Create the Test Runner Microservice

Next, you will create the “Test Runner” microservice which you will use to simulate the ATM and Back Office. This service will send messages to the queues that you just created.

Create a new Java Project for the transfer service.

In the Explorer of VS Code open Java Project and click the plus sign to add a Java Project to your workspace.

Select Spring Boot Project.

Select Maven Project.

Specify 3.3.4 as the Spring Boot version.

Use com.example as the Group Id.

Enter testrunner as the Artifact Id.

Use JAR as the Packaging Type.

Select Java version 21.

Search for Spring Web and press Enter

Press Enter to continue and create the Java Project

Select the root location for your project e.g. side by side with the account project.

When the project opens click Add to Workspace

Modify the pom.xml file

Open the pom.xml file in the testrunner project. This service will use the “Web” Spring Boot Starter which will allow it to expose REST endpoints and make REST calls to other services. It also uses the two Oracle Spring Boot Starters for UCP and Wallet to access the database: Add the following to the pom.xml:

  <dependency>
    <groupId>com.oracle.database.spring</groupId>
    <artifactId>oracle-spring-boot-starter-aqjms</artifactId>
    <version>23.4.0</version>
  </dependency>
  <dependency>
    <groupId>com.oracle.database.spring</groupId>
    <artifactId>oracle-spring-boot-starter-wallet</artifactId>
    <type>pom</type>
    <version>23.4.0</version>
  </dependency>
  <dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
  </dependency>

Create the Spring Boot application YAML file

In the testrunner project, rename the file called application.properties to application.yaml located in the src/main/resources. This will be the Spring Boot application configuration file:
```
spring:
  application:
    name: testrunner

  datasource:
    url: ${spring.datasource.url}
    username: ${spring.datasource.username}
    password: ${spring.datasource.password}
```
This is the Spring Boot application YAML file, which contains the configuration information for this service. In this case, you only need to provide the application name and the connection details for the database hosting the queues.
Create the main Spring Application class

In the testrunner directory, open the Java file called TestrunnerApplication.java and add this content. This is a standard Spring Boot main class, notice the @SpringBootApplication annotation on the class. It also has the @EnableJms annotation which tells Spring Boot to enable JMS functionality in this application. The main method is a normal Spring Boot main method:
```
package com.example.testrunner;

import jakarta.jms.ConnectionFactory;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.jms.annotation.EnableJms;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.jms.support.converter.MappingJackson2MessageConverter;
import org.springframework.jms.support.converter.MessageConverter;
import org.springframework.jms.support.converter.MessageType;

@SpringBootApplication
@EnableJms
public class TestrunnerApplication {

    public static void main(String[] args) {
        SpringApplication.run(TestrunnerApplication.class, args);
    }

    // Serialize message content to json using TextMessage
    @Bean 
    public MessageConverter jacksonJmsMessageConverter() {
        MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
        converter.setTargetType(MessageType.TEXT);
        converter.setTypeIdPropertyName("_type");
        return converter;
    }

    @Bean 
    public JmsTemplate jmsTemplate(ConnectionFactory connectionFactory) {
        JmsTemplate jmsTemplate = new JmsTemplate();
        jmsTemplate.setConnectionFactory(connectionFactory);
        jmsTemplate.setMessageConverter(jacksonJmsMessageConverter());
        return jmsTemplate;
    }

}
```
In addition to the standard parts of a Spring Boot application class, you will add two beans that will be needed in this service. First, you need a MessageConverter bean so that you can convert a Java object (POJO) into JSON format, and vice versa. This bean will be used to serialize and deserialize the objects you need to write onto the queues.

The second bean you need is a JmsTemplate. This is a standard Spring JMS bean that is used to access JMS functionality. You will use this bean to enqueue messages. Notice that this bean is configured to use the MessageConverter bean and that the JMS ConnectionFactory is injected. The Oracle Spring Boot Starter for AQ/JMS will create the JMS ConnectionFactory for you.

Note: The Oracle Spring Boot Starter for AQ/JMS will also inject a JDBC Connection bean which shares the same database transaction with the JMS ConnectionFactory. This is not needed in this lab. The shared transaction enables you to write methods which can perform both JMS and JPA operations in an atomic transaction, which can be very helpful in some use cases and can dramatically reduce the amount of code needed to handle situations like duplicate message delivery or lost messages.

Create the model classes

Create a new directory called src/main/java/com/example/testrunner/model and in this directory create two Java files. First, CheckDeposit.java with this content. This class will be used to simulate the ATM sending the “deposit” notification:

package com.example.testrunner.model;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class CheckDeposit {
    private long accountId;
    private long amount;
}

Next, Clearance.java with this content. This class will be used to simulate the Back Office sending the “clearance” notification:

package com.example.testrunner.model;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Clearance {
    private long journalId;
}

Create the controller

Create a new directory called src/main/java/com/example/testrunner/controller and in this directory create a new Java file called TestRunnerController.java with the following content. This class will have the RestController annotation so that it can expose REST APIs that you can call to trigger the simulation of the ATM and Back Office notifications. It will need the JmsTemplate to access JMS functionality, this can be injected with the AutoWired annotation. Create two methods, one to send each notification:

package com.example.testrunner.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.jms.core.JmsTemplate;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.example.testrunner.model.CheckDeposit;
import com.example.testrunner.model.Clearance;

@RestController
@RequestMapping("/api/v1/testrunner")
public class TestRunnerController {

    @Autowired
    private JmsTemplate jmsTemplate;

    @PostMapping("/deposit")
    public ResponseEntity<CheckDeposit> depositCheck(@RequestBody CheckDeposit deposit) {       
        jmsTemplate.convertAndSend("deposits", deposit);
        return new ResponseEntity<CheckDeposit>(deposit, HttpStatus.CREATED);
    }

    @PostMapping("/clear")
    public ResponseEntity<Clearance> clearCheck(@RequestBody Clearance clearance) {
        jmsTemplate.convertAndSend("clearances", clearance);
        return new ResponseEntity<Clearance>(clearance, HttpStatus.CREATED);
    }

}

Build a JAR file for deployment

Run the following command to build the JAR file.
```
$ mvn clean package -DskipTests
```
The service is now ready to deploy to the backend.

Prepare the backend for deployment

The Oracle Backend for Microservices and AI admin service is not exposed outside the Kubernetes cluster by default. Oracle recommends using a kubectl port forwarding tunnel to establish a secure connection to the admin service.

Start a tunnel using this command in a new terminal window:

$ kubectl -n obaas-admin port-forward svc/obaas-admin 8080

Get the password for the obaas-admin user. The obaas-admin user is the equivalent of the admin or root user in the Oracle Backend for Microservices and AI backend.

$ kubectl get secret -n azn-server  oractl-passwords -o jsonpath='{.data.admin}' | base64 -d

Start the Oracle Backend for Microservices and AI CLI (oractl) in a new terminal window using this command:

$ oractl
 _   _           __    _    ___
/ \ |_)  _.  _. (_    /  |   |
\_/ |_) (_| (_| __)   \_ |_ _|_
========================================================================================
  Application Name: Oracle Backend Platform :: Command Line Interface
  Application Version: (1.3.0)
  :: Spring Boot (v3.3.3) ::

  Ask for help:
  - Slack: https://oracledevs.slack.com/archives/C03ALDSV272
  - email: obaas_ww@oracle.com

oractl:>

Connect to the Oracle Backend for Microservices and AI admin service using the connect command. Enter obaas-admin and the username and use the password you collected earlier.

oractl> connect
username: obaas-admin
password: **************
Credentials successfully authenticated! obaas-admin -> welcome to OBaaS CLI.
oractl:>

Create a binding for the Test Runner service

Create a binding so the Test Runner service can access the Oracle Autonomous Database as the account user. Run this command to create the binding, and type in the password for the account user when prompted. The password is Welcome1234##:
```
oractl:> bind --app-name application --service-name testrunner --username account
```
Deploy the Test Runner service

You will now deploy your Test Runner service to the Oracle Backend for Microservices and AI using the CLI. Run this command to deploy your service, make sure you provide the correct path to your JAR file. Note that this command may take 1-3 minutes to complete:
```
oractl:> deploy --app-name application --service-name testrunner --artifact-path /path/to/testrunner-0.0.1-SNAPSHOT.jar --image-version 0.0.1 --java-version ghcr.io/oracle/graalvm-native-image-obaas:21
uploading: testrunner/target/testrunner-0.0.1-SNAPSHOT.jarbuilding and pushing image...
creating deployment and service... successfully deployed
oractl:>
```
You can close the port forwarding session for the CLI now (just type a Ctrl+C in its console window).

Check that the testrunner service is running

Verify that the testrunner application is up and running by running this command:

$ kubectl logs -n application svc/testrunner

The output should be similar to this, look for Started TestrunnerApplication

2023-06-02 15:18:39.620  INFO 1 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1806 ms
2023-06-02 15:18:40.915  INFO 1 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port(s): 8080 (http) with context path ''
2023-06-02 15:18:40.938  INFO 1 --- [           main] c.e.testrunner.TestrunnerApplication     : Started TestrunnerApplication in 4.174 seconds (JVM running for 5.237)

Test the endpoints

The Test Runner service is not exposed outside your Kubernetes cluster, so you must create a port-forwarding tunnel to access it. Create a tunnel using this command:

$ kubectl -n application port-forward svc/testrunner 8084:8080

Call the deposit endpoint to send a deposit notification using this command:

$ curl -i -X POST -H 'Content-Type: application/json' -d '{"accountId": 2, "amount": 200}' http://localhost:8084/api/v1/testrunner/deposit
HTTP/1.1 201
Date: Wed, 31 May 2023 15:11:55 GMT
Content-Type: application/json
Transfer-Encoding: chunked
Connection: keep-alive

{"accountId":2,"amount":200}

Call the clear endpoint to send a clearance notification using this command. Note that you can use any journalId since there is nothing receiving and processing these messages yet:

$ curl -i -X POST -H 'Content-Type: application/json' -d '{"journalId": 4}' http://localhost:8084/api/v1/testrunner/clear
HTTP/1.1 201
Date: Wed, 31 May 2023 15:12:54 GMT
Content-Type: application/json
Transfer-Encoding: chunked
Connection: keep-alive

{"journalId":4}

Verify the expected messages are on the queues

Connect to the database as the account (password Welcome12343##) and issue this SQL statement to check the payloads of the messages on the deposits queue:
```
SQL> select qt.user_data.text_vc from deposits_qt qt;

USER_DATA.TEXT_VC
_______________________________
{"accountId":2,"amount":200}
```
Issue this SQL statement to check the payloads of the messages on the clearances queue:
```
SQL> select qt.user_data.text_vc from clearances_qt qt;

USER_DATA.TEXT_VC
____________________
{"journalId":4}
```
That completes the Test Runner service. Next, you will build the Check Processing service which will receive these messages and process them.