Chapter 4. Creating CI/CD solutions for applications using OpenShift Pipelines

Procedure

1. Log in to your OpenShift Container Platform cluster:

   $ oc login -u <login> -p <password> https://openshift.example.com:6443

2. Create a project for the sample application. For this example workflow, create the pipelines-tutorial project:

   $ oc new-project pipelines-tutorial

   Note

   If you create a project with a different name, be sure to update the resource URLs used in the example with your project name.

3. View the pipeline ServiceAccount:

   Red Hat OpenShift Pipelines Operator adds and configures a ServiceAccount named pipeline that has sufficient permissions to build and push an image. This ServiceAccount is used by PipelineRun.

   $ oc get serviceaccount pipeline

Procedure

1. Install the apply-manifests and update-deployment Task resources from the pipelines-tutorial repository, which contains a list of reusable tasks for pipelines:

   $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-3/01_pipeline/01_apply_manifest_task.yaml
   $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-3/01_pipeline/02_update_deployment_task.yaml

2. Use the tkn task list command to list the tasks you created:

   $ tkn task list

   The output verifies that the apply-manifests and update-deployment Task resources were created:

   NAME                DESCRIPTION   AGE
   apply-manifests                   1 minute ago
   update-deployment                 48 seconds ago

3. Use the tkn clustertasks list command to list the Operator-installed additional ClusterTask resources, for example --buildah and s2i-python-3:

   Note

   You must use a privileged pod container to run the buildah ClusterTask resource because it requires a privileged security context. To learn more about security context constraints (SCC) for pods, see the Additional resources section.

   $ tkn clustertasks list

   The output lists the Operator-installed ClusterTask resources:

   NAME                       DESCRIPTION   AGE
   buildah                                  1 day ago
   git-clone                                1 day ago
   s2i-php                                  1 day ago
   tkn                                      1 day ago

Procedure

1. Copy the contents of the following sample Pipeline YAML file and save it:

   apiVersion: tekton.dev/v1beta1
   kind: Pipeline
   metadata:
     name: build-and-deploy
   spec:
     workspaces:
     - name: shared-workspace
     params:
     - name: deployment-name
       type: string
       description: name of the deployment to be patched
     - name: git-url
       type: string
       description: url of the git repo for the code of deployment
     - name: git-revision
       type: string
       description: revision to be used from repo of the code for deployment
       default: "release-tech-preview-3"
     - name: IMAGE
       type: string
       description: image to be built from the code
     tasks:
     - name: fetch-repository
       taskRef:
         name: git-clone
         kind: ClusterTask
       workspaces:
       - name: output
         workspace: shared-workspace
       params:
       - name: url
         value: $(params.git-url)
       - name: subdirectory
         value: ""
       - name: deleteExisting
         value: "true"
       - name: revision
         value: $(params.git-revision)
     - name: build-image
       taskRef:
         name: buildah
         kind: ClusterTask
       params:
       - name: TLSVERIFY
         value: "false"
       - name: IMAGE
         value: $(params.IMAGE)
       workspaces:
       - name: source
         workspace: shared-workspace
       runAfter:
       - fetch-repository
     - name: apply-manifests
       taskRef:
         name: apply-manifests
       workspaces:
       - name: source
         workspace: shared-workspace
       runAfter:
       - build-image
     - name: update-deployment
       taskRef:
         name: update-deployment
       workspaces:
       - name: source
         workspace: shared-workspace
       params:
       - name: deployment
         value: $(params.deployment-name)
       - name: IMAGE
         value: $(params.IMAGE)
       runAfter:
       - apply-manifests

   The Pipeline definition abstracts away the specifics of the Git source repository and image registries. These details are added as params when a Pipeline is triggered and executed.

2. Create the Pipeline:

   $ oc create -f <pipeline-yaml-file-name.yaml>

   Alternatively, you can also execute the YAML file directly from the Git repository:

   $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-3/01_pipeline/04_pipeline.yaml

3. Use the tkn pipeline list command to verify that the Pipeline is added to the application:

   $ tkn pipeline list

   The output verifies that the build-and-deploy Pipeline was created:

   NAME               AGE            LAST RUN   STARTED   DURATION   STATUS
   build-and-deploy   1 minute ago   ---        ---       ---        ---

Procedure

1. Start the pipeline for the back-end application:

   $ tkn pipeline start build-and-deploy \
       -w name=shared-workspace,volumeClaimTemplateFile=https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-3/01_pipeline/03_persistent_volume_claim.yaml \
       -p deployment-name=vote-api \
       -p git-url=http://github.com/openshift-pipelines/vote-api.git \
       -p IMAGE=image-registry.openshift-image-registry.svc:5000/pipelines-tutorial/vote-api \

   The previous command uses a volume claim template, which creates a persistent volume claim for the pipeline execution.

2. To track the progress of the pipeline run, enter the following command::

   $ tkn pipelinerun logs <pipelinerun_id> -f

   The <pipelinerun_id> in the above command is the ID for the PipelineRun that was returned in the output of the previous command.

3. Start the Pipeline for the front-end application:

   $ tkn pipeline start build-and-deploy \
       -w name=shared-workspace,volumeClaimTemplateFile=https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-3/01_pipeline/03_persistent_volume_claim.yaml \
       -p deployment-name=vote-ui \
       -p git-url=http://github.com/openshift-pipelines/vote-ui.git \
       -p IMAGE=image-registry.openshift-image-registry.svc:5000/pipelines-tutorial/vote-ui \

4. To track the progress of the pipeline run, enter the following command:

   $ tkn pipelinerun logs <pipelinerun_id> -f

   The <pipelinerun_id> in the above command is the ID for the PipelineRun that was returned in the output of the previous command.

5. After a few minutes, use tkn pipelinerun list command to verify that the Pipeline ran successfully by listing all the PipelineRuns:

   $ tkn pipelinerun list

   The output lists the PipelineRuns:

    NAME                         STARTED      DURATION     STATUS
    build-and-deploy-run-xy7rw   1 hour ago   2 minutes    Succeeded
    build-and-deploy-run-z2rz8   1 hour ago   19 minutes   Succeeded

6. Get the application route:

   $ oc get route vote-ui --template='http://{{.spec.host}}'

   Note the output of the previous command. You can access the application using this route.

7. To rerun the last pipeline run, using the pipeline resources and service account of the previous pipeline, run:

   $ tkn pipeline start build-and-deploy --last

Procedure

1. Copy the content of the following sample TriggerBinding YAML file and save it:

   apiVersion: triggers.tekton.dev/v1alpha1
   kind: TriggerBinding
   metadata:
     name: vote-app
   spec:
     params:
     - name: git-repo-url
       value: $(body.repository.url)
     - name: git-repo-name
       value: $(body.repository.name)
     - name: git-revision
       value: $(body.head_commit.id)

2. Create the TriggerBinding resource:

   $ oc create -f <triggerbinding-yaml-file-name.yaml>

   Alternatively, you can create the TriggerBinding resource directly from the pipelines-tutorial Git repository:

   $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-3/03_triggers/01_binding.yaml

3. Copy the content of the following sample TriggerTemplate YAML file and save it:

   apiVersion: triggers.tekton.dev/v1alpha1
   kind: TriggerTemplate
   metadata:
     name: vote-app
   spec:
     params:
     - name: git-repo-url
       description: The git repository url
     - name: git-revision
       description: The git revision
       default: release-tech-preview-3
     - name: git-repo-name
       description: The name of the deployment to be created / patched
   
     resourcetemplates:
     - apiVersion: tekton.dev/v1beta1
       kind: PipelineRun
       metadata:
         name: build-deploy-$(tt.params.git-repo-name)-$(uid)
       spec:
         serviceAccountName: pipeline
         pipelineRef:
           name: build-and-deploy
         params:
         - name: deployment-name
           value: $(tt.params.git-repo-name)
         - name: git-url
           value: $(tt.params.git-repo-url)
         - name: git-revision
           value: $(tt.params.git-revision)
         - name: IMAGE
           value: image-registry.openshift-image-registry.svc:5000/pipelines-tutorial/$(tt.params.git-repo-name)
         workspaces:
         - name: shared-workspace
           volumeClaimTemplate:
             spec:
               accessModes:
                 - ReadWriteOnce
               resources:
                 requests:
                   storage: 500Mi

   The template specifies a volume claim template to create a persistent volume claim for defining the storage volume for the workspace. Therefore, you do not need to create a persistent volume claim to provide data storage.

4. Create the TriggerTemplate resource:

   $ oc create -f <triggertemplate-yaml-file-name.yaml>

   Alternatively, you can create the TriggerTemplate resource directly from the pipelines-tutorial Git repository:

   $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-3/03_triggers/02_template.yaml

5. Copy the contents of the following sample Trigger YAML file and save it:

   apiVersion: triggers.tekton.dev/v1alpha1
   kind: Trigger
   metadata:
     name: vote-trigger
   spec:
     serviceAccountName: pipeline
     bindings:
       - ref: vote-app
     template:
        name: vote-app

6. Create the Trigger resource:

   $ oc create -f <trigger-yaml-file-name.yaml>

   Alternatively, you can create the Trigger resource directly from the pipelines-tutorial Git repository:

   $ oc create -f https://github.com/openshift/pipelines-tutorial/blob/release-tech-preview-3/03_triggers/03_trigger.yaml

7. Copy the contents of the following sample EventListener YAML file and save it:

   apiVersion: triggers.tekton.dev/v1alpha1
   kind: EventListener
   metadata:
     name: vote-app
   spec:
     serviceAccountName: pipeline
     triggers:
       - triggerRef: vote-trigger

   Alternatively, if you have not defined a trigger custom resource, add the binding and template spec to the EventListener YAML file, instead of referring to the name of the trigger:

   apiVersion: triggers.tekton.dev/v1alpha1
   kind: EventListener
   metadata:
     name: vote-app
   spec:
     serviceAccountName: pipeline
     triggers:
     - bindings:
       - ref: vote-app
       template:
         name: vote-app

8. Create the EventListener resource:

   $ oc create -f <eventlistener-yaml-file-name.yaml>

   Alternatively, you can create the EvenListener resource directly from the pipelines-tutorial Git repository:

   $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-3/03_triggers/04_event_listener.yaml

9. Expose the EventListener service as an OpenShift Container Platform route to make it publicly accessible:

   $ oc expose svc el-vote-app

Procedure

1. Get the Webhook URL:

   $ echo "URL: $(oc  get route el-vote-app --template='http://{{.spec.host}}')"

   Note the URL obtained in the output.

2. Configure Webhooks manually on the front-end repository:

   1. Open the front-end Git repository vote-ui in your browser.
   2. Click Settings Webhooks Add Webhook

   3. On the Webhooks/Add Webhook page:

      1. Enter the Webhook URL from step 1 in Payload URL field
      2. Select application/json for the Content type
      3. Specify the secret in the Secret field
      4. Ensure that the Just the push event is selected
      5. Select Active
      6. Click Add Webhook
3. Repeat step 2 for the back-end repository vote-api.

Procedure

1. From the terminal, clone your forked Git repository vote-ui:

   $ git clone git@github.com:<your GitHub ID>/vote-ui.git -b release-tech-preview-3

2. Push an empty commit:

   $ git commit -m "empty-commit" --allow-empty && git push origin release-tech-preview-3

3. Check if the pipeline run was triggered:

   $ tkn pipelinerun list

   Notice that a new pipeline run was initiated.