Jenkins 流水线语法 02 片段生成器和声明式语法生成器

Pipeline 开发工具

选择任意pipeline类型的作业，点击“流水线语法”即可进入pipeline开发工具页面。

片段生成器

有些pipeline代码不是自己去写的，是要工具帮我们生成的，只需要知道怎么生成就行了

Jenkins会安装很多插件，有些插件会为你提供一些方法，也就是代码化的方法让你去使用片段生成器（下面就是安装好的插件为我们提供的所有功能）

流水线代码片段生成器， 非常好用。在这里可以找到每个插件以及Jenkins内置的方法的使用方法。使用片段生成器可以根据个人需要生成方法，有些方法来源于插件，则需要先安装相关的插件才能使用哦。

使用checkout生成器下载gitlab代码 

checkout([$class: 'GitSCM', branches: [[name: '*/master']], extensions: [], userRemoteConfigs: [[credentialsId: 'dc735f39-1cef-4a12-a499-6c873b82adcc', url: 'http://192.168.179.100/devops/demo-hello-service.git']]])

pipeline {
    agent any

    stages {
        stage('getCode') {
            steps {
               checkout([$class: 'GitSCM', branches: [[name: '*/master']], extensions: [], userRemoteConfigs: [[credentialsId: 'dc735f39-1cef-4a12-a499-6c873b82adcc', url: 'http://192.168.179.100/devops/demo-hello-service.git']]])
            }
        }
    }
}


Started by user admin
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] node
Running on build-01 in /data/cicd/jenkinsagent/workspace/pipeline-test
[Pipeline] {
[Pipeline] stage
[Pipeline] { (getCode)
[Pipeline] checkout
The recommended git tool is: NONE
using credential dc735f39-1cef-4a12-a499-6c873b82adcc
Cloning the remote Git repository
Avoid second fetch
Checking out Revision dc647d4ef52aadabf75db582393156decc4ca6a3 (refs/remotes/origin/master)
Commit message: "Update version"
First time build. Skipping changelog.
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
Cloning repository http://192.168.179.100/devops/demo-hello-service.git
 > git init /data/cicd/jenkinsagent/workspace/pipeline-test # timeout=10
Fetching upstream changes from http://192.168.179.100/devops/demo-hello-service.git
 > git --version # timeout=10
 > git --version # 'git version 2.7.4'
using GIT_ASKPASS to set credentials git-lab-admin-user
 > git fetch --tags --progress http://192.168.179.100/devops/demo-hello-service.git +refs/heads/*:refs/remotes/origin/* # timeout=10
 > git config remote.origin.url http://192.168.179.100/devops/demo-hello-service.git # timeout=10
 > git config --add remote.origin.fetch +refs/heads/*:refs/remotes/origin/* # timeout=10
 > git rev-parse refs/remotes/origin/master^{commit} # timeout=10
 > git config core.sparsecheckout # timeout=10
 > git checkout -f dc647d4ef52aadabf75db582393156decc4ca6a3 # timeout=10
Finished: SUCCESS

使用sh生成器生成shell脚本

pipeline {
    agent any

    stages {
        stage('getCode') {
            steps {
                  sh 'pwd'
            }
        }
    }
}



Started by user admin
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] node
Running on Jenkins in /var/jenkins_home/workspace/pipeline-test
[Pipeline] {
[Pipeline] stage
[Pipeline] { (getCode)
[Pipeline] sh
+ pwd
/var/jenkins_home/workspace/pipeline-test
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
Finished: SUCCESS

声明式语法生成器

脚本方式和声明方式不同的地方： 

如果使用脚本方式的语法和声明式差不多也是node{ stages{......} }，但是用不到一些特性比如post标签，即构建后的操作，因为不支持脚本方式，说白了，脚本方式都得自己去写代码。

如果是脚本方式的，需要自己去写代码去判断流水线的状态，然后去做什么动作，声明方式是官方非常推荐的做法，更加结构化，更加简单，有些功能就已经帮我们实现好了。直接在里面写就行了，就不需要为了一些功能写额外的代码了。

可以在声明方式的里面嵌入脚本方式的代码，默认情况下是不支持的，怎么才可以支持，添加script，这样就可以写脚本，更加灵活

可以生成声明式流水线语法的语句块。

pipeline {
    agent any

    stages {
        stage('getCode') {
            steps {
              script{
           sh '''
           date 
           pwd
           echo "hh"
           '''
                  
              }
            }
        }
    }
}

Started by user admin
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] node
Running on Jenkins in /var/jenkins_home/workspace/pipeline-test
[Pipeline] {
[Pipeline] stage
[Pipeline] { (getCode)
[Pipeline] script
[Pipeline] {
[Pipeline] sh
+ date
Tue May 18 11:36:36 UTC 2021
+ pwd
/var/jenkins_home/workspace/pipeline-test
+ echo hh
hh
[Pipeline] }
[Pipeline] // script
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
Finished: SUCCESS

stages {
  stage('build') {
    steps {
      // One or more steps need to be included within the steps block.
    }
  }

}