Jenkins基础：Jenkinsfile使用实例：5:使用when进行条件分支处理when{}环境准备获取Jenkins-Crumb创建JobJenkinsfile说明执行Job总结

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我是靠谱客的博主飘逸书本，最近开发中收集的这篇文章主要介绍Jenkins基础：Jenkinsfile使用实例：5:使用when进行条件分支处理when{}环境准备获取Jenkins-Crumb创建JobJenkinsfile说明执行Job总结，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

如何根据指定的条件进行不同的逻辑处理，这是很多场景中需要碰到的情况。将Pipeline封装成很多条不需要考虑逻辑的多条流水线的做法，在分支逻辑稍微复杂的情况下变得完全不具有可操作性，在这篇文章中将会结合使用示例介绍如何在Jenkinsfile进行条件分支的处理。

when{}

根据给定条件决定实际的分支处理逻辑，可以考虑在Jenkinsfile中使用when{}来达到这一目的。在本文中将仅仅介绍最为简单的逻辑分支处理方式，至于嵌套和多层逻辑处理将在后续的文章中进一步地展开。

使用限制：需要写在stage块中
可选vs必选：可选

内建条件类型

when所支持内建条件类型非常丰富，详细如下所示

内建条件类型	使用说明	备注
branch	指定分支构建时触发	仅对于多分支Pipeline有效
buildingTag	构建tag时触发	-
changelog	SCM的变更日志包含指定内容时触发	常与正则表达式结合使用
changeset	SCM的changeset包含指定文件时触发	常与*等表达式结合使用，缺省状态是不区分大小写的，但是可以通过指定caseSensitive为true来达到区分大小写的目的
changeRequest	变更请求发生时触发（比如Github的Pull Request、Gitlab的Merge Request以及Gerrit的变更等）	如未指定参数则标明每次变更请求都会被触发，分支信息/标题/author/邮件地址等都可以作为参数传入，从而限制只有这些信息被匹配的时候才会发生触发。同时还可以与正则表达式结合使用。
environment	当某环境变量被设定为某特定值时会被触发	-
equals	某变量与期待值相等时被触发	-
expression	表达式为true时被触发	注意返回的字符串必须转化为布尔类型才能正确动作。
tag	TAG_NAME变量满足匹配模式时会被触发	-
not	当条件为false时会被触发	-
allOf	当所有嵌套条件均为true时会被触发	至少包含一个条件
anyOf	嵌套条件中至少有一个为true时会被触发	至少包含一个条件
triggeredBy	当前构建为指定方式所触发时	触发方式为：SCMTrigger/TimerTrigger/UpstreamCause等。

环境准备

本文使用Easypack的LTS Jenkins 2.167.1版，环境准备请参看

https://liumiaocn.blog.csdn.net/article/details/92764938

获取Jenkins-Crumb

使用如下示例代码获取Jenkins-Crumb,为使用API方式生成示例作准备。

liumiaocn:jenkins liumiao$ jenkins_host_url=http://localhost:32002
liumiaocn:jenkins liumiao$ user_passwd="root:liumiaocn"
liumiaocn:jenkins liumiao$ jenkins_crumb=`curl -u $user_passwd ${jenkins_host_url}'/crumbIssuer/api/xml?xpath=concat(//crumbRequestField,":",//crumb)' 2>/dev/null`
liumiaocn:jenkins liumiao$ echo $jenkins_crumb
Jenkins-Crumb:83d748ee92512c4dccd589aaa5c55a9a
liumiaocn:jenkins liumiao$

创建Job

使用如下代码示例创建Job

liumiaocn:jenkins liumiao$ ls demo/pipeline/when/config.xml
demo/pipeline/when/config.xml
liumiaocn:jenkins liumiao$ cat demo/pipeline/when/config.xml
<?xml version='1.1' encoding='UTF-8'?>
<flow-definition plugin="workflow-job@2.32">
  <actions>
    <org.jenkinsci.plugins.pipeline.modeldefinition.actions.DeclarativeJobAction plugin="pipeline-model-definition@1.3.8"/>
  </actions>
  <description>Pipeline Job Sample</description>
  <keepDependencies>false</keepDependencies>
  <properties>
    <hudson.plugins.jira.JiraProjectProperty plugin="jira@3.0.7"/>
    <com.dabsquared.gitlabjenkins.connection.GitLabConnectionProperty plugin="gitlab-plugin@1.5.12">
      <gitLabConnection></gitLabConnection>
    </com.dabsquared.gitlabjenkins.connection.GitLabConnectionProperty>
  </properties>
  <definition class="org.jenkinsci.plugins.workflow.cps.CpsFlowDefinition" plugin="workflow-cps@2.69">
  <script>pipeline {
    agent any 

    environment {
        ENVIRONMENT_TEST_FLAG = 'NO'
    }
    stages {
        stage('Init') { 
            steps { 
              script {
                BUILD_EXPRESSION = true
                DEPLOY_USER = 'liumiaocn'
              }
            }
        }
        stage('Build') { 
            when {
              expression { BUILD_EXPRESSION }
            }
            steps { 
                sh 'echo Build stage ...' 
            }
        }
        stage('Test'){
            when {
              environment name: 'ENVIRONMENT_TEST_FLAG',
              value: 'YES'
            }
            steps {
                sh 'echo Test stage ...' 
            }
        }
        stage('Deploy') {
            when {
              equals expected: 'liumiaocn', 
              actual: DEPLOY_USER
            }
            steps {
                sh 'echo Deploy stage ...' 
            }
        }
    }
  }</script>
  <sandbox>false</sandbox>
  </definition>
  <triggers/>
  <disabled>false</disabled>
</flow-definition>
liumiaocn:jenkins liumiao$ curl -X POST -u $user_passwd -H ${jenkins_crumb} -H "Content-Type:application/xml"  --data-binary  "@demo/pipeline/when/config.xml" ${jenkins_host_url}/createItem?name=pipeline_job_when
liumiaocn:jenkins liumiao$ echo $?
0
liumiaocn:jenkins liumiao$

Jenkinsfile说明

本文示例所使用的Jenkinsfile信息如下所示，内容非常简单易读，简单说明如下：

pipeline是结构，在其中可以指定agent和stages等相关信息
agent用于指定执行job的节点，any为不做限制
stages用与设定具体的stage
stage为具体的节点，比如本文示例中模拟实际的 Build（构建）、测试（Test）、部署（Deploy）的过程。
when 模块用于设定此stage是否执行

pipeline {
    agent any 

    environment {
        ENVIRONMENT_TEST_FLAG = 'NO'
    }
    stages {
        stage('Init') { 
            steps { 
              script {
                BUILD_EXPRESSION = true
                DEPLOY_USER = 'liumiaocn'
              }
            }
        }
        stage('Build') { 
            when {
              expression { BUILD_EXPRESSION }
            }
            steps { 
                sh 'echo Build stage ...' 
            }
        }
        stage('Test'){
            when {
              environment name: 'ENVIRONMENT_TEST_FLAG',
              value: 'YES'
            }
            steps {
                sh 'echo Test stage ...' 
            }
        }
        stage('Deploy') {
            when {
              equals expected: 'liumiaocn', 
              actual: DEPLOY_USER
            }
            steps {
                sh 'echo Deploy stage ...' 
            }
        }
    }
  }

执行Job

使用BlueOcean执行之后，结果信息如下所示
在这里插入图片描述

执行之后使用如下命令可以确认相关的执行日志信息

liumiaocn:jenkins liumiao$ curl -u $user_passwd ${jenkins_host_url}/job/pipeline_job_when/1/consoleText
Started by user root
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] node
Running on Jenkins in /data/jenkins/workspace/pipeline_job_when
[Pipeline] {
[Pipeline] withEnv
[Pipeline] {
[Pipeline] stage
[Pipeline] { (Init)
[Pipeline] script
[Pipeline] {
[Pipeline] }
[Pipeline] // script
[Pipeline] }
[Pipeline] // stage
[Pipeline] stage
[Pipeline] { (Build)
[Pipeline] sh
+ echo Build stage ...
Build stage ...
[Pipeline] }
[Pipeline] // stage
[Pipeline] stage
[Pipeline] { (Test)
Stage "Test" skipped due to when conditional
[Pipeline] }
[Pipeline] // stage
[Pipeline] stage
[Pipeline] { (Deploy)
[Pipeline] sh
+ echo Deploy stage ...
Deploy stage ...
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // withEnv
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
Finished: SUCCESS
liumiaocn:jenkins liumiao$

修改执行条件，将Init的stage中的设定值做如下修正，保证Build和Deploy不执行，只执行Test

变量	修改前	修改后
BUILD_EXPRESSION	true	false
ENVIRONMENT_TEST_FLAG	‘NO’	‘YES’
DEPLOY_USER	‘liumiaocn’	‘liumiao’

执行日志如下所示

liumiaocn:jenkins liumiao$ curl -u $user_passwd ${jenkins_host_url}/job/pipeline_job_when/2/consoleText
Started by user root
Running in Durability level: MAX_SURVIVABILITY
[Pipeline] Start of Pipeline
[Pipeline] node
Running on Jenkins in /data/jenkins/workspace/pipeline_job_when
[Pipeline] {
[Pipeline] withEnv
[Pipeline] {
[Pipeline] stage
[Pipeline] { (Init)
[Pipeline] script
[Pipeline] {
[Pipeline] }
[Pipeline] // script
[Pipeline] }
[Pipeline] // stage
[Pipeline] stage
[Pipeline] { (Build)
Stage "Build" skipped due to when conditional
[Pipeline] }
[Pipeline] // stage
[Pipeline] stage
[Pipeline] { (Test)
[Pipeline] sh
+ echo Test stage ...
Test stage ...
[Pipeline] }
[Pipeline] // stage
[Pipeline] stage
[Pipeline] { (Deploy)
Stage "Deploy" skipped due to when conditional
[Pipeline] }
[Pipeline] // stage
[Pipeline] }
[Pipeline] // withEnv
[Pipeline] }
[Pipeline] // node
[Pipeline] End of Pipeline
Finished: SUCCESS
liumiaocn:jenkins liumiao$

页面结果如下所示
在这里插入图片描述