Tektoncd development

Diving into the cat’s project 🐱

Let’s dig into how I setup my development environment when working on tektoncd/pipeline

What is Tektoncd ?

tekton-horizontal-color.png

The Tekton Pipelines project provides Kubernetes-style resources for declaring CI/CD-style pipelines.

  • Started as an experiment from Knative to define more advance build use cases that knative/build was able to.
  • Is now it’s own project and GitHub organization.

Basic development environment setup

Requirements

  • go : installation depends on your operating system
  • ko : go get -u github.com/google/go-containerregistry/cmd/ko
  • kubernetes
    • minikube
    • minishift

Minikube

$ minikube profile tektoncd
$ minikube config set kubernetes-version "v1.13.2"
$ minikube config set memory "8192"
$ minikube config set cpus "4"
# linux-only with libvirt, qemu-kvm
$ minikube config set vm-driver "kvm2"
$ minikube start
✅  minikube profile was successfully set to tektoncd
⚠️  These changes will take effect upon a minikube delete and then a minikube start
⚠️  These changes will take effect upon a minikube delete and then a minikube start
⚠️  These changes will take effect upon a minikube delete and then a minikube start
😄  minikube v0.35.0 on linux (amd64)
🔥  Creating kvm2 VM (CPUs=4, Memory=8192MB, Disk=20000MB) ...
📶  "tektoncd" IP address is 192.168.39.241
🐳  Configuring Docker as the container runtime ...
✨  Preparing Kubernetes environment ...
🚜  Pulling images required by Kubernetes v1.13.2 ...
🚀  Launching Kubernetes v1.13.2 using kubeadm ...
⌛  Waiting for pods: apiserver proxy etcd scheduler controller addon-manager dns
🔑  Configuring cluster permissions ...
🤔  Verifying component health .....
💗  kubectl is now configured to use "tektoncd"
🏄  Done! Thank you for using minikube!

Minishift

$ minishift profile set tektoncd
$ minishift config set openshift-version "v3.11.0"
$ minishift config set memory "8192"
$ minishift config set cpus "4"
$ minishift config set image-caching "true"
$ minishift addons enable admin-user
$ minishift addons enable anyuid
$ minishift start
-- Starting profile 'tektoncd'
-- Check if deprecated options are used ... OK
-- Checking if https://github.com is reachable ... OK
-- Checking if requested OpenShift version 'v3.11.0' is valid ... OK
-- Checking if requested OpenShift version 'v3.11.0' is supported ... OK
-- Checking if requested hypervisor 'kvm' is supported on this platform ... OK
-- Checking if KVM driver is installed ...
# […]
-- Starting the OpenShift cluster using 'kvm' hypervisor ...
-- Minishift VM will be configured with ...
   Memory:    8 GB
   vCPUs :    4
   Disk size: 20 GB
# […]
   -- Starting OpenShift cluster ...........

Creating initial project "myproject" ...
Server Information ...
OpenShift server started.

The server is accessible via web console at:
    https://192.168.42.95:8443/console

You are logged in as:
    User:     developer
    Password: <any value>

To login as administrator:
    oc login -u system:admin


-- Applying addon 'admin-user':..
-- Applying addon 'anyuid':.
# […]

Environments

We need to configure ko (using KO_DOCKER_REPO) so that it can deploy the working copy code into our development cluster.

  • minikube (or minishift) with docker as container runtime
    1. Make sure your local docker command-line points to the VM daemon

      eval $(minikube docker-env)
      # eval $(minishift docker-env) # for minishift
      
    2. Use ko.local as KO_DOCKER_REPO — it’s a special case handled by ko

      export KO_DOCKER_REPO=ko.local
      
  • for any cluster using another runtime (or a remote cluster), you need to use a registry that will be accessible from the cluster (gcr.io or your own – the docker hub doesn’t work with ko).

Deploy tektoncd/pipeline

  1. tektoncd/pipeline needs to sit on the right place in your GOPATH

    $ echo $GOPATH
    /home/vincent
    $ pwd
    /home/vincent/src/github.com/tektoncd/pipeline
    
  2. Deploy 💃

    $ ko apply -f ./config
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/webhook
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/gsutil
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/controller
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/nop
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/creds-init
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/git-init
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/kubeconfigwriter
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/bash
    2019/03/13 10:49:22 Building github.com/tektoncd/pipeline/cmd/entrypoint
    namespace/tekton-pipelines created
    clusterrole.rbac.authorization.k8s.io/tekton-pipelines-admin created
    serviceaccount/tekton-pipelines-controller created
    clusterrolebinding.rbac.authorization.k8s.io/tekton-pipelines-controller-admin created
    2019/03/13 10:49:23 Using base index.docker.io/library/busybox:latest for github.com/tektoncd/pipeline/cmd/entrypoint
    2019/03/13 10:49:23 Using base gcr.io/distroless/static:latest for github.com/tektoncd/pipeline/cmd/nop
    # […]
    deployment.apps/tekton-pipelines-controller created
    deployment.apps/tekton-pipelines-webhook created
    
  3. Enjoy 🔥

    $ kubectl get all -n tekton-pipelines
    NAME                                               READY     STATUS    RESTARTS   AGE
    pod/tekton-pipelines-controller-5875857cf5-k9njx   1/1       Running   0          3m18s
    pod/tekton-pipelines-webhook-54785c88f4-jbkqr      1/1       Running   0          3m18s
    
    NAME                                  TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
    service/tekton-pipelines-controller   ClusterIP   10.104.145.40   <none>        9090/TCP   4m31s
    service/tekton-pipelines-webhook      ClusterIP   10.97.9.56      <none>        443/TCP    4m31s
    
    NAME                                          READY     UP-TO-DATE   AVAILABLE   AGE
    deployment.apps/tekton-pipelines-controller   1/1       1            1           3m18s
    deployment.apps/tekton-pipelines-webhook      1/1       1            1           3m18s
    
    NAME                                                     DESIRED   CURRENT   READY     AGE
    replicaset.apps/tekton-pipelines-controller-5875857cf5   1         1         1         3m18s
    replicaset.apps/tekton-pipelines-webhook-54785c88f4      1         1         1         3m18s
    

An example

Let’s validate it works by running a simple example

apiVersion: tekton.dev/v1alpha1
kind: Task
metadata:
  name: build-simple
spec:
  steps:
  - name: build-simple
    image: docker.io/library/busybox
    command:
    - /bin/sh
    args:
    - -c
    - "echo hello world"
---
apiVersion: tekton.dev/v1alpha1
kind: TaskRun
metadata:
  name: build-simple
spec:
  taskRef:
    name: build-simple
  trigger:
    type: manual
$ kubectl apply -f ./test.yaml
task.tekton.dev/build-simple created
taskrun.tekton.dev/build-simple created

Let’s now look at what’s in our namespace

$ kubectl get all
NAME                          READY     STATUS      RESTARTS   AGE
pod/build-simple-pod-ada879   0/2       Completed   0          10s

NAME                 TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
service/kubernetes   ClusterIP   10.96.0.1    <none>        443/TCP   26m

NAME                           AGE
task.tekton.dev/build-simple   10s

NAME                              AGE
taskrun.tekton.dev/build-simple   10s

Development workflow

When you’re working on pipeline, usually you want :

  1. make sure it compiles : go build -v ./..
  2. Running unit tests : go test ./... (bonus use ram for continuous testing)
  3. End-to-end tests : go test -tags e2e ./... (or simply using `./test/` package)

    Make sure you re-deploy before running the e2e tests using ko apply -f ./config, otherwise you’re testing the wrong code.

Code walkthrough

Let’s look into tektoncd/pipeline sources

  • Go packages
    • cmd
    • pkg
      • apis : api types
      • client : generated client
      • reconcilier : core of the pipeline controller
  • Tests
  • CI related files