payment-example-process-application

Payment Example Process Application

This is an example of a process application containing a payment process and the required workers, forms and dummy services.

You can use the image that is build from this spring boot application to have first running example in your Self-managed installation of a Camunda 8 cluster.

Features

• Auto deployment of the BPMN file when the application starts.
• Form to start process instances manually
• REST Api to start process instance (scripted by yourself)
• Workers with business logic included

Use the application

The application is provided as a container image here: https://github.com/camunda-community-hub/camunda-8-examples/pkgs/container/camunda-8-examples%2Fpayment-example-process-application

You can pull it from here:

docker pull ghcr.io/camunda-community-hub/camunda-8-examples/payment-example-process-application:latest

Kubernetes Deployment Tutorial

To deploy this Payment Example Process Application on Kubernetes, follow the detailed tutorial available here.

Build the image

mvn clean install

Requirements: Docker daemon on the build computer (https://docs.spring.io/spring-boot/docs/current/maven-plugin/reference/htmlsingle/#build-image).

Configuration

As the image contains the Spring-Zeebe client, you can configure all required connection properties as described here: https://github.com/camunda-community-hub/spring-zeebe#configuring-camunda-platform-8-saas-connection. Spring Boot offers configuration over environment variables: https://docs.spring.io/spring-boot/docs/current/reference/html/features.html#features.external-config

The application.yaml, that is included in the image, contains values for local development.

camunda:
  client:
    mode: selfmanaged

Maybe you have to override the values in your cluster.

Using a Camunda 8 SaaS cluster

If you want to connect the container to a Camunda 8 cloud cluster, the docker command looks like this:

docker run -e CAMUNDA_CLIENT_MODE=saas -e CAMUNDA_CLIENT_AUTH_CLIENTID -e CAMUNDA_CLIENT_AUTH_CLIENTSECRET -e CAMUNDA_CLIENT_REGION -e CAMUNDA_CLIENT_CLUSTERID -p 8080:8080 --name payment-example-process-application payment-example-process-application:0.0.1-SNAPSHOT

The environment variables were set in the shell before.

Running

The application exposes a webserver on port 8080 with an HTML page containing a form to request a payment.

Conventions for this application:

• The customer ID should end with a number (cust45). The number is the credit that the customer already has with the company.
• If the customer credit is higher than the order total, there is no additional credit card charge required.
• If the customer credit is not sufficient to cover the order total, the remaining amount is charged from the credit card.
• If the credit card expired or has an invalid expiry date, a user has to decide via Tasklist, if the payment error can be resolved or not.

You can start a process instance with REST call as well:

curl -L "http://localhost:8080/start" -X "POST" -H "Content-Type: application/json" -d "{\"customerId\": \"cust50\", \"orderTotal\": 67.50, \"cardNumber\": \"1234 4567\", \"cvc\": \"123\", \"expiryDate\": \"12/24\"}"

Interaction with business logic

The application writes the interaction of process instances with the business logic into the container log. There you can find output like this:

Handling customer credit for process instance 2251799813720515
customer cust50 has credit of 50.0
charged 50.0 from the credit, open amount is 17.5
Handling credit card payment for process instance 2251799813720515
charging card 1234 4567 that expires on 12/24 and has cvc 123 with amount of 17.5
payment completed