abap_behavior_handler.
  PRIVATE SECTION.
    METHODS calculatePrice FOR READ
      IMPORTING keys FOR FUNCTION Travel~calculatePrice RESULT result.

    METHODS getAvailability FOR READ
      IMPORTING keys FOR FUNCTION Travel~getAvailability RESULT result.

    METHODS getExchangeRates FOR READ
      IMPORTING keys FOR FUNCTION Travel~getExchangeRates RESULT result.
ENDCLASS.

CLASS lhc_travel IMPLEMENTATION.
  METHOD calculatePrice.
    " Read travel data
    READ ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        FIELDS ( TotalPrice Currency )
        WITH CORRESPONDING #( keys )
      RESULT DATA(travels).

    LOOP AT travels ASSIGNING FIELD-SYMBOL(<travel>).
      " Calculate price (simplified)
      DATA(net_price) = <travel>-TotalPrice * '0.84'.
      DATA(tax_amount) = <travel>-TotalPrice * '0.16'.

      APPEND VALUE #(
        %tky = <travel>-%tky
        %param = VALUE za_price(
          TravelUUID = <travel>-TravelUUID
          NetPrice   = net_price
          TaxAmount  = tax_amount
          TotalPrice = <travel>-TotalPrice
          Currency   = <travel>-Currency
        )
      ) TO result.
    ENDLOOP.
  ENDMETHOD.

  METHOD getAvailability.
    READ ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        FIELDS ( BeginDate MaxSeats BookedSeats )
        WITH CORRESPONDING #( keys )
      RESULT DATA(travels).

    LOOP AT travels ASSIGNING FIELD-SYMBOL(<travel>).
      DATA(seats_left) = <travel>-MaxSeats - <travel>-BookedSeats.

      APPEND VALUE #(
        %tky = <travel>-%tky
        %param = VALUE za_availability(
          TravelUUID    = <travel>-TravelUUID
          IsAvailable   = COND #( WHEN seats_left > 0 THEN abap_true ELSE abap_false )
          SeatsLeft     = seats_left
          NextAvailable = COND #( WHEN seats_left = 0
                                  THEN <travel>-BeginDate + 30
                                  ELSE <travel>-BeginDate )
        )
      ) TO result.
    ENDLOOP.
  ENDMETHOD.

  METHOD getExchangeRates.
    " Static Function - no keys available
    " Read exchange rates from system
    SELECT * FROM tcurr
      WHERE kurst = 'M'
        AND gdatu >= @( cl_abap_context_info=>get_system_date( ) )
      INTO TABLE @DATA(rates)
      UP TO 100 ROWS.

    result = VALUE #( FOR rate IN rates (
      %param = VALUE za_exchangerate(
        SourceCurrency = rate-fcurr
        TargetCurrency = rate-tcurr
        ExchangeRate   = rate-ukurs
        ValidFrom      = rate-gdatu
      )
    ) ).
  ENDMETHOD.
ENDCLASS.

Action with Input Parameters

Actions can accept structured input parameters:

Behavior Definition

define behavior for ZI_Travel alias Travel
{
  // Action with abstract parameter
  action rejectWithReason
    parameter ZA_RejectionReason
    result [1] $self;

  // Action with multiple parameters
  action reschedule
    parameter ZA_RescheduleInput
    result [1] $self;

  // Action with Deep Structure
  action addParticipants
    parameter ZA_ParticipantList
    result [1] $self;
}

Abstract Entity for Input Parameters

define abstract entity ZA_RejectionReason
{
  ReasonCode : abap.char( 2 );
  ReasonText : abap.string( 255 );
  NotifyCustomer : abap_boolean;
}

define abstract entity ZA_RescheduleInput
{
  NewBeginDate : abap.dats;
  NewEndDate   : abap.dats;
  UpdatePrice  : abap_boolean;
}

Implementation

CLASS lhc_travel DEFINITION INHERITING FROM cl_abap_behavior_handler.
  PRIVATE SECTION.
    METHODS rejectWithReason FOR MODIFY
      IMPORTING keys FOR ACTION Travel~rejectWithReason RESULT result.

    METHODS reschedule FOR MODIFY
      IMPORTING keys FOR ACTION Travel~reschedule RESULT result.
ENDCLASS.

CLASS lhc_travel IMPLEMENTATION.
  METHOD rejectWithReason.
    " Read parameters from keys
    LOOP AT keys ASSIGNING FIELD-SYMBOL(<key>).
      " Rejection reason from parameter
      DATA(reason_code) = <key>-%param-ReasonCode.
      DATA(reason_text) = <key>-%param-ReasonText.
      DATA(notify) = <key>-%param-NotifyCustomer.

      " Save status and reason
      MODIFY ENTITIES OF zi_travel IN LOCAL MODE
        ENTITY Travel
          UPDATE FIELDS ( Status RejectionReason )
          WITH VALUE #( (
            %tky            = <key>-%tky
            Status          = 'X'  " Rejected
            RejectionReason = reason_text
          ) ).

      " Optional: Notify customer
      IF notify = abap_true.
        " Send email...
        send_rejection_notification(
          travel_key = <key>-%tky
          reason     = reason_text
        ).
      ENDIF.
    ENDLOOP.

    " Return updated data
    READ ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        ALL FIELDS
        WITH CORRESPONDING #( keys )
      RESULT DATA(travels).

    result = VALUE #( FOR travel IN travels (
      %tky   = travel-%tky
      %param = travel
    ) ).
  ENDMETHOD.

  METHOD reschedule.
    LOOP AT keys ASSIGNING FIELD-SYMBOL(<key>).
      " New dates from parameter
      DATA(new_begin) = <key>-%param-NewBeginDate.
      DATA(new_end) = <key>-%param-NewEndDate.
      DATA(update_price) = <key>-%param-UpdatePrice.

      " Update dates
      MODIFY ENTITIES OF zi_travel IN LOCAL MODE
        ENTITY Travel
          UPDATE FIELDS ( BeginDate EndDate )
          WITH VALUE #( (
            %tky      = <key>-%tky
            BeginDate = new_begin
            EndDate   = new_end
          ) ).

      " Optional: Recalculate price
      IF update_price = abap_true.
        recalculate_price( <key>-%tky ).
      ENDIF.
    ENDLOOP.

    " Return result
    READ ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        ALL FIELDS
        WITH CORRESPONDING #( keys )
      RESULT DATA(travels).

    result = VALUE #( FOR travel IN travels (
      %tky   = travel-%tky
      %param = travel
    ) ).
  ENDMETHOD.
ENDCLASS.

Actions in the Projection

Actions must be exposed in the projection:

projection implementation in class zbp_c_travel unique;
strict ( 2 );

define behavior for ZC_Travel alias Travel
{
  use action cancel;
  use action accept;
  use action rejectWithReason;
  use action reschedule;
  use function calculatePrice;
  use function getAvailability;
}

UI Integration with Fiori Elements

Button Placement

define root view entity ZC_Travel
  provider contract transactional_query
  as projection on ZI_Travel
{
  @UI.lineItem: [
    { position: 10 },
    { type: #FOR_ACTION, dataAction: 'cancel', label: 'Cancel' },
    { type: #FOR_ACTION, dataAction: 'accept', label: 'Release' }
  ]
  @UI.identification: [
    { position: 10 },
    { type: #FOR_ACTION, dataAction: 'rejectWithReason', label: 'Reject' }
  ]
  key TravelUUID,

  // Header Actions
  @UI.fieldGroup: [{ qualifier: 'Actions',
    type: #FOR_ACTION, dataAction: 'reschedule', label: 'Reschedule' }]
  Status
}

Action with Dialog

For actions with input parameters, a dialog is automatically generated:

define abstract entity ZA_RejectionReason
{
  @UI.defaultValue: 'OT'
  @Consumption.valueHelpDefinition: [{ entity: { name: 'ZI_ReasonCode', element: 'Code' }}]
  ReasonCode : abap.char( 2 );

  @UI.multiLineText: true
  ReasonText : abap.string( 255 );

  @UI.defaultValue: 'true'
  NotifyCustomer : abap_boolean;
}

Factory Actions

Factory actions create new instances based on existing ones:

define behavior for ZI_Travel alias Travel
{
  // Factory Action creates new instance
  factory action copyTravel [1];

  // Factory Action with parameter
  factory action createFromBooking parameter ZA_BookingRef [1];
}

Implementation

METHOD copyTravel.
  " Read original data
  READ ENTITIES OF zi_travel IN LOCAL MODE
    ENTITY Travel
      ALL FIELDS
      WITH CORRESPONDING #( keys )
    RESULT DATA(travels).

  LOOP AT travels ASSIGNING FIELD-SYMBOL(<travel>).
    " Create copy with new %cid
    MODIFY ENTITIES OF zi_travel IN LOCAL MODE
      ENTITY Travel
        CREATE FIELDS ( CustomerID BeginDate EndDate Description TotalPrice Currency )
        WITH VALUE #( (
          %cid        = |COPY_{ sy-index }|
          CustomerID  = <travel>-CustomerID
          BeginDate   = <travel>-BeginDate
          EndDate     = <travel>-EndDate
          Description = |Copy of { <travel>-TravelID }|
          TotalPrice  = <travel>-TotalPrice
          Currency    = <travel>-Currency
        ) )
      MAPPED DATA(mapped).

    " mapped contains %cid and %tky of the new instance
    APPEND VALUE #(
      %cid_ref = keys[ sy-index ]-%cid_ref
      %key     = mapped-travel[ 1 ]-%key
    ) TO mapped-travel.
  ENDLOOP.
ENDMETHOD.

Best Practices

Choose Action vs. Function correctly: Actions for modifications, Functions for calculations.
Define Result Type: Always specify result [n] $self so the UI gets updated.
Use IN LOCAL MODE: Bypass authorization checks for internal calls.
Error Handling: Return errors via FAILED and REPORTED:

METHOD cancel.
  " Validation
  IF travel-Status <> 'O'.
    APPEND VALUE #(
      %tky = travel-%tky
      %msg = new_message_with_text(
        severity = if_abap_behv_message=>severity-error
        text     = 'Only open travels can be cancelled'
      )
    ) TO reported-travel.

    APPEND VALUE #( %tky = travel-%tky ) TO failed-travel.
    RETURN.
  ENDIF.
ENDMETHOD.

Combine with Feature Control: Disable actions when they are not applicable.
Transactional Consistency: All changes are committed only at SAVE.

RAP Basics - Fundamentals of the RESTful ABAP Programming Model
Feature Control & Side Effects - Dynamic UI control
Draft Handling in RAP - Intermediate storage with Drafts

RAP Actions and Functions: Implementing Business Logic

Action vs. Function: The Difference

When to Use Action vs. Function?

Bound vs. Unbound (Static)

Instance-bound Action

Behavior Definition

Implementation

Result Cardinality

Static (Unbound) Action

Behavior Definition

Implementation

Function: Calculations Without Side Effects

Behavior Definition

Abstract Entity for Return Values

Implementation

Action with Input Parameters

Behavior Definition

Abstract Entity for Input Parameters

Implementation

Actions in the Projection

UI Integration with Fiori Elements

Button Placement

Action with Dialog

Factory Actions

Implementation

Best Practices

Related Topics