Setup Jenkins server

$ mkdir jenkins
$ cd jenkins
$ vim Vagrantfile

Vagrant.configure("2") do |config|
  config.vm.box = "bento/ubuntu-20.04"
  config.vm.network "forwarded_port", guest: 8080, host: 8081, host_ip: "127.0.0.1"
  config.vm.network "private_network", ip: "192.168.10.31"

  config.vm.provision "shell", inline: <<-SHELL
    sudo apt-get update
    sudo apt-get -y upgrade
    sudo apt install openjdk-11-jdk -y  
    wget -q -O - https://pkg.jenkins.io/debian-stable/jenkins.io.key | sudo apt-key add -
    echo "deb https://pkg.jenkins.io/debian-stable binary/" | sudo tee -a  /etc/apt/sources.list > /dev/null
    sudo apt-get update
    sudo apt-get install -y jenkins
  SHELL
end

$ vagrant up
$ vagrabt ssh

Setup Repository for docker

$ sudo apt-get update \
$ sudo apt-get install \
    apt-transport-https \
    ca-certificates \
    curl \
    gnupg-agent \
    software-properties-common


$ curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
$ sudo apt-key fingerprint 0EBFCD88

$ sudo add-apt-repository \
   "deb [arch=amd64] https://download.docker.com/linux/ubuntu \
   $(lsb_release -cs) \
   stable"

Install docker engine

$ sudo apt-get update
$ sudo apt-get install docker-ce docker-ce-cli containerd.io

updated user jenkins to run docker

$ sudo usermod -G docker jenkins	
$ sudo apt-get install acl

$ sudo setfacl -m user:jenkins:rw /var/run/docker.sock

Setup Kubernetes

$ curl -LO https://storage.googleapis.com/kubernetes-release/release/`curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt`/bin/linux/amd64/kubectl

$ chmod +x ./kubectl
$ sudo mv ./kubectl /usr/local/bin/kubectl

$ cp -r ~/.kube /var/lib/jenkins/
$ sudo chown -R jenkins:jenkins /var/lib/jenkins/
$ vim /var/lib/jenkins/.kube/config

		apiVersion: v1
		clusters:
		- cluster:
		    certificate-authority: /var/lib/jenkins/.minikube/ca.crt
		    server: https://192.168.99.100:8443
		  name: minikube
		contexts:
		- context:
		    cluster: minikube
		    user: minikube
		  name: minikube
		current-context: minikube
		kind: Config
		preferences: {}
		users:
		- name: minikube
		  user:
		    client-certificate: /var/lib/jenkins/.minikube/profiles/minikube/client.crt
		    client-key: /var/lib/jenkins/.minikube/profiles/minikube/client.key


❖ make sure the permission of the following files should be as follows
	➢ client.crt 644, 
	➢ client.key 600, 
	➢ ca.crt 644


$ Adding docker hub credentials in jenkins
Credentials → System → Global Credentials → Add Credentials

Job → Pipeline → Poll SCM(after every push it will auto build the job)

❖ Add the groovy script
	➢ either via copy
	➢ or via SCM
❖ Apply → Save → Build
❖ Test on command line
	➢ kubectl get svc
	➢ https://192.168.10.30:<< port >>/hello/deepak

The groovy script:

pipeline {
   agent any
   environment {
       dockerHub = "docker.io"
       docker_cred = 'dockerhub'
   }
   stages {
		stage('SCM Checkout'){
			steps{
				checkout([$class: 'GitSCM',branches: [[name: 'origin/master']],extensions: [[$class: 'WipeWorkspace']],userRemoteConfigs: [[url: 'https://github.com/agrawalpoonam/python-app.git']]  ])
			}
		}
		stage("Build Docker Image"){
			steps{
				sh 'pwd'
				sh "docker build -t poonamag/test-app . --no-cache"
			}
		}
		stage('Upload Image to DockerHub'){
			steps{ 
	     	    withCredentials([
     		 	[$class: 'UsernamePasswordMultiBinding', credentialsId: docker_cred, usernameVariable: 'dockeruser', passwordVariable: 'dockerpass'],
  				]){
					sh "docker login -u ${dockeruser} -p ${dockerpass} ${dockerHub}"
  				}
	    	  	sh 'docker push poonamag/test-app'
	    	 }
	  	}
		stage("Running Docker Image"){
			steps{
				sh "kubectl get namespaces"
				sh "kubectl apply -f deployment.yaml"
			}
		}
}
}