Building an ABAP RESTful Application

1. Create a database table named ZXX_GROCERY.

   1. Right-click on your package ZS4D100_XX in the Project Explorer and choose New → Other ABAP Repository Object. Type table in the filter and choose Database Table. Press Next.

   2. Enter ZXX_GROCERY as the name and Groceries as the description. Press Next to continue.

   3. Choose your existing transport request and press Finish.

2. Adjust the ZXX_GROCERY file by copying the template code and replacing all occurrences of XX with your number.

   1. Replace the generated code in ZXX_GROCERY with the following code:

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      @EndUserText.label : 'Groceries'
      @AbapCatalog.enhancement.category : #NOT_EXTENSIBLE
      @AbapCatalog.tableCategory : #TRANSPARENT
      @AbapCatalog.deliveryClass : #A
      @AbapCatalog.dataMaintenance : #RESTRICTED
      define table zXX_grocery {
      
        key client : abap.clnt not null;
        key id : sysuuid_x16 not null;
        product : abap.char(40);
        category : abap.char(40);
        brand : abap.char(40);
        @Semantics.amount.currencyCode : 'zXX_grocery.currency'
        price : abap.curr(10,2);
        currency : abap.cuky;
        quantity : abap.int2;
        purchasedate : abap.dats;
        expirationdate : abap.dats;
        expired : abap_boolean;
        rating : abap.fltp;
        note : abap.char(255);
        createdby : abp_creation_user;
        createdat : tzntstmpl;
        lastchangedby : abp_lastchange_user;
        lastchangedat : abp_lastchange_tstmpl;
        locallastchanged : abp_locinst_lastchange_tstmpl;
      
      }

   2. Copy the code in the exercise by pressing Copy To Clipboard.

   3. In Eclipse select Edit → Select All.

   4. Select Edit → Delete.

   5. Select Edit → Paste.

   6. Select Edit → Find/Replace.

   7. Enter XX in the Find field and your number in the Replace with field.

   8. Press Replace All.

   9. Press Close.

   10. Press Activate (Ctrl-F3).

   Practice

   ExerciseStart Exercise

1. Generate the additional objects for the RESTful Application Program Sustainable Grocery App.

   1. In the Project Explorer right-click on your database table ZXX_GROCERY and choose Generate ABAP Repository Objects....

   2. Choose ABAP RESTful Application Programming Model → OData UI Service. Press Next.

   3. Enter your package name (ZS4D100_XX) and Press Next.

   4. Select Business Object → Data Model. Check Data Definition Name is ZR_XX_GROCERY and enter the CDS Alias Name: Grocery.

   5. Select Business Object → Behavior and check the default generated names for the Implementation Class is ZBP_R_XX_GROCERY and Draft Table Name is ZXX_GROCERY_D.

   6. Select Service Projection and check the default name is ZC_XX_GROCERY.

   7. Select Business Service → Service Definition. Check the default name is ZUI_XX_GROCERY_O4.

   8. Select Business Service → Service Binding. Check the default name is ZUI_XX_GROCERY_O4 and the binding type is OData V4 - UI.

   9. Press Next.

   10. View the Preview Generator Output and press Finish to generate the objects.

   Practice

   ExerciseStart Exercise

Objects to adjust:

1. Enable the search capabilities in the Data Definition file ZC_XX_GROCERY for fields Product, Category, Brand, ExpirationDate, Expired , and Rating. Replace the code in the data definition file by copying and pasting the solution code below.

   1. Double-click on the data definition file ZC_XX_GROCERY in the Project Explorer to open the file.

   2. Replace the code in the data definition file by copying the following code:

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      @AccessControl.authorizationCheck: #CHECK
       @Metadata.allowExtensions: true
       @Search: { searchable: true }
       @EndUserText.label: 'Projection View for ZR_XX_GROCERY'
       define root view entity ZC_XX_GROCERY
        provider contract transactional_query
        as projection on ZR_XX_GROCERY
      {
          key ID,
          @Search.defaultSearchElement: true
          Product,
          @Search.defaultSearchElement: true
          Category,
          @Search.defaultSearchElement: true
          Brand,
          Price,
          Currency,
          Quantity,
          PurchaseDate,
          @Search.defaultSearchElement: true    
          ExpirationDate,
          @Search.defaultSearchElement: true
          Expired,
          @Search.defaultSearchElement: true
          Rating,
          Note,
          CreatedBy,
          CreatedAt,
          LastChangedBy,
          LocalLastChanged
      }

   3. In the data definition file ZC_XX_GROCERY, press Ctrl-A to select all the contents and then press the Delete key. Press Ctrl-V → to paste the contents previously copied.

   4. Press Ctrl-F. Enter XX in the Find field and your number in the Replace with field. Press Replace All. Press Close.

   5. Press Activate (Ctrl+F3).

   Practice

   ExerciseStart Exercise

Objects to adjust:

1. In the behavior definition file ZR_XX_GROCERY create the action checkExpirationDate and make fields CreatedBy, and CreatedAt read-only.

   1. Double-click on the behavior definition file ZR_XX_GROCERY in the Project Explorer to open the file.

   2. Replace the code in the behavior definition file by copying the following code:

      Code Snippet

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      managed implementation in class ZBP_R_XX_GROCERY unique;
      strict ( 2 );
      with draft;
      
      define behavior for ZR_XX_GROCERY alias Grocery
      persistent table zXX_grocery
      draft table ZXX_GROCERY_D
      etag master LocalLastChanged
      lock master total etag LastChangeDat
      authorization master( global )
      
      {
        field ( readonly )
        ID,
       
      
        field ( numbering : managed )
        ID;
      
        create;
        update;
        delete;
      
        draft action Edit;
        draft action Activate optimized;
        draft action Discard;
        draft action Resume;
        draft determine action Prepare;
      
        
      
        mapping for ZXX_GROCERY
        {
          ID = id;
          Product = product;
          Category = category;
          Brand = brand;
          Price = price;
          Currency = currency;
          Quantity = quantity;
          PurchaseDate = purchasedate;
          ExpirationDate = expirationdate;
          Expired = expired;
          Rating = rating;
          Note = note;
          CreatedBy = createdby;
          CreatedAt = createdat;
          LastChangedBy = lastchangedby;
          LastChangeDat = lastchangedat;
          LocalLastChanged = locallastchanged;
        }
      }

   3. In the behavior definition file ZR_XX_GROCERY, press Ctrl-A to select all the contents and then press the Delete key. Press Ctrl-V to paste the contents previously copied.

   4. Press Ctrl-F. Enter XX in the Find field and your number in the Replace with field. Press Replace All. Press Close.

   5. Press Activate (Ctrl+F3).

2. Generate the action method checkExpirationDate.

   1. In the behavior definition file ZR_XX_GROCERY, find the line that defines the action checkExpiratonDate. It will have a warning that the implementation is missing. Click on the warning in the margin to see a pop-up that states: Add method for action checkExpirationDate.... Double-click this line to generate the method in the implementation class ZBP_R_XX_GROCERY.

   2. The implementation class ZBP_R_XX_GROCERY will open in the editor. Press Activate (Ctrl-F3).

3. To enable the action, add a use action checkExpirationDate; statement to behavior definition file ZC_XX_GROCERY.

   1. Double-click on the behavior definition file ZC_XX_GROCERY in the Project Explorer to open the file.

   2. Replace the code in the behavior definition file by copying the following code:

      Code Snippet

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      projection;
      strict ( 2 );
      use draft;
      
      define behavior for ZC_XX_GROCERY alias Grocery
      use etag
      
      {
          use create;
          use update;
          use delete;
      
          use action Edit;
          use action Activate;
          use action Discard;
          use action Resume;
          use action Prepare;
      
          
      }
      

   3. In the behavior definition file ZR_XX_GROCERY, press Ctrl-A to select all the contents and then press the Delete key. Press Ctrl-V to paste the contents previously copied.

   4. Press Ctrl-F. Enter XX in the Find field and your number in the Replace with field. Press Replace All. Press Close.

   5. Press Activate (Ctrl+F3).

   Practice

   ExerciseStart Exercise

Objects to adjust:

1. Implement the local method checkExpirationDate in the implementation class ZBP_R_XX_GROCERY.

   1. Double-click on the class file ZBP_R_XX_GROCERY in the Project Explorer to open the file.

   2. Click on the Local Types tab bottom of the editor window.

   3. Replace the code in the behavior definition file by copying the following code:

      Code Snippet

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      CLASS lhc_grocery DEFINITION INHERITING FROM cl_abap_behavior_handler.
          PRIVATE SECTION.
            METHODS:
              get_global_authorizations FOR GLOBAL AUTHORIZATION
                  IMPORTING
                  REQUEST requested_authorizations FOR Grocery
                  RESULT result,
              checkExpirationDate FOR MODIFY
                  IMPORTING keys FOR ACTION Grocery~checkExpirationDate RESULT result.
      ENDCLASS.
      
      CLASS lhc_grocery IMPLEMENTATION.
      
      METHOD get_global_authorizations.
      ENDMETHOD.
      
      METHOD checkExpirationDate.
      
          DATA: lt_groceries TYPE TABLE FOR READ RESULT zr_xx_grocery,
                ls_grocery TYPE STRUCTURE FOR READ RESULT zr_xx_grocery,
                lv_expiration TYPE d,
                lv_current_date TYPE d,
                lv_expired TYPE abap_boolean,
                lt_update_groceries TYPE TABLE FOR UPDATE zr_xx_grocery.
      
          READ ENTITIES OF zr_xx_grocery
            IN LOCAL MODE ENTITY Grocery
            ALL FIELDS WITH CORRESPONDING #( keys )
            RESULT lt_groceries.
      
          LOOP AT lt_groceries INTO ls_grocery.
            lv_expiration = ls_grocery-Expirationdate.
            lv_current_date = cl_abap_context_info=>get_system_date( ).
            IF lv_expiration < lv_current_date.
              lv_expired = abap_true.
            ELSE.
              lv_expired = abap_false.
            ENDIF.
      
          APPEND VALUE #( id = ls_grocery-Id expired = lv_expired )
            TO lt_update_groceries.
          MODIFY ENTITIES OF zr_xx_grocery IN LOCAL MODE
            ENTITY Grocery
            UPDATE FIELDS ( expired )
            WITH lt_update_groceries.
          ENDLOOP.
      
          result = VALUE #( FOR groceries IN lt_groceries
            ( id = groceries-id %param = groceries ) ).
      ENDMETHOD.
      ENDCLASS.
      

   4. In the class file ZBP_XX_GROCERY, press Ctrl-A to select all the contents and then press the Delete key. Press Ctrl-V to paste the contents previously copied.

   5. Press Ctrl-F. Enter XX in the Find field and your number in the Replace with field. Press Replace All. Press Close.

   6. Press Activate (Ctrl+F3).

   Practice

   ExerciseStart Exercise

Objects to adjust:

1. Customize the user interface (UI) by adding @UI annotations to the metadata extension file ZC_XX_GROCERY. @UI.lineITem refers to the initial list, while @UI.identification refers to the detail list on a second screen. The annotations are placed before the field name. Here are some sample @UI commands:

   @UI.hidden: true

   Hides the field from display

   @UI.lineItem.position

   Order the fields from left to right with lower numbers to the right and higher numbers to the left

   @UI.lineItem.importance

   Which devices should display item:

   #HIGH - all screen sizes (desktops, tablets, and smartphones)

   #MEDIUM - large (desktops) and medium (tablet) screens

   #LOW - large screens (Desktops)

   @UI.lineItem.label

   Label of field

   1. Double-click on the metadata extension file ZC_XX_GROCERY in the Project Explorer to open the file.

   2. Replace the code in the behavior definition file by copying the following code:

      Code Snippet

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      @Metadata.layer: #CORE
      @UI: {
          headerInfo: {
          typeName: 'Sustainable Grocery App',
          typeNamePlural: 'Sustainable Groceries App'
        }
      }
      annotate view ZC_XX_GROCERY with
      {
        @UI.facet: [ {
          id: 'idIdentification',
          type: #IDENTIFICATION_REFERENCE,
          label: 'Sustainable Groceries App',
          position: 10
        } ]
        @UI: { lineItem: [ { exclude: true } ,
        { type: #FOR_ACTION,
          dataAction: 'checkExpirationDate' ,
          label: 'Check for expiration' } ] ,
      identification: [ { position: 1, label: 'ID' } ,
        { type: #FOR_ACTION,
          dataAction: 'checkExpirationDate',
          label: 'Check for expiration' } ] }
      
          @UI.hidden: true
          ID;
      
          @UI.lineItem: [ {
            position: 10 ,
            importance: #HIGH,
            label: 'Product'
          } ]
          @UI.identification: [ {
            position: 10 ,
            label: 'Product'
          } ]
          Product;
      
          @UI.lineItem: [ {
            position: 20 ,
            importance: #MEDIUM,
            label: 'Category'
          } ]
          @UI.identification: [ {
            position: 20 ,
            label: 'Category'
          } ]
          Category;
      
          @UI.lineItem: [ {
            position: 30 ,
            importance: #MEDIUM,
            label: 'Brand'
          } ]
          @UI.identification: [ {
            position: 30 ,
            label: 'Brand'
          } ]
          Brand;
      
          @UI.lineItem: [ {
            position: 40 ,
            importance: #MEDIUM,
            label: 'Price/Currency'
          } ]
          @UI.identification: [ {
            position: 40 ,
            label: 'Price/Currency'
          } ]
          Price;
      
          @UI.hidden: true
          Currency;
      
          @UI.lineItem: [ {
            position: 60 ,
            importance: #MEDIUM,
            label: 'Quantity'
          } ]
          @UI.identification: [ {
            position: 60 ,
            label: 'Quantity'
          } ]
          Quantity;
      
          @UI.lineItem: [ {
            position: 70 ,
            importance: #MEDIUM,
            label: 'Purchase Date'
          } ]
          @UI.identification: [ {
            position: 70 ,
            label: 'Purchase Date'
          } ]
          PurchaseDate;
      
          @UI.lineItem: [ {
            position: 80 ,
            importance: #MEDIUM,
            label: 'Expiration Date'
          } ]
          @UI.identification: [ {
            position: 80 ,
            label: 'Expiration Date'
          } ]
          ExpirationDate;
      
          @UI.lineItem: [ {
            position: 90 ,
            importance: #MEDIUM,
            label: 'Expired'
          } ]
          @UI.identification: [ {
          position: 90,
          label: 'Expired'
          } ]
          Expired;
      
          @UI.lineItem: [ {
            position: 100 ,
            importance: #MEDIUM,
            label: 'Rating'
          } ]
          @UI.identification: [ {
            position: 100 ,
            label: 'Rating'
          } ]
          Rating;
      
          @UI.lineItem: [ {
            position: 110 ,
            importance: #MEDIUM,
            label: 'Note'
          } ]
          @UI.identification: [ {
            position: 110 ,
            label: 'Note'
          } ]
          Note;
      
          @UI.hidden: true
          CreatedBy;
        
          @UI.hidden: true
          CreatedAt;
      
          @UI.hidden: true
          LastChangedBy;
      
          @UI.hidden: true
          LocalLastChanged;
      }
      

   3. In the metadata extension file ZC_XX_GROCERY, press Ctrl-A to select all the contents and then press the Delete key. Press Ctrl-V to paste the contents previously copied.

   4. Press Ctrl-F. Enter XX in the Find field and your number in the Replace with field. Press Replace All. Press Close.

   5. Press Activate (Ctrl+F3).

   Practice

   ExerciseStart Exercise

Objects to adjust:

1. Publish and test the service.

   1. Double-click on the service bindings file ZUI_XX_GROCERY_04 in the Project Explorer to open the file.

   2. Expand the service ZUI_XX_GROCERY_04 in the services table and select the line below with Version entry 1.0.0. Press the Publish button. The publishing will take a few minutes.

   Practice

   ExerciseStart Exercise

Objects to adjust:

1. Preview the Sustainable Grocery App service.

   1. Double-click on the service bindings file ZUI_XX_GROCERY_04 in the Project Explorer to open the file.

   2. In the Service Version Details section, select Grocery in the Entity Set and Association list.

   3. Press Preview... to launch the application.

2. Create a new product entry

   1. Choose Create in the application.

   2. Enter product Details:

      Product	Oatmeal
      Category	Breakfast
      Brand	Organics
      Price	5.00
      Currency	USD
      Quantity	1
      Purchase Date	Choose 3 weeks ago from today
      Expiration Date	Choose 3 days from today
      Expired	Unchecked
      Rating	5
      Note	Yummy

   3. Press Create.

   4. Press the Alt+Left arrow to go back to the previous screen.

   5. Press GO to view your new product.

3. Check expiration processing.

   1. Select the check box to the right of your product.

   2. Press Check for Expiration. Note field Expired with a value of No.

   3. Click on the product line to go to the detail page.

   4. Choose Edit to change the product.

   5. Change the Expiration Date to 1 day ago.

   6. Press Save.

   7. Press Check for expiration. Notice fields Expired now with a value of Yes.

   8. Press the Alt+Left arrow to go back to the first page.

   Practice

   ExerciseStart Exercise