Swagger
Swagger is a set of tools for creating, generating, documenting, and testing RESTful services.
It is centered around a specification file(https://swagger.io/specification/), which contains the description of the REST services, much like a SOAP WSDL or OData metadata file.
There are many powerful tools in the Swagger family, which all are open source:
* Editor
* UI
* Inspector
These tools are free and works in the browser. SAP also use Swagger as part of API management.
ABAP
A while ago I started building a tool for integrating ABAP and Swagger using an inside-out approach.
Lets jump right into it and see how it works, suppose I want to expose the methods of the following class as REST services: CLASS zcl_todo DEFINITION PUBLIC CREATE PUBLIC. PUBLIC SECTION. METHODS create IMPORTING is_data TYPE ztodo_data RETURNING VALUE(rs_key) TYPE ztodo_key . METHODS delete IMPORTING is_key TYPE ztodo_key . METHODS list RETURNING VALUE(rt_list) TYPE ztodo_tt . METHODS update IMPORTING iv_guid TYPE ztodo_key-guid is_data TYPE ztodo_data . ENDCLASS. CLASS ZCL_TODO IMPLEMENTATION. METHOD create. DATA: ls_todo TYPE ztodo. TRY. rs_key-guid = cl_system_uuid=>if_system_uuid_static~create_uuid_c22( ). CATCH cx_uuid_error. ASSERT 0 = 1. ENDTRY. MOVE-CORRESPONDING rs_key TO ls_todo. MOVE-CORRESPONDING is_data TO ls_todo. INSERT ztodo FROM ls_todo. ASSERT sy-subrc = 0. ENDMETHOD. METHOD delete. DELETE FROM ztodo WHERE guid = is_key-guid. ASSERT sy-subrc = 0. ENDMETHOD. METHOD list. SELECT * FROM ztodo INTO TABLE rt_list. “#EC CI_NOWHERE ENDMETHOD. METHOD update. DATA: ls_todo TYPE ztodo. ls_todo-guid = iv_guid. MOVE-CORRESPONDING is_data TO ls_todo. UPDATE ztodo FROM ls_todo. ASSERT sy-subrc = 0. ENDMETHOD. ENDCLASS.
Interface ZIF_SWAG_HANDLER must be implemented, and metadata added for the methods to be exposed, METHOD zif_swag_handler~meta. FIELD-SYMBOLS: LIKE LINE OF rt_meta. APPEND INITIAL LINE TO rt_meta ASSIGNING . -summary = ‘List’(001). -url-regex = ’/list$’. -method = zcl_swag=>c_method-get. -handler = ‘LIST’. APPEND INITIAL LINE TO rt_meta ASSIGNING . -summary = ‘Create’(002). -url-regex = ’/create$’. -method = zcl_swag=>c_method-post. -handler = ‘CREATE’. APPEND INITIAL LINE TO rt_meta ASSIGNING . -summary = ‘Delete’(003). -url-regex = ’/delete$’. -method = zcl_swag=>c_method-post. -handler = ‘DELETE’. APPEND INITIAL LINE TO rt_meta ASSIGNING . -summary = ‘Update’(004). -url-regex = ’/update/(w+)$’. APPEND ‘IV_GUID’ TO -url-group_names. -method = zcl_swag=>c_method-post. -handler = ‘UPDATE’. ENDMETHOD.
Add the handler to a custom SICF node, and thats about it! ABAP-Swagger will automatically generate a spec from the method definitions, and it is possible to use the Swagger UI to test the services. ABAP-Swagger is open source and works from 702 and up.
The full example can be found at https://github.com/larshp/todo_logic
Find more Open Source ABAP projects on dotabap.org
ABAP is like the sun, it will keep shining for a million years http://bit.ly/2F3JR9n #SAP #SAPCloud #AI
