How can I make a Tekton Task's command execution wait until the previous Task's spun up pod is ready for requests

Question

I have an OpenShift/Tekton pipeline which in Task A deploys an application to a test environment. In Task B, the application's test suite is run. If all tests pass, then the application is deployed to another environment in Task C.

The problem is that Task A's pod is deployed (with oc apply -f <deployment>), and before the pod is actually ready to receive requests, Task B starts running the test suite, and all the tests fail (because it can't reach the endpoints defined in the test cases).

Is there an elegant way to make sure the pod from Task A is ready to receive requests, before starting the execution of Task B? One solution I have seen is to do HTTP GET requests against a health endpoint until you get a HTTP 200 response. We have quite a few applications which do not expose HTTP endpoints, so is there a more "generic" way to make sure the pod is ready? Can I for example query for a specific record in Task A's log? There is a log statement which always shows when the pod is ready to receive traffic.

If it's of any interest, here is the definition for Task A:

apiVersion: tekton.dev/v1beta1
kind: Task
metadata:
  name: create-and-deploy-integration-server
spec:
  params:
    - name: release-name
      type: string
      description: The release name of the application
    - name: image-name
      type: string
      description: The name of the container image to use
    - name: namespace
      type: string
      description: The namespace (OCP project) the application resides in
    - name: commit-id
      type: string
      description: The commit hash identifier for the current HEAD commit
  steps:
    - name: create-is-manifest
      image: image-registry.openshift-image-registry.svc:5000/openshift/origin-cli
      script: |
        echo "Creating IntegrationServer manifest"
        cat << EOF > integrationserver.yaml
        apiVersion: appconnect.ibm.com/v1beta1
        kind: IntegrationServer
        metadata:
          name: $(params.release-name)
          namespace: $(params.namespace)
        spec:
          license:
            accept: true
            license: L-KSBM-BZWEAT
            use: CloudPakForIntegrationNonProduction
          pod:
            containers:
              runtime:
                image: image-registry.openshift-image-registry.svc:5000/$(params.namespace)/$(params.image-name)-$(params.commit-id)
                imagePullPolicy: Always
                resources:
                  limits:
                    cpu: 500m
                    memory: 500Mi
                  requests:
                    cpu: 300m
                    memory: 300Mi
          adminServerSecure: true
          router:
            timeout: 120s
          designerFlowsOperationMode: disabled
          service:
            endpointType: http
          version: 11.0.0.11-r2
          replicas: 1
          barURL: ''
        EOF
    - name: deploy-is-manifest
      image: image-registry.openshift-image-registry.svc:5000/openshift/origin-cli
      script: |
        echo "Applying IntegrationServer manifest to OpenShift cluster"
        oc apply -f integrationserver.yaml

Answer 1

After your step that do oc apply, you can add a step to wait for the deployment to become "available". This is for kubectl but should work the same way with oc:

kubectl wait --for=condition=available --timeout=60s deployment/myapp

Then the next Task can depend on this Task with runAfter: ["create-and-deploy-integration-server"]