4.7. Adding Triggers to a Pipeline

Triggers enable Pipelines to respond to external GitHub events, such as push events and pull requests. After you have assembled and started the Pipeline for the application, add TriggerBindings, TriggerTemplates, and an EventListener to capture the GitHub events.

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: 

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

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

    $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-2/03_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-2
  - 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-$(params.git-repo-name)-$(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
        persistentvolumeclaim:
          claimName: source-pvc

  4. Create the TriggerTemplate: 

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

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

    $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-2/03_triggers/02_template.yaml

  5. 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:
  - bindings:
    - ref: vote-app
    template:
      name: vote-app

  6. Create the EventListener: 

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

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

    $ oc create -f https://raw.githubusercontent.com/openshift/pipelines-tutorial/release-tech-preview-2/03_triggers/03_event_listener.yaml

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

    $ oc expose svc el-vote-app