Extend the RAP Travel Application to integrate workflow capability

Extend the Business Object Behaviour definition with Determination On Save.

1. Go to behaviour definition of the Travel root entity
   
   ZR_RAP_TRAVEL_#### and define the determination trigger_travelworkflow. For that, insert the following code as shown in the screenshot below.

    determination trigger_travelworkflow on save `{create;}`

Short explanation: This statement specifies that the determination would be triggered during the save event of the operation Create. The determined values would be visible after save.

1. Activate

   
   the changes

2. Click on the Quick Assist

   
   besides the newly added line of code and the Add method for determination to declare the required method in behavior implementation class.
   

3. As a result, you can see the method trigger_travelworkflow for determination is added in the local handler class LHC_TRAVEL of Behaviour implementation class ZBP_R_RAP_TRAVEL_RD02

   

   Short Explanation:

   • The addition FOR DETERMINE indicates that the method provides the implementation of a determination and the addition ON SAVE indicates the specified trigger time (during save event).

   • IMPORTING parameter keys – is an internal table containing the keys of the instances the determination will be executed on. Includes all entities for which keys must be assigned.

   • Implicit CHANGING parameter reported - used to return messages in case of failure.

4. Activate

   
   the changes

You will now implement the determination to call trigger workflow method created as part of the previous tutorial and update the overall status of Travel to (W) Awaiting Approval using (EML) Entity Manipulation Language In Local Mode.

Calling EML statements in the local mode - by using the addition IN LOCAL MODE –excludes feature controls and authorization checks. This addition can thus be used to change a BO Instance locally by the same RAP business object itself, i. e. not for other RAP business objects.

1. Define the local constant travel_status to store the allowed value of the overall status of a Travel instance. Insert the following code snippet in the definition part of the local handler class lhc_travel in Private section as shown on the screenshot below.

   Insert the following code snippet.

   ABAP Code:

   Copy

      CONSTANTS
        "Travel Status:
        BEGIN OF travel_status
          open TYPE c Length 1 Value 'O', "Open
          accepted TYPE c Length 1 Value 'A', "Accepted
          rejected TYPE c Length 1 Value 'R', "Rejected
          waiting TYPE c Length 1 Value 'W', "Awaiting Approval
      End of travel_status 
   

   Your code should look like

   

2. Implement the method trigger_travelworkflow in the local class lhc_travel of the Business Object Behaviour Implementation Class ZBP_R_RAP_TRAVEL_####.

   Insert the following code snippet in the method and replace all occurrences of the placeholder #### with your group ID. You can use the F1 help to get detailed information on each EML statement

   ABAP Code:

   Copy

      METHOD trigger_travelworkflow.
   
          IF keys IS NOT INITIAL.
   
          READ ENTITIES OF ZR_RAP_Travel_RD02 IN LOCAL MODE
          ENTITY travel
              ALL FIELDS
              WITH CORRESPONDING #( keys )
              RESULT DATA(travels).
   
           data(ls_travel) = travels[ 1 ].
   
          SELECT SINGLE name FROM /DMO/I_Agency WHERE AgencyID = @ls_travel-AgencyID
          INTO @DATA(agency_name).
   
          SELECT SINGLE firstname, lastname, title FROM /DMO/I_Customer
          WHERE CustomerID = @ls_travel-customerID
          INTO ( @DATA(firstname), @DATA(lastname), @DATA(title) ).
   
         IF sy-subrc = 0.
   
         CONCATENATE title firstname lastname INTO DATA(Customer_name) SEPARATED BY space.
   
   
          NEW zcl_r_rap_workflow_rd02( )->trigger_workflow(
            travelid       = ls_travel-travelid
            agency_name    = agency_name
            booking_fee    = ls_travel-bookingfee
            Currency_code  = ls_travel-currencycode
            Customer_name  = Customer_name
            Total_price    = ls_travel-Totalprice
          ).
   
          " Replace the suffix with your choosen group id.
          "This is done to update the Overall Travel Status to Awaiting Approval.
          MODIFY ENTITIES OF ZR_RAP_TRAVEL_RD02 IN LOCAL MODE
                ENTITY travel
                   UPDATE FIELDS ( OverallStatus )
                   WITH VALUE #( FOR key IN keys ( %tky          = key-%tky
                                              OverallStatus = travel_status-waiting ) )
                  FAILED DATA(ls_failed)
                  REPORTED DATA(ls_reported).
            ENDIF.
           ENDIF.
          ENDMETHOD.
   

   your code should look like

   

   Short Explanation

   • Read the travel instance(s) data with the transferred keys (**keys**) using the EML statement READ ENTITIES IN Local MODE.
   • Enrich the data by getting Agency Name and Customer name, by reading from the CDS Views.
   • Call the method trigger_workflow from workflow handler class zcl_r_rap_workflow_#### to trigger workflow by passing all the required data retrieved in the previous steps.
   • As a final step update the Overall Travel Status to Awaiting Approval by EML statement MODIFY ENTITIES IN Local Mode using the transferred keys (keys).

3. Activate

   
   the changes

   Where to trigger the workflow from, in case of Unmanaged Numbering?
   The actions required to trigger a workflow instance are defined as save actions and can thus only be called during the early or late save phase of a RAP Business Object.
   Choosing between early or late phase totally depends on how you are generating the numbering for the key field like in this case Travel ID. As the key would be required for your identifying the entry during callback processing.

   Early Numbering: Trigger the workflow instance in a determination on save with the required methods.

   Late Numbering: Trigger the workflow in a determination on save. To get the generated key field , you can set the payload with the setPayload method even later in the adjust_numbers method.

Without proper values for Customer ID and Agency ID the read on the CDS views to get Customer Name and Agency Name would not work. Thus, add value help to the fields to select values.

1. Go to metadata extensions for your RAP application

   

2. Using the below annotation add value help for Agency ID.
   Insert this code above the field name AgencyID in Metadata Extension.

   ABAP Code:

   Copy

      @Consumption.valueHelpDefinition: 
       [{entity: { name: ' /DMO/I_Agency_StdVH', 
         element: ' AgencyID'  }}]`
   

3. Using the below annotation add value help for Customer ID.
   Insert this code above the field name CustomerID in Metadata Extension.

   ABAP Code:

   Copy

     @Consumption.valueHelpDefinition: 
      [{entity: { name: '/DMO/I_Customer_StdVH', 
        element: 'CustomerID'  }}]
   

   Short explanation: Here entity name is the Value help CDS View for field and element name in the corresponding field name in Value Help CDS View for which the Value help is being provisioned.

   Value Help should now be available for the fields.

   With this you are done with the implementation part, further we will see how to Preview, run, monitor, and troubleshoot the Travel App.

   In case your value help shows no data try to clear your browser cache or try previewing the application with browser in Inprivate or Incognito mode.