multiple-apps.md

Control the delivery process of multiple applications

Apply the following workflow to control the delivery process of multiple applications:

apiVersion: core.oam.dev/v1alpha1
kind: WorkflowRun
metadata:
  name: apply-applications
  namespace: default
  annotations:
    workflowrun.oam.dev/debug: "true"
spec:
  workflowSpec:
    steps:
      - name: check-app-exist
        type: read-app
        properties:
          name: webservice-app
      - name: apply-app1
        type: apply-app
        if: status["check-app-exist"].message == "Application not found"
        properties:
          data:
            apiVersion: core.oam.dev/v1beta1
            kind: Application
            metadata:
              name: webservice-app
            spec:
              components:
                - name: express-server
                  type: webservice
                  properties:
                    image: crccheck/hello-world
                    ports:
                      - port: 8000
      - name: suspend
        type: suspend
        timeout: 24h
      - name: apply-app2
        type: apply-app
        properties:
          ref:
            name: my-app
            key: application
            type: configMap
---
apiVersion: v1
kind: ConfigMap
metadata:
  name: my-app
  namespace: default
data:
  application: |
    apiVersion: core.oam.dev/v1beta1
    kind: Application
    metadata:
      name: webservice-app2
    spec:
      components:
        - name: express-server2
          type: webservice
          properties:
            image: crccheck/hello-world
            ports:
              - port: 8000

Above workflow will first try to read the Application called webservice-app from the cluster, if the Application is not found, this step's status message will be Application not found. The second step will deploy the webservice-app Application if webservice-app is not exist in the cluster. After that, the suspend step will suspend the delivery process for manual approve.

$ kubectl get wr
NAME                 PHASE        AGE
apply-applications   suspending   2s

You can use vela workflow resume to resume this workflow, note that if the workflow has not been resumed in 24 hours, the workflow will failed of timeout:

vela workflow resume apply-applications

After the workflow is resumed, it will deploy an another Application from the data in ConfigMap with key application.