Appendix B. Updating the deployment configuration of an example application

The deployment configuration for an example application contains information related to deploying and running the application in OpenShift, such as route information or readiness probe location. The deployment configuration of an example application is stored in a set of YAML files. For examples that use the Fabric8 Maven Plugin, the YAML files are located in the src/main/fabric8/ directory. For examples using Nodeshift, the YAML files are located in the .nodeshift directory.

Important

The deployment configuration files used by the Fabric8 Maven Plugin and Nodeshift do not have to be full OpenShift resource definitions. Both Fabric8 Maven Plugin and Nodeshift can take the deployment configuration files and add some missing information to create a full OpenShift resource definition. The resource definitions generated by the Fabric8 Maven Plugin are available in the target/classes/META-INF/fabric8/ directory. The resource definitions generated by Nodeshift are available in the tmp/nodeshift/resource/ directory.

Prerequisites

  • An existing example project.
  • The oc CLI client installed.

Procedure

  1. Edit an existing YAML file or create an additional YAML file with your configuration update.

    • For example, if your example already has a YAML file with a readinessProbe configured, you could change the path value to a different available path to check for readiness:

      spec:
        template:
          spec:
            containers:
              readinessProbe:
                httpGet:
                  path: /path/to/probe
                  port: 8080
                  scheme: HTTP
      ...
    • If a readinessProbe is not configured in an existing YAML file, you can also create a new YAML file in the same directory with the readinessProbe configuration.
  2. Deploy the updated version of your example using Maven or npm.
  3. Verify that your configuration updates show in the deployed version of your example.

    $ oc export all --as-template='my-template'
    
    apiVersion: v1
    kind: Template
    metadata:
      creationTimestamp: null
      name: my-template
    objects:
    - apiVersion: v1
      kind: DeploymentConfig
      ...
      spec:
        ...
        template:
          ...
          spec:
            containers:
              ...
              livenessProbe:
                failureThreshold: 3
                httpGet:
                  path: /path/to/different/probe
                  port: 8080
                  scheme: HTTP
                initialDelaySeconds: 60
                periodSeconds: 30
                successThreshold: 1
                timeoutSeconds: 1
              ...

Additional resources

If you updated the configuration of your application directly using the web-based console or the oc CLI client, export and add these changes to your YAML file. Use the oc export all command to show the configuration of your deployed application.