To get started with Triggers, let's put it to work building and deploying a real image. In the following guide, we will use Triggers
to handle a real GitHub webhook request to kickoff a PipelineRun.
Before we can use the Triggers project, we need to get some dependencies out of the way.
- A Kubernetes Cluster
- This guide depends on an having access to a Kubernetes cluster which is publicly reachable from the internet.
- The cluster also needs the ability to create ingress resources.
- Most cloud providers k8s offerings work for this purpose...
- but ingress does not work out of the box for GKE clusters.
- For now, GKE users should consider using the nginx ingress.
- Install Tekton Pipelines
- Pipelines is the backbone of Tekton and will allow us to accomplish the work we plan to do.
- Install Triggers
- Of course we need to install our project as well, so we can accept and process events into PipelineRuns!
- Pick a GitHub repo with a Dockerfile as your build object (or you can fork this one).
- Clone this repo locally - we will come back to this repo later.
Now that we have our cluster ready, we need to setup our getting-started namespace and RBAC. We will keep everything inside this single namespace for easy cleanup. In the unlikely event that you get stuck/flummoxed, the best course of action might be to just delete this namespace and start fresh.
- Create the getting-started namespace, where all our resources will live.
kubectl create namespace getting-started
- Create the admin user, role and rolebinding
kubectl apply -f ./docs/getting-started/rbac/admin-role.yaml
- Create the create-webhook user, role and rolebinding
kubectl apply -f ./docs/getting-started/rbac/webhook-role.yaml
- This will allow our webhook to create the things it needs to.
Now we have to install the Pipeline we plan to use and also our Triggers resources.
kubectl apply -f ./docs/getting-started/pipeline.yaml
Our Pipeline will do a few things.
- Retrieve the source code
- Build and push the source code into a Docker image
- Push the image to the specified repository
- Run the image locally
The Pipeline will build a Docker image with img and deploy it locally via kubectl image.
The Triggers project will pickup from there.
- We will setup an
EventListener
to accept and process GitHub Push events - A
TriggerTemplate
to create templated PipelineResource and PipelineRun resources per event received by theEventListener
.- First, update the
triggers.yaml
file to reflect the Docker repository you wish to push the image blob to. - You will need to replace the
DOCKERREPO-REPLACEME
string everywhere it is needed. - Once you have updated the triggers file, you can apply it!
kubectl apply -f ./docs/getting-started/triggers.yaml
- If that succeeded, your cluster is ready to start handling Events.
- First, update the
We will need an ingress to handle incoming webhooks and we will make use of our new ingress by configuring Github with our GitHub Task.
First lets create our ingress Task.
kubectl apply -f ./docs/create-ingress.yaml -n getting-started
Now lets create our webhook Task.
kubectl apply -f ./docs/create-webhook.yaml -n getting-started
Note: If you are running on GKE, the default Ingress will not work. Instead, follow the instructions to use an Nginx Ingress here
Lets first update the TaskRun to make any needed changes
Edit the docs/getting-started/ingress-run.yaml
file to adjust the settings.
At the mimimum, you will need to update the ExternalDomain field to match your own DNS name.
When you are ready, run the ingress Task.
kubectl apply -f docs/getting-started/ingress-run.yaml
You will need to create a Github Personal Access Token with the following access.
public_repo
admin:repo_hook
Next, create a secret like so with your access token.
apiVersion: v1
kind: Secret
metadata:
name: webook-secret
namespace: getting-started
stringData:
token: YOUR-GITHUB-ACCESS-TOKEN
secret: random-string-data
Now lets update the GitHub Task run.
There are a few fields to change, but these fields must be updated at the minimum.
- GitHubOrg: The GitHub org you are using for this getting-started.
- GitHubUser: Your GitHub username.
- GitHubRepo: The repo we will be using for this example.
Now lets run our updated webhook task.
kubectl apply -f docs/getting-started/webhook-run.yaml
- Commit and push an empty commit to your development repo.
git commit -a -m "build commit" --allow-empty && git push origin mybranch
- Now, you can follow the Task output in
kubectl logs
.- First the image builder task.
kubectl logs -l somelabel=somekey --all-containers
- Then our deployer task.
kubectl logs -l tekton.dev/pipeline=getting-started-pipeline -n getting-started --all-containers
- First the image builder task.
- We can see now that our CI system is working! Images pushed to this repo result in a running pod in our cluster.
- We can examine our pod like so.
- kubectl logs tekton-triggers-built-me -n getting-started --all-containers
- We can examine our pod like so.
Now we can see our new image running our cluster, after having been retrieved, tested, vetted and built, docker pushed (and pulled) and finally ran on our cluster as a Pod.
- Delete the getting-started namespace!
kubectl delete namespace getting-started