Using Camunda Cloud, you can orchestrate the microservices necessary to achieve your end-to-end automated business process. Whether you have existing microservices or are looking to build out your microservices, this guide will help you understand how you can start your microservice orchestration journey with Camunda Cloud.
While this guide uses code snippets in Java, you do not need to be a Java developer to be successful. Additionally, you can orchestrate microservices with Camunda Cloud in other programming languages.
- Valid Camunda Cloud account or sign up if you still need one
- Java >= 8
- IDE (IntelliJ, VSCode, or similar)
- Download and unzip or clone the repo, then
- Design your process with BPMN
- Create credentials for your Zeebe client
- Create a worker for the service task
Start by designing your automated process using BPMN. This guide introduces you to the palette and a few BPMN symbols in Cloud Modeler.
- Navigate to your diagrams, either through the Diagrams navigation, or by using the section under Camunda Cloud Service on the main dashboard. Click Create New Diagram. This opens Cloud Modeler.
- Give your model a descriptive name and id. For this guide, we'll use Microservice Orchestration Tutorial for the name and microservice-orchestration-tutorial for the id.
- Use Cloud Modeler to design a BPMN process with service tasks. These service tasks are used to call your microservices via workers. Create a service task by dragging the task icon from the palette, or by clicking the existing start event and clicking the task icon. Change the task type by clicking the wrench icon and selecting Service Task.
- Add a descriptive name using the properties panel. For this guide, we'll use Microservice Example.
- Use the Type field to enter a string used in connecting this service task to the corresponding microservice code. For this guide, we'll use orchestrate-something as the type. You will use this in Create a worker for the service task. If you do not have an option to add the Type, make sure you have used the wrench icon and selected Service Task.
- Add an end event by dragging one from the palette, or by clicking the end event when the last service task in your diagram has focus. The linter should turn green with a checkmark and show zero errors and zero warnings.
- In the Execute drop down, click Save and Deploy. Your diagram is now deployed to your cluster.
- Start a new process instance in the Execute drop down by clicking Start Instance.
- In the Execute drop down, click View Process Instances. Navigate to Operate to see your process instance with a token waiting at the service task.
To interact with your Camunda Cloud cluster, you'll use the Zeebe client. First, you'll need to create credentials.
- Navigate to your clusters either through the navigation Clusters or by using the section under Camunda Cloud Service on the main dashboard. Click on your existing cluster. This will open the Overview for your cluster, where you can find your cluster id and region. You will need this information later when creating a worker in the next section.
If your account is new, you should have a cluster already available. If no cluster is available, or you’d like to create a new one, click Create New Cluster.
- Navigate to the API tab. Click Create.
- Provide a descriptive name for your client like
microservice-worker. For this tutorial, the scope can be the default Zeebe scope. Click Create.
- Your client credentials can be copied or downloaded at this point. You will need your client id and your client secret when creating a worker in the next section, so keep this window open. Once you close or navigate away from this screen, you will not be able to see them again.
Next, we’ll create a worker for the service task by associating it with the type we specified on the service task in the BPMN diagram.
- Open the downloaded or cloned project (repo, then
camunda-cloud-tutorials/orchestrate-microservices/worker-java) in your IDE .
- Add your credentials to
application.properties. Your client id and client secret are available from the previous section in the credential text file you downloaded or copied. Your cluster id and region can be found by going to the cluster overview page.
- In the
Worker.javafile, change the type to match what you specified in the BPMN diagram. If you followed the previous steps for this guide and entered “orchestrate-something”, no action is required.
- After making these changes, perform a Maven install, then run the Worker.java
mainmethod via your favorite IDE. If you prefer using a terminal, run
mvn package exec:java.
- Navigate to Operate and you will see your token has moved to the end event, completing this process instance.
Congratulations! You successfully built your first microservice orchestration solution with Camunda Cloud.