ref(12): Jenkins on Docker and CasC configuration

test/jenkins/README.md

@@ -1,12 +1,70 @@
-# Automate Jenkins Installation on Docker for Testing
+# Automated Jenkins Installation on Docker for Testing with Kubernetes Integration
+
+## Prerequisites
+
+- Docker must be installed.
+- Kubernetes must be installed.
+
+## Installation
+
+To set up a new Jenkins instance, execute the following command:
+```bash
+./test/jenkins/install.sh
+```
+
+## Testing
+
+Follow these steps to test the Kubernetes integration:
+
+1. Create a pipeline named `test-kubernetes-agent`.
+2. Insert the provided pipeline definition script:
+
+```groovy
+pipeline {
+    agent {
+        kubernetes {
+            yaml '''
+        apiVersion: v1
+        kind: Pod
+        spec:
+          containers:
+          - name: maven
+            image: maven:alpine
+            command:
+            - cat
+            tty: true
+          - name: node
+            image: node:16-alpine3.12
+            command:
+            - cat
+            tty: true
+        '''
+        }
+    }
+    stages {
+        stage('Run maven') {
+            steps {
+                container('maven') {
+                    sh 'mvn -version'
+                }
+                container('node') {
+                    sh 'npm version'
+                }
+            }
+        }
+    }
+}
+```
+
+3. Execute the pipeline; two agents should be deployed on the Kubernetes cluster.
 
 ## References
 
-- https://www.digitalocean.com/community/tutorials/how-to-automate-jenkins-setup-with-docker-and-jenkins-configuration-as-code
-- https://github.com/abrahamNtd/poc-jenkins-jcasc
-- https://github.com/jenkinsci/configuration-as-code-plugin/tree/master/demos
-- https://www.youtube.com/watch?v=ZXaorni-icg
+- [Automating Jenkins Setup with Docker and Jenkins Configuration as Code](https://www.digitalocean.com/community/tutorials/how-to-automate-jenkins-setup-with-docker-and-jenkins-configuration-as-code)
+- [GitHub - Jenkins Configuration as Code Plugin Demos](https://github.com/jenkinsci/configuration-as-code-plugin/tree/master/demos)
+- [YouTube - Automated Jenkins Setup using Docker and Configuration as Code](https://www.youtube.com/watch?v=ZXaorni-icg)
+- [GitHub Gist - Kubernetes Cluster Info Command](https://gist.github.com/darinpope/67c297b3ccc04c17991b22e1422df45a)
 
-## Commands
+## Useful Commands
 
-- `kubectl cluster-info`: get infos on kubernetes cluster almost the Kubernetes control plane address: https://kubernetes.docker.internal:6443
+- `kubectl cluster-info`: Retrieve information about the Kubernetes cluster, including the Kubernetes control plane address (e.g., https://kubernetes.docker.internal:6443).

test/jenkins/install.sh

@@ -6,14 +6,15 @@ set -euo pipefail
 install::_configure_kubernetes() {
   declare -r name="jenkins"
 
-  kubectl delete namespace "${name}"
+  kubectl delete namespace "${name}" || true
 
   kubectl create namespace "${name}"
   kubectl create serviceaccount "${name}" --namespace="${name}"
   kubectl create token "${name}" --namespace="${name}"
   kubectl create rolebinding "${name}"-admin-binding --clusterrole=admin --serviceaccount="${name}":"${name}" --namespace="${name}"
 
-  local TOKEN=$(kubectl create token "${name}" --namespace="${name}")
+  local TOKEN
+  TOKEN=$(kubectl create token "${name}" --namespace="${name}")
   sed "s/<SERVICE_ACCOUNT_TOKEN>/${TOKEN}/g" "${JENKINS_INSTALLATION_CONFIG}/secrets-template.properties" > "${JENKINS_INSTALLATION_CONFIG}/secrets.properties"
 }