02.01: A Very Simple Tekton Task

A Tekton Task is a collection of steps that run in a specific order. In this example, we’re going to create a Task that echoes “Hello Detroit” to the logs.

Step 1: Create the Task definition

The first thing we need to do is to define the Task. Tasks are defined using YAML. Here is a working Task definition:

apiVersion: tekton.dev/v1beta1
kind: Task
  name: echo-hello-detroit
    - name: echo
      image: ubuntu
      script: |
        echo "Hello Detroit"

In this Task definition:

  • apiVersion: tekton.dev/v1beta1 specifies the Tekton Pipelines API version.
  • kind: Task indicates that this is a Tekton Task.
  • metadata: name: echo-hello-detroit sets the name of the Task.
  • spec
    • steps: contains a list of steps that will be executed in order.
      • name: echo names the step.
      • image: ubuntu specifies the container image to use for the step. In this case, we’re using an Ubuntu image because it has the bash shell and echo command.
      • script: | indicates the start of the script to be run in the container.

Step 2: Apply the Task to your cluster

To apply the Task to your cluster, save the YAML to a file named echo-hello-detroit.yaml, then run:

kubectl apply -f echo-hello-detroit.yaml

This command applies (creates or updates) the Task on your Kubernetes cluster.

Step 3: Check if the Task is created

To check if the Task is created:

kubectl get tasks

If the Task was created successfully, you should see echo-hello-detroit in the list of tasks.

Step 4: Run the Task

To run the Task, you’ll need to create and apply a TaskRun:

apiVersion: tekton.dev/v1beta1
kind: TaskRun
  name: echo-hello-detroit-run
    name: echo-hello-detroit

Save this to a file named echo-hello-detroit-run.yaml, then apply it with kubectl:

kubectl apply -f echo-hello-detroit-run.yaml

Step 5: Check the TaskRun’s log

To check the logs of the TaskRun:

tkn taskrun logs echo-hello-detroit-run -f
# if you don't see any results try
tkn taskrun logs --all echo-hello-detroit-run

You should see the output “Hello Detroit” in the logs. If you need to use--all it just may have taken a bit longer to run.

For more information about Tasks and TaskRuns, follow the links to official Tekton documentation.