What is a jenkins Part-1

                                                                        Jenkins

1. What is a Jenkins ?

i) Jenkins is a tool that is used for automation, and it is an open-source tool.

ii) Jenkins  allows all the developers to build, test and deploy software.

iii) Jenkins tool written in Java programming language.

iv) Jenkins we can make a continuous integration and continuous delivery (CI/CD) of projects or end-to-endpoint automation.

2. How to install the Jenkins and which tools will be required for Jenkins install.

1. Java

2. Maven

3. Git

4. Sonarqube

5. Aritifcate.

6. Ansible 

Step 1: install java on linux.

1.We will be using open java for our demo, Get the latest version from http://openjdk.java.net/install/

2.yum install java-1.8 java-1.8.0-openjdk-devel

3.Confirm Java Version and set the java home

4.java -version

5.find /usr/lib/jvm/java-1.8* | head -n 3

6.JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-<Java version which seen in the above output>

7.export JAVA_HOME

8.PATH=$PATH:$JAVA_HOME

9.To set it permanently update your .bash_profile

# vi ~/.bash_profile

The output should be something like this,

[root@~]# java -version

openjdk version "1.8.0_151"

OpenJDK Runtime Environment (build 1.8.0_151-b12)

OpenJDK 64-Bit Server VM (build 25.151-b12, mixed mode)

Step 2: Jenkins Repository

# wget -O /etc/yum.repos.d/jenkins.repo   http://jenkins-ci.org/redhat/jenkins.repo

# rpm --import http://pkg.jenkins-ci.org/redhat/jenkins-ci.org.key

Step 3: Install Jenkins

# yum install Jenkins

Step 4: Start Jenkins

# /etc/init.d/jenkins start | stop | restart

# chkconfig jenkins on

Step 5: Verify Jenkins

# netstat -ntulp | grep 8080

# vim /etc/sysconfig/Jenkins

Default:

JENKINS_PORT="8080"

New:

JENKINS_PORT="8443"

Step 6: Access the Jenkins Web portal

Access the URL : http://<Ip-Address-of-your-Server>:8080

Admin password is created and stored in the log file  “/var/log/jenkins/jenkins.log“. Run the below command to get the password.

[root@jenkins ~]# grep -A 5 password /var/log/jenkins/jenkins.log

Copy the password and paste it in above windows and click on Continue..

In the next windows Select the option : Install suggested plugins

As we can see required plugin installation is in progress for Jenkins. Once it is done with plugin installation. It will ask to create Admin User

Click on Save and Finish

click on “Start using Jenkins”

Jenkins user  login  :-

Go to :- Manage Jenkins à Configure Global Security

Uncheck “Allow users to sign up”

User:-admin,  password:-admin

How to Create Jobs for Projects :-

Click “New Item”

Type :- Jobs Name à Freestyle Project à OK

Specify the Project Description

SVN Structure:- 

SVN Repo :- http://192.168.1.21:81/svn/repo_data

Three working  Directory in Repo :-

SVN  :- http://192.168.1.21:81/svn/repo_data/Project_name/{Trunk,Tag,Branch}

Code URL :- http://192.168.1.21:81/svn/repo_data/newsybytes/trunk/<code>newsybytes

# visudo

jenkins  ALL=NOPASSWD:/bin/chown , /bin/chmod , /usr/bin/rsync , /bin/cp

Global Variable Set :-

Manage Jenkins à configure system à Global properties 

Deployment Script :-

# vim /var/lib/Jenkins/test.sh

#!/bin/bash

date1=$(date +%d-%m-%Y-%T)

code_path="$WORKSPACE/$Deployment_name"

revision_no=$(svn info --username admin --password admin $SVN_URL --no-auth-cache | grep "Last Changed Rev:" | cut -d ":" -f2 | cut -d " " -f2)

last_commet=$(svn log -l 1 --username admin --password admin $SVN_URL --no-auth-cache)

echo "################# START BUILD ######################"

        mkfile=$(touch /tmp/revision_$Deployment_name)

        Rev_number=$(cat /tmp/revision_$Deployment_name)

        old_rev_no=$(echo "$Rev_number")

if [[ "$old_rev_no" == "$revision_no" ]];then

        echo -e "LAST SVN REVISION NO:- $revision_no\n"

        echo "LAST COMMIT :-"

        echo -e "$last_commet\n"

        echo -e "NO ANY UPDATE....!\n"

else

  delete_svn=$(find $code_path -name ".svn" -type d -exec rm -rf "{}" \; 2> /dev/null)

rc=$(sudo rsync -a --delete $code_path/$Deployment_name/ /var/www/html/$Deployment_name/)

        per=$(sudo chmod -R 777 /var/www/html/$Deployment_name)

        own=$(sudo chown -R root:root /var/www/html/$Deployment_name)

        echo "LAST COMMIT :-"

        echo -e "$last_commet\n"

        echo -e "PERVIOUS SVN REVISION NO:- $old_rev_no\n"

        echo -e "CURRENT SVN REVISION NO:- $revision_no\n"

        echo -e "DEPLOYMENT IS COMPLETED..\n"

        svn_no=$(echo "$revision_no" > /tmp/revision_$Deployment_name)

fi

echo "################# COMPLETED BUILD #####################"

#chmod  -R 777 /var/lib/Jenkins/test.sh

Mailing  Configuration:-

Manage Jenkins à configure System à Extended E-mail Notification

Manage Jenkins à configure System à E-mail Notification

Post-build Actions

Triggers à add Trigger à Always

Add à  Recipient List,    Developers

Apply à Save

Need to multiple parameter

plugin name :- active choices

1.General à select This project is parameterized àActive Choices Parameter

Name:- Env

Select :- Groovy script

return[

'',

'Production',

'Development',

'Test',

'Stage'

]

Fallback Script

Groovy Script ->

return['error']

Description->

Please select an Environment

Choice Type -> Single Select

Filter starts at -> 1

Add à Active Choices Reactive Parameter

Name -> Servers

Select Groovy Script à

if (Env.equals("Production")) {

return ["Prod01", "Prod02", "Prod03", "Prod04"]

} else if (Env.equals("Development")) {

return ["Dev01", "Dev02", "Dev03"]

} else if (Env.equals("Test")) {

return ["test01", "test02"]

} else {

return ["Unknown state"]

}

Fallback Script

Groovy Script ->

return ['script Error']

Choice Type -> Single Select

Referenced parameters -> Env

Filter starts at -> 1

Build :-

echo "$Env"

echo "$Servers"