--- parser: v2 auto_validation: true time: 30 tags: [ tutorial>intermediate, software-product>sap-btp--abap-environment, software-product>sap-business-technology-platform, topic>abap-connectivity, tutorial>license] primary_tag: programming-tool>abap-development author_name: Julie Plummer author_profile: https://github.com/julieplummer20 slug: abap-environment-a4c-create-custom-entity canonical_url: https://developers.sap.com/tutorials/abap-environment-a4c-create-custom-entity --- # Implement a Custom Entity and API Execution (Query Implementation) Class In the SAP Business Technology Platform, ABAP Environment, implement a CDS custom entity and query implementation class; then display the output in a Fiori Elements preview ## Prerequisites - **IMPORTANT**: This tutorial cannot be completed on a trial account - **IMPORTANT**: This tutorial is part of a mission. You must complete the previous parts first; otherwise, you may experience errors or unexpected behavior. The link to the mission is available at the top right of the screen, immediately above the list of steps ## You will learn - How to implement a query manually for your CDS custom entity - How to display the data retrieved in a Fiori Elements preview This tutorial is based on: - [Using a CDS Custom Entity for Data Modeling](https://help.sap.com/viewer/923180ddb98240829d935862025004d6/Cloud/en-US/6436a50d7d284f01af2cca7a76c7116a.html) - [Implementing the Query for Service Consumption](https://help.sap.com/viewer/923180ddb98240829d935862025004d6/Cloud/en-US/c33503ae1e794e3aad0d2e122f465611.html) - [Implementing Data and Count Retrieval](https://help.sap.com/viewer/923180ddb98240829d935862025004d6/Cloud/en-US/33497472ad294918b8a0184d9d8369bd.html) Therefore, this tutorial will only cover in detail those aspects that are different. In this case, you are not including both remote and local data, you are only retrieving local data. Therefore, you do not include the local calculated fields, `DiscountPct` and `DiscountAbs`. --- ### Add query provider interface to class You have already tested the connection by displaying data in an ABAP Console app. You will now display this data in a Fiori Elements preview, using a custom entity. 1. First, open the class **`ZCL_PROXY_TRAVELS_###`** and add the interface **`IF_RAP_QUERY_PROVIDER`** to the class definition. ```ABAP INTERFACES: if_oo_adt_classrun, if_rap_query_provider. ``` > The signature of the method `IF_RAP_QUERY_PROVIDER~SELECT` contains the import parameter `io_request`. This parameter represents the OData query options that are delegated from the UI and used as input for the SELECT method. Whenever the OData client requests data, the query implementation class must return the data that matches the request, or throw an exception if the request cannot be fulfilled. 2. You will get a warning: "Implementation missing for method `IF_RAP_QUERY_PROVIDER~SELECT`." Select the warning and choose **Quick Fix (`Ctrl+1`)** from the context menu. Then choose the fix **Add implementation for select**. An empty method implementation is added. 3. Format, save, and activate ( **Sh+F1, Ctrl+S, Ctrl+F3** ) your class. ### Specify class in your custom entity 1. Open your CDS custom entity by choosing **Core Data Services > Data Definitions** > **`ZCE_TRAVEL_DATA_###`**, which you created in [Create a Service Consumption Model](abap-environment-create-service-consumption-model). 2. Add the following annotation to the view (immediately after the '@EndUserText.label' annotation), pointing to the class you have just created - **IMPORTANT: Use upper case!** ```CDS @ObjectModel.query.implementedBy: 'ABAP:ZCL_PROXY_TRAVELS_###' ``` ### Implement SELECT method in query implementation class You will retrieve the travel data using the same method **`get_travels`** as before. This time, however, you will output the data to a Fiori Elements preview, by implementing the method **`if_rap_query_provider~select`** 1. Add the following statements to **`METHODS get_travels`** in the **CLASS ... DEFINITION**. ```ABAP IMPORTING top TYPE i OPTIONAL skip TYPE i OPTIONAL ``` 2. Now add the following code to the method **`if_rap_query_provider~select.`** in the **CLASS...IMPLEMENTATION**. ```ABAP METHOD if_rap_query_provider~select. DATA business_data TYPE TABLE OF zce_travel_data_###. DATA(top) = io_request->get_paging( )->get_page_size( ). DATA(skip) = io_request->get_paging( )->get_offset( ). DATA(requested_fields) = io_request->get_requested_elements( ). DATA(sort_order) = io_request->get_sort_elements( ). TRY. get_travels( EXPORTING top = CONV i( top ) skip = CONV i( skip ) IMPORTING et_business_data = business_data ) . io_response->set_total_number_of_records( lines( business_data ) ). io_response->set_data( business_data ). CATCH cx_root INTO DATA(exception). DATA(exception_message) = cl_message_helper=>get_latest_t100_exception( exception )->if_message~get_longtext( ). ENDTRY. ENDMETHOD. ``` 3. Format, save and activate ( **`Sh+F1, Ctrl+S, Ctrl+F3`** ) the class. ### Check the code for your query implementation class ```ABAP PUBLIC FINAL CREATE PUBLIC . PUBLIC SECTION. TYPES t_business_data TYPE TABLE OF z###_model_travels=>tys_simple_travel_type. METHODS get_travels IMPORTING top TYPE i OPTIONAL skip TYPE i OPTIONAL EXPORTING et_business_data TYPE t_business_data * * RAISING * /iwbep/cx_cp_remote * /iwbep/cx_gateway * cx_web_http_client_error * cx_http_dest_provider_error . INTERFACES if_oo_adt_classrun . INTERFACES if_rap_query_provider . PROTECTED SECTION. PRIVATE SECTION. ENDCLASS. CLASS zcl_get_travels_### IMPLEMENTATION. METHOD get_travels. " Variables for http_client and client_proxy DATA: lo_http_client TYPE REF TO if_web_http_client, lo_client_proxy TYPE REF TO /iwbep/if_cp_client_proxy, lo_request TYPE REF TO /iwbep/if_cp_request_read_list, lo_response TYPE REF TO /iwbep/if_cp_response_read_lst. " 1. Get the destination of remote system; Create http client DATA(lo_destination) = cl_http_destination_provider=>create_by_comm_arrangement( comm_scenario = 'Z_OUTBOUND_ODATA_CSCEN_###' ** comm_system_id = '' * service_id = '' ). lo_http_client = cl_web_http_client_manager=>create_by_http_destination( lo_destination ). "2. create client proxy lo_client_proxy = /iwbep/cl_cp_factory_remote=>create_v2_remote_proxy( EXPORTING is_proxy_model_key = VALUE #( repository_id = 'DEFAULT' proxy_model_id = 'Z###_MODEL_TRAVELS' proxy_model_version = '###1' ) io_http_client = lo_http_client iv_relative_service_root = '/sap/opu/odata/sap/Z_C_TRAVEL_API_O2_###' " = the service endpoint in the service binding in PRV' ). ). ASSERT lo_http_client IS BOUND . " 3. Navigate to the resource and create a request for the read operation lo_request = lo_client_proxy->create_resource_for_entity_set( 'SIMPLE_TRAVEL' )->create_request_for_read( ). lo_request->set_top( 50 )->set_skip( 0 ). " 4. Execute the request and retrieve the business data lo_response = lo_request->execute( ). lo_response->get_business_data( IMPORTING et_business_data = et_business_data ). " Handle remote Exception ENDMETHOD. METHOD if_oo_adt_classrun~main. DATA business_data TYPE TABLE OF z###_model_travels=>tys_simple_travel_type. TRY. get_travels( IMPORTING et_business_data = business_data ) . out->write( business_data ). CATCH cx_root INTO DATA(exception). out->write( cl_message_helper=>get_latest_t100_exception( exception )->if_message~get_text( ) ). ENDTRY. ENDMETHOD. METHOD if_rap_query_provider~select. DATA business_data TYPE TABLE OF z###_model_travels=>tys_simple_travel_type. DATA(top) = io_request->get_paging( )->get_page_size( ). DATA(skip) = io_request->get_paging( )->get_offset( ). DATA(requested_fields) = io_request->get_requested_elements( ). DATA(sort_order) = io_request->get_sort_elements( ). TRY. get_travels( EXPORTING top = CONV i( top ) skip = CONV i( skip ) IMPORTING et_business_data = business_data ) . io_response->set_total_number_of_records( lines( business_data ) ). io_response->set_data( business_data ). CATCH cx_root INTO DATA(exception). DATA(exception_message) = cl_message_helper=>get_latest_t100_exception( exception )->if_message~get_longtext( ). ENDTRY. ENDMETHOD. ENDCLASS. ``` ### Create service definition 1. Select your custom entity **`ZCE_TRAVEL_DATA_###`** and choose **New > Create Service Definition** from the context menu. 2. In the wizard, enter the following: - Name: **`ZCE_TRAVEL_DATA_###`** - Description **Service - Travel data from remote system** - Source Type: Definition - (The referenced object: **`ZCE_TRAVEL_DATA_###`** should be entered automatically) - Choose **Next** ![step4a-sd-wizard](https://raw.githubusercontent.com/sap-tutorials/abap-core-development/main/tutorials/abap-environment-a4c-create-custom-entity/step4a-sd-wizard.png) 3. Accept the transport request and choose **Finish**. The service definition opens in a new editor. 4. Optional: Add a semantic alias for the service, here **`SimpleTravels`**: ```CDS expose ZCE_TRAVEL_DATA_### as SimpleTravels; ``` 5. Choose **Save** and **Activate**. > Generally, the custom entity and service definition are part of the same business object and have the same name. ### Create service binding 1. Select your service definition, **`ZCE_TRAVEL_DATA_###`** and choose **New > Create Service Binding** from the context menu. ![step2a-create-service-binding](https://raw.githubusercontent.com/sap-tutorials/abap-core-development/main/tutorials/abap-environment-a4c-create-custom-entity/step2a-create-service-binding.png) 2. In the wizard: - Enter a name: **`ZCE_TRAVEL_DATA_###_UI_O2`** and description **`Endpoint for ZCE_TRAVEL_DATA_###`** - Enter the binding type: **`ODATA V2 - UI`** - Choose **Next** ![step5b-create-sb-wizard](https://raw.githubusercontent.com/sap-tutorials/abap-core-development/main/tutorials/abap-environment-a4c-create-custom-entity/step5b-service-binding-wizard.png) 3. Accept the transport request and choose **Finish**. The service binding opens in a new editor. 4. Choose **Activate**. On the left is the Service Definition, `ZCE_TRAVEL_DATA_###`. On the right, is the active service, including the Entity Set and the Service URL. 5. Select the entity Set **Travel** and choose **Preview**. ![step7b-service-binding-editor](https://raw.githubusercontent.com/sap-tutorials/abap-core-development/main/tutorials/abap-environment-a4c-create-custom-entity/step7b-service-binding-editor.png) The Fiori Elements preview for your remote OData service appears in the browser, but without any data. 6. Choose **Settings > Select All > OK**, then choose **Go**. Your Fiori Elements preview should look roughly like this: ![step7c-fiori](https://raw.githubusercontent.com/sap-tutorials/abap-core-development/main/tutorials/abap-environment-a4c-create-custom-entity/step7c-fiori.png) ### Check the code for your custom entity Add a label for the **`BeginDate`** and **`EndDate`**. Your code should now look like this. ```ABAP @EndUserText.label: 'Travel data custom entity from PRV' @ObjectModel.query.implementedBy: 'ABAP:ZCL_PROXY_TRAVELS_###' define custom entity ZCE_TRAVEL_DATA_### { @UI.lineItem: [ { position: 10 } ] key TravelID : abap.numc( 8 ); @UI.lineItem: [ { position: 20 } ] AgencyID : abap.numc( 6 ); @UI.lineItem: [ { position: 30 } ] CustomerID : abap.numc( 6 ); @UI.lineItem: [ { position: 40, label: 'Start Date'} ] BeginDate : rap_cp_odata_v2_edm_datetime; @UI.lineItem: [ { position: 50, label: 'End Date'} ] EndDate : rap_cp_odata_v2_edm_datetime; @Semantics.amount.currencyCode: 'CurrencyCode' BookingFee : abap.dec( 16, 2 ); @Semantics.amount.currencyCode: 'CurrencyCode' TotalPrice : abap.dec( 16, 2 ); @Semantics.currencyCode: true CurrencyCode : abap.cuky( 5 ); Description : abap.char( 1024 ); //renamed element Status : abap.char( 1 ); LastChangedAt : tzntstmpl; CalculatedEtag : abap.string( 0 ); } ``` The SAP Fiori elements preview should now open looking like this. ![step9-fiori-improved](https://raw.githubusercontent.com/sap-tutorials/abap-core-development/main/tutorials/abap-environment-a4c-create-custom-entity/step9-fiori-improved.png) ### Test yourself ---