Tuesday, October 17, 2023

Jenkins Scripted Pipeline - Create Jenkins Pipeline for Automating Builds, Code quality checks, Deployments to Tomcat - How to build, deploy WARs using Jenkins Pipeline - Build pipelines integrate with github, Sonarqube, Slack, JaCoCo, Nexus, Tomcat

 

Jenkins Scripted Pipeline - Create Jenkins Pipeline for Automating Builds, Code quality checks, Deployments to Tomcat - How to build, deploy WARs using Jenkins Pipeline - Build pipelines integrate with github, Sonarqube, Slack, JaCoCo, Nexus, Tomcat

What are Pipelines in Jenkins?

- Pipelines are better than freestyle jobs, you can write a lot of complex tasks using pipelines when compared to Freestyle jobs.
- You can see how long each stage takes time to execute so you have more control compared to freestyle.
- Pipeline is groovy based script that have set of plug-ins integrated for automating the builds, deployment and test execution.
- Pipeline defines your entire build process, which typically includes stages for building an application, testing it and then delivering it. 
 - You can use snippet generator to generate pipeline code for the stages you don't know how to write groovy code.
- Pipelines are two types - Scripted pipeline and Declarative pipeline. Click here to know the difference between them.

Pre-requisites:
Install plug-ins
1. Install Deploy to container, Slack, Jacoco, Nexus Artifact Uploader and SonarQube plug-ins (if already installed, you can skip it)

Steps to Create Scripted Pipeline in Jenkins

1. Login to Jenkins

2. Create a New item

3. Give name as MyfirstPipelineJob and choose pipeline

4. Click ok. Pipeline is created now

5. Under build triggers, click on poll SCM, schedule as

H/02 * * * *

6. Go to Pipeline definition section, click on Pipeline syntax link. under sample step drop down, choose checkout: Checkout from version control. enter bitbucket or GitHub Repository URL, and enter right credentials. Click here to learn to use PAT if you are using GitHub. scroll down, click on Generate Pipeline script. Copy the code.

7. Now copy the below pipeline code highlighted section into Pipeline section in the pipeline. Please copy stage by stage

8. Change Maven3, SonarQube variables and also Slack channel name as highlighted above in red as per your settings.

9. For Nexus Upload stage, You need to change the Nexus URL and credentials ID for Nexus (which you can grab from Credentials tab after login)

10. For Dev Deploy stage, you can copy credentials ID used for connecting to Tomcat.


Pipeline Code:

node {

    def mvnHome = tool 'Maven3'
    stage ("checkout")  {
       copy code here which you generated from step #6
    }

   stage ('build')  {
    sh "${mvnHome}/bin/mvn clean install -f MyWebApp/pom.xml"
    }

     stage ('Code Quality scan')  {
       withSonarQubeEnv('SonarQube') {
       sh "${mvnHome}/bin/mvn -f MyWebApp/pom.xml sonar:sonar"
        }
   }
  
   stage ('Code coverage')  {
       jacoco()
   }

   stage ('Nexus upload')  {
        nexusArtifactUploader(
        nexusVersion: 'nexus3',
        protocol: 'http',
        nexusUrl: 'nexus_url:8081',
        groupId: 'myGroupId',
        version: '1.0-SNAPSHOT',
        repository: 'maven-snapshots',
        credentialsId: '2c293828-9509-49b4-a6e7-77f3ceae7b39',
        artifacts: [
            [artifactId: 'MyWebApp',
             classifier: '',
             file: 'MyWebApp/target/MyWebApp.war',
             type: 'war']
        ]
     )
    }
   
   stage ('DEV Deploy')  {
      echo "deploying to DEV Env "
      deploy adapters: [tomcat9(credentialsId: '4c55fae1-a02d-4b82-ba34-d262176eeb46', path: '', url: 'http://your_tomcat_url:8080')], contextPath: null, war: '**/*.war'

    }

  stage ('Slack notification')  {
    slackSend(channel:'channel-name', message: "Job is successful, here is the info -  Job '${env.JOB_NAME} [${env.BUILD_NUMBER}]' (${env.BUILD_URL})")
   }

   stage ('DEV Approve')  {
            echo "Taking approval from DEV Manager for QA Deployment"     
            timeout(time: 7, unit: 'DAYS') {
            input message: 'Do you approve QA Deployment?', submitter: 'admin'
            }
     }

stage ('QA Deploy')  {
     echo "deploying into QA Env " 
deploy adapters: [tomcat9(credentialsId: '4c55fae1-a02d-4b82-ba34-d262176eeb46', path: '', url: 'http://your_tomcat_url:8080')], contextPath: null, war: '**/*.war'

}

  stage ('QA notify')  {
    slackSend(channel:'channel-name', message: "QA Deployment was successful, here is the info -  Job '${env.JOB_NAME} [${env.BUILD_NUMBER}]' (${env.BUILD_URL})")
   }

stage ('QA Approve')  {
    echo "Taking approval from QA manager"
    timeout(time: 7, unit: 'DAYS') {
        input message: 'Do you want to proceed to PROD Deploy?', submitter: 'admin,manager_userid'
  }
}

stage ('PROD Deploy')  {
     echo "deploying into PROD Env " 
deploy adapters: [tomcat9(credentialsId: '4c55fae1-a02d-4b82-ba34-d262176eeb46', path: '', url: 'http://your_tomcat_url:8080')], contextPath: null, war: '**/*.war'

}
}

11. Click Apply, Save
12. Now click on Build. It should execute all the stages and show pipeline view like this.


Jenkins Nexus Integration - How to integrate Nexus with Jenkins

 

Jenkins Nexus Integration - How to integrate Nexus with Jenkins

 


You need to install Nexus Artifact Uploader plug-in to integrate Nexus with Jenkins. Let us see how to integrate Jenkins with Nexus and able to upload War/Ear/Jar/Exe/DLLs.


Pre-requistes:

Install Nexus Artifact Uploader plugin in Jenkins.


Steps:

1. Once you installed the above plug-ins, click existing FreeStyle job configuration or create a new job.

2. Under source code management. enter bitbucket repo url and git credentials.

3. Go to build section, add Maven targets. with goals clean install. Also click advance, give path of POM.xml



4. click on Add build step, choose Nexus artifact uploader.


6. Click on Apply, Save.



7. Now login to Nexus repo, Click on Components, Click on maven-snapshots


8. you shall see the WAR being uploaded here.

How to Install Nexus on RedHat Linux

 

How to Install Nexus on RedHat Linux

Nexus is binary repository manager, used for storing build artifacts. We will eventually integrate Nexus with Jenkins for uploading WAR/EAR/JAR files there.

Here are the steps for installing Sonatype Nexus 3 in RHEL in EC2 on AWS. Please create a new Redhat EC2 instance with small type. Choose Redhat Enterprise 8.



Pre-requisites:
Make sure you open port 8081 in AWS security group

Installation Steps:

sudo yum install wget -y









Download Open JDK

sudo yum install java-1.8.0-openjdk.x86_64 -y

Execute the below command to navigate to /opt directory by changing directory:
cd /opt

Download Nexus
sudo wget http://download.sonatype.com/nexus/3/nexus-3.23.0-03-unix.tar.gz

Extract Nexus
sudo tar -xvf nexus-3.23.0-03-unix.tar.gz
sudo mv nexus-3.23.0-03 nexus

Create a user called Nexus
sudo adduser nexus

Change the ownership of nexus files and nexus data directory to nexus user.
sudo chown -R nexus:nexus /opt/nexus

sudo chown -R nexus:nexus /opt/sonatype-work

Configure to run as Nexus user
change as below screenshot by removing # and adding nexus
 sudo vi /opt/nexus/bin/nexus.rc


Modify memory settings in Nexus configuration file
sudo vi /opt/nexus/bin/nexus.vmoptions

Modify the above file as shown in red highlighted section:














-Xms512m
-Xmx512m
-XX:MaxDirectMemorySize=512m

after making changes, press wq! to come out of the file.

Configure Nexus to run as a service

sudo vi /etc/systemd/system/nexus.service
Copy the below content highlighted in green color.

[Unit]
Description=nexus service
After=network.target
[Service]
Type=forking
LimitNOFILE=65536
User=nexus
Group=nexus
ExecStart=/opt/nexus/bin/nexus start
ExecStop=/opt/nexus/bin/nexus stop
User=nexus
Restart=on-abort
[Install]
WantedBy=multi-user.target

Create a link to Nexus
sudo ln -s /opt/nexus/bin/nexus /etc/init.d/nexus

Execute the following command to add nexus service to boot.

sudo chkconfig --add nexus
sudo chkconfig --levels 345 nexus on


Start Nexus
sudo service nexus start










Check whether Nexus service is running
sudo service nexus status

Check the logs to see if Nexus is running
tail -f /opt/sonatype-work/nexus3/log/nexus.log

You will see Nexus started..
If you Nexus stopped, review the steps above.

Now press Ctrl C to come out of this windows.

Once Nexus is successfully installed, you can access it in the browser by URL - http://public_dns_name:8081

Click on Sign in link
user name is admin and password can be found by executing below command:

sudo cat /opt/sonatype-work/nexus3/admin.password



Copy the password and click sign in.
Now setup admin password as admin123

you should see the home page of Nexus:


Jenkins Scripted Pipeline - Create Jenkins Pipeline for Automating Builds, Code quality checks, Deployments to Tomcat - How to build, deploy WARs using Jenkins Pipeline - Build pipelines integrate with github, Sonarqube, Slack, JaCoCo, Nexus, Tomcat

  Jenkins Scripted Pipeline - Create Jenkins Pipeline for Automating Builds, Code quality checks, Deployments to Tomcat - How to build, depl...