AS/400 COBOL RPC SDK Exercise

Introduction

This exercise will develop your skills with OpenLegacy IDE by generating Java models from existing sources and creating unit tests to validate backend connectivity and data.

Pre-Requirements

OpenLegacy IDE version 4.5.5 (Full installation including JDK and all Maven dependencies).
Internet Connection

Exercise Resources

ItemDetails.cbl - COBOL program.

Exercise Definition

Create a new SDK Project.
Generate Java model (entity) from COBOL source file.
Develop unit tests on the fly.
Test the connectivity and data retrieval from the AS/400 host.

Step 1 – Create a New SDK Project

First, we will create a new SDK project using OpenLegacy IDE.
The purpose of the SDK project is to allow easy access to legacy backends, using standard and easy to use Java code.

Project Setup

Create a new OpenLegacy AS/400 RPC project.

Open the New Project Wizard:
- File → New → OpenLegacy SDK Project
Define the Project Name as as400-cobol-rpc-sdk.
Click at the Default Package field, to automatically fill it up.
Select AS/400 RPC as the backend and click Next.
Set the connection details to the backend based on the following parameters:
- Host Name/IP: as400.openlegacy.com
- Code Page: 37
- Username: OPENLEGA1
- Password: OPENLEGA
Click Finish.

Testing the Configuration

Make sure your environment has no errors.
Do a Maven update if needed.
Do a project -> clean if needed (not Maven clean).

Congratulations! You are ready to start working on the API.

Step 2 – Generate Java Model (entity) from COBOL File

Let's create Java models out of our demo COBOL file.

Open ItemDetails.cbl located at src/main/resources/sample folder.
Right-click on the file → OpenLegacy → Generate Model
In the 'Execute Action Path' field, write /QSYS.LIB/RMR2L1.LIB/FULLDETAIL.PGM
Check Generate JUnit Test checkbox
Click OK

Step 3 – Create a JUnit Test

OpenLegacy enables test-driven development by auto-generating test suites for each backend program (entities). We can extend this test suite with additional unit tests to validate our connectivity to the backend. The tests are auto-generated, and all you have to do is to provide a JSON format input and output to test againt the backend.

Open src/test/resources/mock/ItemdetailsTest/test_itemdetailsTest_usecase_1.input.json and change the itemNum field to 1000 for the input.
Open src/test/resources/mock/ItemdetailsTest/test_itemdetailsTest_usecase_1.output.json and paste the following JSON for the output:
{ "dfhcommarea":{ "itemNum":1000, "itemRecord":{ "itemName":"Kid Guitar", "description":"Kids Guitar - Musical Toys", "weight":200 }, "shipping":{ "shippingMethod":"AIR MAIL", "days":2 } } }
Open src/test/resources/mock/ItemdetailsTest/test_itemdetailsTest_usecase_2.input.json and change the itemNum field to 1004 for the input.
Open src/test/resources/mock/ItemdetailsTest/test_itemdetailsTest_usecase_2.output.json and paste the following JSON, for the output:

 {
    "dfhcommarea":{
       "itemNum":1004,
       "itemRecord":{
          "itemName":"Pig Bank",
          "description":"Pig Saving Bank - Ceramics",
          "weight":5000
       },
       "shipping":{
          "shippingMethod":"AIR MAIL",
          "days":2
       }
    }
 }

5. Run the JUnit by Right-Clicking on testItemdeEXECUTE → Run As → JUnit Tests. If you followed all the steps correctly the tests should pass.

Step 4 – Create an API and a SDK

Open the New Project Wizard:
- File → New → OpenLegacy API Project
Define the project name as as400-cobol-rpc-api.
Click at the Default Package field, to automatically fill it up.
Press Next and add the SDK project that was created in Step 1 as the reference project.
Right-Click on the as400-cobol-rpc-api project → OpenLegacy → Generate API from SDK
- Name the service ItemDetails.
- Select from the ItemDetails model the itemNum as input and change its name to itemNumber for better readability.
- Select ItemDetails model as output.
- Click OK

Step 5 - Run and Test your API

Right-Click on the as400-cobol-rpc-api project → OpenLegacy → Run Application
Open the browser on http://localhost:8080/swagger
Authorize through Oauth2
- Client Id: client_id
- Client Secret: client_secret
Click on the API we've created → Try it out
- Set dummy item Number as input (for example 1000).
- You should see a successful response returned directly from the AS/400 program FULLDETAIL
  { "itemdetails": { "itemNum": 1000, "itemRecord": { "itemName": "Kid Guitar", "description": "Kids Guitar - Musical Toys", "weight": 200 }, "shipping": { "shippingMethod": "AIR MAIL", "days": 2 } } }

OpenLegacy Training