antony@notes:~/ops-automation$ cat "Jenkins.md"

Jenkins

2022-06-13· ops-automation ·CI/CD

Jenkins

[TOC]

環境準備

CNT.2022.v4 K8S 叢集建置完成以下 K8S 公設完成部署

MetalLB
Ingress NGINX Controller
Local Path Provisioner

在 Windows 系統的 cmd 視窗登入 m1 主機修改 /etc/hosts

$ sudo nano /etc/hosts
	::
192.168.124.220 quay.k8s.org jenkins.k8s.org

參考 902 簡報完成 git 必要設定

$ git config --list
user.name=danny
user.email=danny@example.com
core.editor=nano

Jenkins 參考資料

https://www.jenkins.io/

https://github.com/jenkinsci/jenkins
https://www.jenkins.io/doc/book/using/

Jenkins 介紹

Jenkins is a self-contained, open source automation server which can be used to automate all sorts of tasks related to building, testing, and delivering or deploying software.

Jenkins can be installed through native system packages, Docker, or even run standalone by any machine with a Java Runtime Environment (JRE) installed.

Jenkins Plugins

Jenkins Plugins 網站連結

There are over a thousand different plugins which can be installed on a Jenkins controller and to integrate various build tools, cloud providers, analysis tools, and much more.

JCasC

Jenkins Configuration as Code https://plugins.jenkins.io/configuration-as-code/

Jenkins Configuration as Code provides the ability to define this whole configuration as a simple, human-friendly, plain text yaml syntax.

Kubernetes plugin

Kubernetes plugin for Jenkins https://plugins.jenkins.io/kubernetes/

Jenkins plugin to run dynamic agents in a Kubernetes cluster.

The plugin creates a Kubernetes Pod for each agent started, and stops it after each build.

It is not required to run the Jenkins controller inside Kubernetes.

部署前置作業

$ pwd
/home/bigred/wk

$ kubectl create ns jenkins
namespace/jenkins created

## kubeconfig 為 secret 物件的名字
$ kubectl create secret generic kubeconfig --from-file=/home/bigred/.kube/config -n jenkins
secret/kubeconfig created


$ kubectl apply -f http://web.flymks.com/cicd/v1/jenkins.yaml

$ kubectl get all -n jenkins
NAME          READY   STATUS    RESTARTS   AGE
pod/jenkins   1/1     Running   0          89s

NAME              TYPE        CLUSTER-IP    EXTERNAL-IP   PORT(S)            AGE
service/jenkins   ClusterIP   10.98.0.124   <none>        80/TCP,50000/TCP   89s

$ kubectl get ingress -n jenkins
NAME              CLASS   HOSTS             ADDRESS          PORTS   AGE
jenkins-ingress   ig1     jenkins.k8s.org   192.168.61.220   80      109s

登入 Jenkins

打開瀏覽器，網址 http://jenkins.k8s.org

帳號：jenkins
密碼：Jenkins12345

Jenkins 主畫面

執行第一個 Job

左側按下「馬上建置」

檢視執行結果

滑鼠移至綠色區塊可確認 Log 左側下方「建置歷程」點選 #1 選擇 Console Output 查看終端機輸出

進入 Blue Ocean

左側按下「Open Blue Ocean」進入 Blue Ocean 畫面後，點選中間第一列如下圖紅框處

Blue Ocean 介面

離開 Blue Ocean

右上點選 X 先離開執行結果畫面

右上點選回到經典界面的圖示

設定 SSH 免密碼

Jenkins 透過 SSH 連接 Git Jenkins 主機中已預先產生 SSH 公私鑰將公鑰給 M1 主機

$ kubectl -n jenkins exec -it jenkins -- cat /var/jenkins_home/.ssh/ssh_host_rsa_key.pub | tee -a ~/.ssh/authorized_keys

mycicd 專案資料夾

於 m1 主機建立 mycicd 專案資料夾建立一個檔案並完成 git 備份

~/wk$ mkdir mycicd; cd mycicd
$ git init
$ echo "Hi! Jenkins!" > readme
$ git add readme; git commit -m 'Init repo'

新增 Jenkins Job

回到 Jenkins Dashboard 點選左側新增作業 item name 輸入 mycicd 下方選擇 Multibranch Pipeline 按下 OK

點選 Branch Sources 頁籤 🡪 點選 Add source 下拉選 Git Project Repository 輸入(紅字請替換為 m1 主機 IP)

ssh://bigred@192.168.61.4/home/bigred/wk/mycicd

Credentials 選擇 ssh-private-key 最後按下 Save

Jenkins 掃描儲存庫

新增作業完成後 Jenkins 會自動掃描 Git 儲存庫

撰寫 Jenkinsfile

:::success

Jenkinsfile 使用 echo 語法輸出字串

$ nano Jenkinsfile
pipeline {
    agent { label 'master' }
    stages {
        stage ('echo') {
            steps {
                echo "Hello!"
            }
        }
    }
}

steps ，步驟注意！echo "Hello!" 的 echo 不是 linux 的 echo

:::

手動通知 Jenkins

必需先將 Jenkinsfile 備份至 Git 儲存庫

$ git add Jenkinsfile
$ git commit -m "Add Jenkinsfile"

手動通知 Jenkins

$ curl http://jenkins.k8s.org/git/notifyCommit?url=ssh://bigred@192.168.61.4/home/bigred/wk/mycicd
No git jobs found
Scheduled indexing of mycicd

確認執行結果

Jenkins 網頁 Dashboard 點選 mycicd 點選 master 確認 Stage View 並檢視 Logs 至 Blue Ocean 界面確認結果

搭配 Git Hooks

搭配 Git Hooks 達到 commit 後自動通知 Jenkins

使用 post-commit

建立 post-commit
$ cat << EOF > .git/hooks/post-commit
#!/bin/bash

curl -s http://jenkins.k8s.org/git/notifyCommit?url=ssh://bigred@192.168.61.4/home/bigred/wk/mycicd 
EOF

務必賦予執行權限
$ chmod +x .git/hooks/post-commit

修改 Jenkinsfile

:::success

Jenkinsfile 使用 sh 語法執行指令

$ nano Jenkinsfile
pipeline {
    agent { label 'master' }
    stages {
        stage ('shell') {
            steps {
                sh "whoami"
                sh "pwd"
                sh "ls -al"
            }
        }
    }
}

stage 取名為 shell steps 步驟裡面的 sh 代表要執行我們的 shell 程式，可以幫我們執行 linux 的 command

:::

觸發 post-commit

$ git add Jenkinsfile ; git commit -m "Update Jenkinsfile"

Jenkins 網頁 Dashboard 點選 mycicd 點選 master 確認 Stage View 並檢視 Logs 至 Blue Ocean 界面確認結果

Jenkinsfile 練習

:::success

修改 Jenkinsfile Pipeline 有兩個 stage，分別是 echo 與 shell echo stage，使用 echo 語法輸出 Hello! shell stage 依序執行以下命令

cat /etc/os-release
hostname
hostname -i
whoami
pwd
ls -al

答案：

$ nano Jenkinsfile
pipeline {
    agent { label 'master' }
    stages {
        stage ('echo') {
            steps {
                echo "Hello"
            }
        }
        stage ('shell') {
            steps {
                sh "cat /etc/os-release"
                sh "hostname"
                sh "hostname -i"
                sh "whoami"
                sh "pwd"
                sh "ls -al"
            }
        }
    }
}

$ git add Jenkinsfile ; git commit -m "Update Jenkinsfile 2"

:::

dynamic agents

Jenkins 透過 Kubernetes plugin 可以動態產生 Pod Agent 概念等同 Worker Master 與 Agent 透過 JNLP 協定溝通

Jenkinsfile 範例 01

下載 Jenkinsfile 範例 01

$ wget -q -O Jenkinsfile \
"http://web.flymks.com/cicd/v1/jenkinsfile/01"

檢視 Jenkinsfile 範例 01

$ cat Jenkinsfile
pipeline {
    agent {
        kubernetes {
            inheritFrom 'mycicd'
            yaml """
apiVersion: v1
kind: Pod
spec:
  containers:
  - name: jnlp
    image: quay.io/flysangel/inbound-agent:4.13-2-jdk11
"""
        }
    }
    stages {
        stage ('shell') {
            steps {
                sh 'whoami'
                sh 'pwd'
                sh 'ls -al'
                sh 'cat readme'
            }
        }
    }
}

如果不宣告 pod 的 Container 的 image 為 qua.io 來源的話，預設是 ducker.hub 的 image 中心。

確認範例 01 結果

$ git add Jenkinsfile; git commit -m "test 01"

觀察作業用 Pod 是否有產生

$ watch kubectl get pod -n jenkins

請至 Jenkins 網頁確認執行結果 !

Multiple containers

可以透過 Container 的技術達成不同的效果

## 下載 Jenkinsfile 範例 02
$ wget -q -O Jenkinsfile \
"http://web.flymks.com/cicd/v1/jenkinsfile/02"

## 檢視 Jenkinsfile 範例 02
$ cat Jenkinsfile
pipeline {
    agent {
        kubernetes {
            inheritFrom 'mycicd'
            yaml """
apiVersion: v1
kind: Pod
spec:
  containers:
  - name: jnlp
    image: quay.io/flysangel/inbound-agent:4.13-2-jdk11
  - name: p1
    securityContext:
      privileged: true
    image: quay.io/podman/stable:v3.4.7
    command: ["sleep"]
    args: ["infinity"]
"""
        }
    }
    options {
        skipDefaultCheckout true
    }
    stages {
        stage ('podman') {
            steps {
                sh 'podman version || echo "command not found"'
                container('p1') {
                    sh 'podman version'
                }
            }
        }
    }
}

如果要更進階的學習 Jenkins 的 pipeline ，請點連結

以上的語言最後都會翻譯成 Groovy 語言

## 下載 Jenkinsfile 範例 05
$ wget -q -O Jenkinsfile \
"http://web.flymks.com/cicd/v1/jenkinsfile/05"

$ cat Jenkinsfile
pipeline {
    agent {
        kubernetes {
            inheritFrom 'mycicd'
            yaml """
apiVersion: v1
kind: Pod
spec:
  containers:
  - name: jnlp
    image: quay.io/flysangel/inbound-agent:4.13-2-jdk11
  - name: p1
    securityContext:
      privileged: true
    image: quay.io/podman/stable:v3.4.7
    command: ["sleep"]
    args: ["infinity"]
"""
        }
    }
    options {
        skipDefaultCheckout true
    }
    stages {
        stage ('podman login') {
            steps {
                container('p1') {
                    sh 'podman login --tls-verify=false -u=quay -p=Quay12345 quay.k8s.org'
                }
            }
        }
    }
}

stage 階段 steps 步驟

Jenkins 如果沒有特定宣告哪一個 Contianer 的話，預設是 jnlp 那台 Container

結果報錯

$ git add Jenkinsfile
$ git commit -m "test05"
+ podman login --tls-verify=false -u=quay -p=Quay12345 quay.k8s.org

Error: authenticating creds for "quay.k8s.org": pinging container registry quay.k8s.org: Get "http://quay.k8s.org/v2/": dial tcp: lookup quay.k8s.org: no such host

script returned exit code 125

## Jenkinsfile 05-1
$ nano Jenkinsfile
pipeline {
    agent {
        kubernetes {
            yaml """
apiVersion: v1
kind: Pod
spec:
  hostAliases:
  - ip: "192.168.61.220"
    hostnames:
    - "quay.k8s.org"
  containers:
  - name: jnlp
--- 以下省略 ---

## Jenkinsfile 05-2
$ cat Jenkinsfile
pipeline {
    agent {
        kubernetes {
            inheritFrom 'mycicd'
            yaml """
apiVersion: v1
kind: Pod
spec:
  hostAliases:
  - ip: "192.168.61.220"
    hostnames:
    - "quay.k8s.org"
  containers:
  - name: jnlp
    image: quay.io/flysangel/inbound-agent:4.13-2-jdk11
  - name: p1
    securityContext:
      privileged: true
    image: quay.io/podman/stable:v3.4.7
    command: ["sleep"]
    args: ["infinity"]
"""
        }
    }
    options {
        skipDefaultCheckout true
    }
    stages {
        stage ('podman login') {
            steps {
                container('p1') {
                    sh 'podman login --tls-verify=false -u=quay -p=Quay12345 quay.k8s.org'
                }
            }
        }
        stage ('hostAliases') {
            steps {
                sh 'cat /etc/hosts'
                container('p1') {
                    sh 'cat /etc/hosts'
                }
            }
        }
    }
}

tags: `CI/CD`

Git - Part 2 Jenkins - Part 2

Jenkins

Jenkins

環境準備

Jenkins 參考資料

Jenkins 介紹

Jenkins Plugins

JCasC

Kubernetes plugin

部署前置作業

登入 Jenkins

Jenkins 主畫面

執行第一個 Job

檢視執行結果

進入 Blue Ocean

Blue Ocean 介面

離開 Blue Ocean

設定 SSH 免密碼

mycicd 專案資料夾

新增 Jenkins Job

Jenkins 掃描儲存庫

撰寫 Jenkinsfile

手動通知 Jenkins

搭配 Git Hooks

使用 post-commit

修改 Jenkinsfile

觸發 post-commit

Jenkinsfile 練習

dynamic agents

Jenkinsfile 範例 01

確認範例 01 結果

Multiple containers

tags: CI/CD

tags: `CI/CD`