example-invoice

The Camunda Invoice example in a Spring Boot Web Application

The Invoice example is provided in all of the pre-packaged distros that Camunda provides. This Camunda example provides the Invoice application inside a Spring Boot application together with all the necessary adjustments needed to run it out of the box. This includes:

• The Camunda EE Webapps
• The Camunda Rest API

You will need:

• credentials to access the enterprise repo in your settings.xml
• a valid camunda-license key file in your classpath in the file camunda-license.txt

Prerequisites

• Java 17/21

How is it done

1. To embed the Camunda Engine with the Enterprise webapps and Rest API you must add the following maven coordinates to your pom.xml:

...
  <properties>
    <camunda.version>7.22.0-ee</camunda.version>
  </properties>

  <dependencyManagement>
    <dependencies>
      ...
      <dependency>
        <groupId>org.camunda.bpm</groupId>
        <artifactId>camunda-bom</artifactId>
        <version>${camunda.version}</version>
        <type>pom</type>
        <scope>import</scope>
      </dependency>
    </dependencies>
  </dependencyManagement>

  <dependencies>
    <dependency>
      <groupId>org.camunda.bpm.springboot</groupId>
      <artifactId>camunda-bpm-spring-boot-starter-webapp-ee</artifactId>
    </dependency>
    <dependency>
      <groupId>org.camunda.bpm.springboot</groupId>
      <artifactId>camunda-bpm-spring-boot-starter-rest</artifactId>
    </dependency>
    ...
  </dependencies>
...

2. For the example Invoice application, the following dependency needs to be added in your pom.xml file:

<dependency>
  <groupId>org.camunda.bpm.example</groupId>
  <artifactId>camunda-example-invoice-jakarta</artifactId>
  <version>${camunda.version}</version>
  <classifier>classes</classifier>
  <scope>compile</scope>
</dependency>

3. An "application" class annotated with @SpringBootApplication needs to be created. In order to have the Invoice process application registered, add the annotation @EnableProcessApplication to the same class, as well as include an empty processes.xml file to your META-INF folder. To ensure that all of necessary BPMN and DMN files are deployed, add the following code in your "application" class:

@SpringBootApplication
@EnableProcessApplication
public class Application {

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

  @Autowired
  protected ProcessEngine processEngine;

  protected InvoiceProcessApplication invoicePa = new InvoiceProcessApplication();

  @PostConstruct
  public void deployInvoice() {
    ClassLoader classLoader = invoicePa.getClass().getClassLoader();

    if(processEngine.getIdentityService().createUserQuery().list().isEmpty()) {
      processEngine.getRepositoryService()
          .createDeployment()
          .addInputStream("invoice.v1.bpmn", classLoader.getResourceAsStream("invoice.v1.bpmn"))
          .addInputStream("reviewInvoice.bpmn", classLoader.getResourceAsStream("reviewInvoice.bpmn"))
          .deploy();
    }
  }

  @EventListener
  public void onPostDeploy(PostDeployEvent event) {
    invoicePa.startFirstProcess(event.getProcessEngine());
  }

}

4. You can also put additional BPMN, CMMN and DMN files in your classpath, they will be automatically deployed and registered within the process application. Forms HTML needs to be added in the /resources/static/forms directory.

5. If you want your Camunda license automatically used on Engine startup, just put the file with the name camunda-license.txt on your classpath.

6. Adjust the src/main/resources/application.yaml file according to your preferences. The default setup will use an embedded H2 instance.

Run the application and use Camunda Platform

You can build the application with mvn clean install and then run it with the java -jar command. You can also execute the application with mvn spring-boot:run.

Then you can access the Camunda Webapps in your browser: http://localhost:8080/ (provide login/password from application.yaml, default: demo/demo). The Rest API can be available through http://localhost:8080/engine-rest.