All Blogs in this Series –

AI Powered Invoice Management with SAP RAP and ABAP on Cloud

AI Powered Invoice Management with SAP RAP and ABAP on Cloud – Part 1

AI Powered Invoice Management with SAP RAP and ABAP on Cloud – Part 2

AI Powered Invoice Management with SAP RAP and ABAP on Cloud – Part 3

If you want to know the reference of this blog, please go through the Part 1 & Part 2 sections of this AI Powered Invoice Management Series.

This is going to be the last part of the AI Powered Invoice Management Series. What we are focusing here is –

1. Creating a Unmanaged scenario
2. Creation of a ABAP Workflow
3. Creation of a NodeJS based Wrapper on top of the ABAP Unmanaged API

Process Flow

On-premise developments ( Create RAP Unmanaged API )

Create a custom table –

Create CDS Entity

@AccessControl.authorizationCheck: #NOT_REQUIRED
@EndUserText.label: 'Interface of WF Trigger'
define root view entity Z_I_INV_PO_WF 
 as select from 
// zinv_po_status 
 ekko left outer join 
 zinv_po_status on ekko.ebeln = zinv_po_status.ebeln 
{
// key ekko.ebeln,
 key zinv_po_status.ebeln,
 zinv_po_status.amount,
 zinv_po_status.status 
}

Create a Projection view –

@EndUserText.label: 'Peojection view for INV PO WF'
@AccessControl.authorizationCheck: #NOT_REQUIRED
define root view entity Z_P_INV_PO_WF 
provider contract transactional_query
as projection on Z_I_INV_PO_WF {
 key ebeln,
 amount,
 status 
}

Create Behavior Definition –

unmanaged
implementation in class zbp_i_inv_po_wf unique;
define behavior for Z_I_INV_PO_WF 
{
 create;
} 
projection;
//strict;
define behavior for Z_P_INV_PO_WF //alias <alias_name>
{
 use create;
// use update;
// use delete;
}

Implement the Behavior class

CLASS lhc_z_i_inv_po_wf DEFINITION INHERITING FROM 
cl_abap_behavior_handler.
 PRIVATE SECTION.
 METHODS create FOR MODIFY
 IMPORTING entities FOR CREATE z_i_inv_po_wf.
 METHODS read FOR READ
 IMPORTING keys FOR READ z_i_inv_po_wf RESULT result.
ENDCLASS.
CLASS lhc_z_i_inv_po_wf IMPLEMENTATION.
 METHOD create.
 DATA: ls_line TYPE zinv_po_status,
 lt_lines TYPE TABLE OF zinv_po_status.
 LOOP AT entities ASSIGNING FIELD-SYMBOL(<ls_entity>).
 ls_line = CORRESPONDING #( <ls_entity> ).
 APPEND ls_line TO lt_lines.
 DATA : lv_objectkey TYPE swr_struct-object_key.
 DATA: lt_input_container TYPE TABLE OF swr_cont,
 lv_subrc TYPE sy-subrc,
 lv_value TYPE swe_evtid,
 lt_msglns TYPE TABLE OF swr_messag,
 lt_msgstr TYPE TABLE OF swr_mstruc.
 lv_objectkey = ls_line-ebeln.
 lt_input_container = VALUE #( ( element = 'PurchasingDocument'
value = ls_line-ebeln ) ( element = 'TargetValue' value = ls_lineamount ) ).
 CALL FUNCTION 'SAP_WAPI_CREATE_EVENT' STARTING NEW TASK 
lv_objectkey 
 EXPORTING
 object_type = 'ZINV_PUORD'
 object_key = lv_objectkey 
 event = 'PROCESS_PAY_FOR_INV'
 TABLES
 input_container = lt_input_container 
 message_lines = lt_msglns 
 message_struct = lt_msgstr.
 ENDLOOP.
 zcl_inv_payment=>update_table( it_table = lt_lines ).
 ENDMETHOD.
 METHOD read.
 ENDMETHOD.
ENDCLASS.
CLASS lsc_z_i_inv_po_wf DEFINITION INHERITING FROM 
cl_abap_behavior_saver.
 PROTECTED SECTION.
 METHODS finalize REDEFINITION.
 METHODS check_before_save REDEFINITION.
 METHODS save REDEFINITION.
 METHODS cleanup REDEFINITION.
 METHODS cleanup_finalize REDEFINITION.
ENDCLASS.
CLASS lsc_z_i_inv_po_wf IMPLEMENTATION.
 METHOD finalize.
 ENDMETHOD.
 METHOD check_before_save.
 ENDMETHOD.
 METHOD save.
 ENDMETHOD.
 METHOD cleanup.
 ENDMETHOD.
 METHOD cleanup_finalize.
 ENDMETHOD.
ENDCLASS.

On-premise developments ( Workflow Developments )

Create a basic workflow –

Now implement global variables –

Add decisions Approve and Reject in the Workflow

Configure the bindings

Create Events in SWo1 and set the parameters –

Here are the parameter lists of the workflow –

SAP CF NodeJS Express server to trigger the Workflow

Create a NPM package and create index.js

var express = require('express'); 
var app = express(); 
var PORT = 8080; 
var lib = require('./lib'); 
app.use(express.json()); 
app.use(express.urlencoded({ extended: true })); 
app.post('/trigger_wf', async function (req, res) { 
 await lib.trigger_wf(req, res); 
}); 
app.get('/', async function (req, res) { 
 await lib.base(req, res); 
}); 
app.listen(PORT, function (err) { 
 if (err) console.log(err); 
 console.log("Server listening on PORT", PORT); 
}); 

Now create the lib.js file

const SapCfAxios = require('sap-cf-axios').default; 
const xsenv = require('@sap/xsenv'); 
module.exports = { 
 base: async function base(req, res) { 
 res.send(JSON.stringify({ 'uri': '/trigger_wf' })); 
 }, 
 trigger_wf: async function trigger_wf(req, res) { 
 var custurl = process.env['MURL']; 
 console.log('I am here'); 
 // var data = req.body;
 console.log('--------------------') 
 console.log(req.body); 
 var data = req.body; 
 var post_body = { 
 "ebeln": data.ebeln, 
 "amount": data.amount, 
 "status": data.status
 } 
 console.log(post_body); 
 try { 
 console.log('--------------------') 
 const axios_DUMMY_GET = SapCfAxios('DUMMY_GET'); 
 const response = await axios_DUMMY_GET({ 
 method: 'post', 
 url: custurl, 
 headers:{ 
 "X-Requested-With" : "X"
 }, 
 data: post_body
 }); 
 console.log('--------------------') 
 console.log(JSON.stringify(response.data.d)) 
 res.json({ "STATUS": "Post Successful" }); 
 } catch (error) { 
 console.log(JSON.stringify(error)); 
 res.json({ "STATUS": "Error in Post", "MES":
JSON.stringify(error) }); 
 } 
 } 
}

and use manifest.yml file to deploy your nodejs to cloud foundry environment

Note – Here sap-cf-axios is used to create a secure communication tunnel to call the on-premise destination through the SAP BTP destination and Cloud Connectors.

Thanks for having patience reading out the blog till the end. Hope to hear from you….