前言

参考此教程时，需要提前准备好或了解以下内容：

1. 准备好k8s集群，请参考《使用kubeadm搭建(kubernetes)k8s集群》
2. 准备好harbor仓库，请参考《Harbor 安装》
3. 了解maven构建相关知识，请参考《Maven新手入门》
4. 了解docker镜像构建相关知识，请参考《Dockerfile构建springboot Image》
5. 了解k8s如何部署应用,请参考《在k8s上部署Springboot》
6. 了解jenkins pipeline的基本语法《Jenkins高级篇之Pipeline代码自动化》

环境配置

在Jenkins的服务器上安装好jdk

在Jenkins的服务器上安装好maven

在Jenkins的服务器上安装好docker

Global Tool Configuration（全局工具配置）

1. 找到并打开Jenkins/Global Tool Configuration
   
2. 找到jdk和maven，点击Add JDK 和点击 Add Maven,并根据实际安装情况填入信息
   
   

配置pod template（kubectl）

如果还没有集成kubernetes的，请参考《Jenkins 集成k8s 运行Jenkins slave（Jenkins 弹性slave）》里面的在Jenkins上集成Kubernetes

1. 找到Jenkins/configuration,再找到里面的Cloud，点击Add Pod Template并填入以下信息：
   
   注意：点击 Advance（高级），配置Service Account，根据自己实际配置的Service Account填入，最后Save
   

Jenkins 创建Pipeline

在Jenkins里面创建Pipeline job

1. 点击New Item
   
2. 输入item name: ，并点击Pipeline,最后点OK
   
3. 在Pipeline里面选择Pipeline script，并在Script里面写入pipeline script，script参考下面的编写Pipeline Script部分，点击保存
   

编写Pipeline Script

以下是我准备好的声明式Pipeline，可以直接复制到上面的Pipeline job，点击保存

pipeline {
  agent any
  tools {
      maven 'maven'
      jdk 'jdk'
  }
  stages {
  stage('Init') {
		steps{
			script{
			    deleteDir()
				println "welcome to Nick learn"
				sh 'mkdir workplace'
				
			}
		}
	}
	stage('git source') {
	    steps{
	        script{
	           dir("${env.WORKSPACE}/workplace"){  
                	    git branch: 'env/dev', credentialsId: '11111',url: 'git@192.168.108.132:root/jenkins_slave_k8s.git'
                	}
	        }
	    }
	}
    stage('maven package') {
    		steps{
    			script{
					dir("${env.WORKSPACE}/workplace"){ 
					sh 'mvn clean package'
				}
    		}
    	}	
    }
	
	stage('docker build') {
    		steps{
    			script{
					dir("${env.WORKSPACE}/workplace"){ 
					sh 'docker login -u ' + HARBOR_CREDS_USR  + ' -p ' + HARBOR_CREDS_PSW + ' ' + HARBOR_HOST
					sh "docker build  -t " + HARBOR_HOST + "/" + DOCKER_IMAGE + ":" + GIT_TAG + " --no-cache ."
					sh "docker push " + HARBOR_HOST + "/" + DOCKER_IMAGE + ":" + GIT_TAG
					sh "docker rmi " + HARBOR_HOST + "/" + DOCKER_IMAGE + ":" + GIT_TAG
					
					
					stash(includes: '*.tpl', name: 'workplace')
					
				}
    		}
    	}	
    }
	
	  stage('K8s Deploy') {
    agent {
    node {
      label 'k8s_deploy'
    }

  }
      steps {
        script {

          container('kubectl') {
			unstash 'workplace'
		    sh 'ls'
            sh "sed -e 's#{IMAGE_URL}#" + HARBOR_HOST + "/" + DOCKER_IMAGE + "#g;s#{IMAGE_TAG}#" + GIT_TAG + "#g;s#{APP_NAME}#" + APP_NAME + "#g;s#{SPRING_PROFILE}#k8s-test#g' k8s-deployment.tpl > k8s-deployment.yml"
			sh "sed -e 's#{APP_NAME}#" + APP_NAME + "#g;s#{NODE_PORT}#" + NODE_PORT + "#g' k8s-deployment-svc.tpl > k8s-deployment-svc.yml"
            try{
                sh "kubectl delete rc " + APP_NAME + " --namespace=" + K8S_NAMESPACE
				
            }catch (Exception e) {
				println e
			}
			
			 try{
                sh "kubectl delete svc " + APP_NAME + " --namespace=" + K8S_NAMESPACE
				
            }catch (Exception e) {
				println e
			}
			
			

            
            sh "kubectl apply -f k8s-deployment.yml --namespace=" + K8S_NAMESPACE
			sh "kubectl apply -f k8s-deployment-svc.yml --namespace=" + K8S_NAMESPACE
          }
        }

      }
    }

  }

   environment {
        HARBOR_CREDS = credentials('jenkins-harbor-creds')
		GIT_TAG = sh(returnStdout: true,script: 'echo ' + BUILD_NUMBER ).trim()
    }
  parameters {
    string(name: 'HARBOR_HOST', defaultValue: '192.168.108.131', description: 'harbor仓库地址')
    string(name: 'DOCKER_IMAGE', defaultValue: 'practice/jenkins_demo_practice', description: 'docker镜像名')
    string(name: 'APP_NAME', defaultValue: 'jenkinsDemoPractice', description: 'k8s中标签名')
	string(name: 'NODE_PORT', defaultValue: '30000', description: 'Service端口')
    string(name: 'K8S_NAMESPACE', defaultValue: 'devops', description: 'k8s的namespace名称')
  }

}