csantanapr/tutorial-tekton-argocd-pipeline

Tutorial for Tekton and ArgoCD Integration

This tutorial shows the concept of seperation of concerns in DevOps. The project is setup in 3 repos (not all teams will have write access to all of them)

• This git repo only contains the pipeline setup

  • https://github.com/csantanapr/tutorial-tekton-argocd-pipeline

• The git repo that contains only the application source code

  • https://github.com/csantanapr/tutorial-tekton-argocd-code

• The git repo that contains only the infrastructure manifests (yaml)

  • https://github.com/csantanapr/tutorial-tekton-argocd-infra

• We will be using Tekton to build the container image, and update the Infra Git repo.

• We will be using ArgoCD to deploy the application from the infra git repo

Setup Git repositories

• Get a copy of the devops git repository and change directory

  git clone https://github.com/csantanapr/tutorial-tekton-argocd-pipeline
  cd tutorial-tekton-argocd-pipeline

• Create a new code git repository using this repo as template
• Create a new infra git repository using this repo as template

Setup Cluster

• You need an OpenShift 4 cluster, you can use CodeReadyContainers (CRC), OpenShift PlayGround, or OpenShift from a cloud provider like IBM Cloud
• Install OpenShift Operators
  • Install OpenShift Pipeline Operator

    oc apply -f operators/tekton-operator.yaml

  • Install ArgoCD (HELM) Operator on the argocd namespace

    oc apply -f operators/argocd-operator.yaml

    When installing the tutorial, make sure you wait until the argocd-operator is finished before installing the argocd-cr..or it will fail. You can do this:

    oc get ClusterServiceVersion -n argocd
    NAME                                   DISPLAY                        VERSION   REPLACES   PHASE
    argocd-operator.v0.0.8                 Argo CD                        0.0.8                Succeeded

    and wait for the "succeeded" to come up before proceeding.

    oc apply -f operators/argocd-cr.yaml

    and waut for the argocd server Pod to be running

    oc get pods -n argocd -l app.kubernetes.io/name=example-argocd-server
    

    NAME                                     READY   STATUS    RESTARTS   AGE
    example-argocd-server-57c4fd5c45-zf4q6   1/1     Running   0          115s
    

Setup CLIs

• Install Tekton CLI tkn
• Install ArgoCD CLI argocd

Setup target Namespace

• Create a new namespace/project

  oc new-project tekton-argocd

• Set the environment variable NAMESPACE

  export NAMESPACE=$(oc project -q)
  echo "NAMESPACE set to $NAMESPACE"

Create ArgoCD Application

• Set an environment variable ARGOCD_URL using the route

  export ARGOCD_NAMESPACE="argocd"
  export ARGOCD_SERVER=$(oc get route example-argocd-server -n $ARGOCD_NAMESPACE -o jsonpath='{.spec.host}')
  export ARGOCD_URL="https://$ARGOCD_SERVER"
  echo ARGOCD_URL=$ARGOCD_URL
  echo ARGOCD_SERVER=$ARGOCD_SERVER

• Login into the UI.

  open $ARGOCD_URL

• Use admin as the username and get the password with the following command

  oc get secret example-argocd-cluster -n $ARGOCD_NAMESPACE -o jsonpath='{.data.admin\.password}' | base64 -d

  For example the output is similar to this:

  tyafMb7BNvO0kP9eizx3CojrK8pYJFQq
  

  export ARGOCD_PASSWORD=$(oc get secret example-argocd-cluster -n $ARGOCD_NAMESPACE -o jsonpath='{.data.admin\.password}' | base64 -d)

• Login into ArgoCD

  argocd login --username admin --password $ARGOCD_PASSWORD $ARGOCD_SERVER

  Note: if you have problems with DNS using CRC, you might need to edit /etc/hosts and add entry for the $ARGOCD_SERVER with IP Address from crc ip

• Create the App in ArgoCD using your own Infra git repository

  export GIT_REPOSITORY_URL="https://github.com/csantanapr/tutorial-tekton-argocd-infra"

  export ARGOCD_APP=$(oc project -q)
  export GIT_MANIFEST_DIR="yamls/ocp"

  argocd app create $ARGOCD_APP \
  --project default \
  --repo $GIT_REPOSITORY_URL \
  --path $GIT_MANIFEST_DIR \
  --dest-server https://kubernetes.default.svc \
  --dest-namespace $NAMESPACE \
  --sync-policy automated \
  --self-heal \
  --auto-prune

  application 'tekton-argocd' created
  

Build Image with Tekton

• Deploy the pipeline assets, edit the pipelines/git.yaml and pipelines/pipeline-build-git.yaml and use your own Code and Infra git repositories respectively.

  oc apply -f pipeline/ -n $NAMESPACE

  tkn resources ls -n $NAMESPACE

  NAME     TYPE    DETAILS
  source   git     url: https://github.com/csantanapr/tutorial-tekton-argocd-code
  image    image   url: image-registry.openshift-image-registry.svc:5000/$NAMESPACE/app
  

  tkn task ls -n $NAMESPACE

  NAME        AGE
  build       36 seconds ago
  build-git   36 seconds ago
  

  tkn pipeline ls -n $NAMESPACE

  NAME        AGE              LAST RUN   STARTED   DURATION   STATUS
  build-git   17 seconds ago   ---        ---       ---        ---
  

• Run the build task to test image build only

  tkn task start build \
    -i image=image \
    -i source=source \
    --showlog \
    -s pipeline \
    -n $NAMESPACE

  tkn taskrun ls -n $NAMESPACE

  NAME              STARTED         DURATION    STATUS
  build-run-c4d4r   4 minutes ago   2 minutes   Succeeded
  

  oc get imagestream -n $NAMESPACE

  NAME   IMAGE REPOSITORY                                                     TAGS      UPDATED
  app    image-registry.openshift-image-registry.svc:5000/tekton-argocd/app   b711ac7   About a minute ago
  

Update Infrastructure Git repo

Configure Github Personal Access Token

• For your CI pipeline to connect to and use your GitHub repo, it will need a GitHub personal access token with public_repo and write:repo_hook scopes.

• Navigate to Developer Settings and generate a new token; name it something like "CI pipeline"

• Select public_repo scope to enable git clone

• Select write:repo_hook scope so the pipeline can create a web hook

• The GitHub UI will never again let you see this token, so be sure to save the token in your password manager or somewhere safe that you can access later on

• Create the secret for the Infra repository, replace <GIT_USERNAME> and <GIT_TOKEN>, keep the quotes

  export GIT_USERNAME='<GIT_USERNAME>'
  export GIT_TOKEN='<GIT_TOKEN>'

  oc create secret generic git-infra-secret \
    --from-literal=username="$GIT_USERNAME" \
    --from-literal=token="$GIT_TOKEN" \
    -n $NAMESPACE

• Run Pipeline to Build Image and Update Infra Git repo

  tkn pipeline start build-git \
              --showlog \
              -r source=source \
              -r image=image \
              -s pipeline \
              -n $NAMESPACE

  tkn pipeline ls -n $NAMESPACE

  NAME        AGE             LAST RUN              STARTED         DURATION   STATUS
  build-git   2 minutes ago   build-git-run-rdhmj   2 minutes ago   1 minute   Succeeded
  

Extra Credit: Create Git Webhook

• This is only possible if your OpenShift cluster is accessible from the the github server (ie github.com)

• Create a WebHook for the Code Git repo

  oc apply -f triggers/ -n $NAMESPACE

  oc create route edge --service=el-cicd -n $NAMESPACE

  export GIT_WEBHOOK_URL=$(oc get route el-cicd -o jsonpath='{.spec.host}' -n $NAMESPACE)
  echo "https://$GIT_WEBHOOK_URL"

• Set the GIT_REPO_NAME to name of the Code Git repo like tutorial-tekton-argocd-code

  export GIT_REPO_NAME='<GIT_REPO_NAME>'

• Set the GIT_REPO_OWNER to name of the Code Git repo like csantanapr

  export GIT_REPO_OWNER='<GIT_REPO_OWNER>'

• Run curl to create the web hook

  curl -v -X POST -u $GIT_USERNAME:$GIT_TOKEN \
  -d "{\"name\": \"web\",\"active\": true,\"events\": [\"push\"],\"config\": {\"url\": \"https://$GIT_WEBHOOK_URL\",\"content_type\": \"json\",\"insecure_ssl\": \"0\"}}" \
  -L https://api.github.com/repos/$GIT_REPO_OWNER/$GIT_REPO_NAME/hooks

Make a change on the Code repository, and verify that Github sent the WebHook to the event listener, and that the Pipeline runs in OpenShift Console