image-trigger-tekton

Triggering Tekton Pipelines as a result of changes of Image resources and delivered through the use of Knative Eventing

Overview

The contents of this repository demonstrates how to use a Knative ApiServerSource to trigger Tekton Pipelines when changes of OpenShift image events are received.

An overview of the architecture can be found below:

Prerequisites

The following prerequisites must be satisfied prior to deploying the solution contained within this repository

1. OpenShift and Tekton Command Line Interfaces
2. Access to an OpenShift Cluster with cluster-admin privileges
3. Installation of OpenShift Pipelines (Tekton)
4. Installation of OpenShift Serverless (Knative)
5. Installation of Knative Eventing

Installation

1. Create a new namespace called image-watcher and change the current content into the newly created namespace

kubectl apply -f namespace/image-watcher-namespace.yml
kubectl config set-context --current --namespace=image-watcher

2. Apply Tekton resources

kubectl apply -f pipelines

3. Apply Knative resources

kubectl apply -f knative

Validation

Verify the integration by building a new application and pushing it to the integrated OpenShift registry to trigger the Tekton pipeline.

First, create a new project called verify-image-trigger

oc new-project verify-image-trigger

Instantiate one of the included OpenShift templates to create an Django based application

oc new-app --template=django-psql-example

Track the status of the build that was automatically started

oc logs -n verify-image-trigger -f bc/django-psql-example

A new PipelineRun will have been triggered

tkn pipelinerun list -n image-watcher

View the logs from the PipelineRun

tkn pipelinerun logs -L -n image-watcher

[print-image : print-image] Event Type: dev.knative.apiserver.resource.add
[print-image : print-image] Image Name: sha256:3a2e3932987329f9a52e5ea41d820c9c6937125807850c5a98a48916c450962c
[print-image : print-image] Image Reference: image-registry.openshift-image-registry.svc:5000/verify-image-trigger/django-psql-example@sha256:3a2e3932987329f9a52e5ea41d820c9c6937125807850c5a98a48916c450962c