IntelliQ IT Training Institute

Jenkins
=============
This is a tool for implementing CI-CD

Stage in CI-CD
=====================
Stage 1 (Continuous Download)
The code created by developers is uplaoded into some version
controlling system like Git.The moment code is uplaoded into
Git jenkins will get a notification and Jenkins will download
that code.This is called Continuous Download

Stage 2 (Continuous Build)
The code downloaded in the previous stage has to be converted into
an artifact and using build tools like Ant,Maven,Gradle etc.
Jenkins will take the help of the above build pligins and create
an artifact.This artifact can come in the format of war,ear,exe file

Stage 3(Continuous Deployment)
The artifact created in the previous stage has to deployed into the 
Testing server where a team of testers can check if the application
is working accoring to the end users requirements.These testing servers
might be running on some application servers like tomcat,Weblogic,Jboss etc
Jenkins will deploy the artifact into the testing servers and this is
called Continuous Depoloyment

Stage 4 (Continuous Testing)
Jenkins will now run the automation test scripts created by the testers
and check if the applicaiton is working correctly or not.These automation
test scripts could be created by testers using tools like selenium,uft,Codedui
etc.Jenkins will run these test scripts and if the testing fails Jenkins will
send email notifications to developerts and testers.Developers fix the bugs and
uplaod the modified code into the version controlling system and JEnkins will
start from stage 1

Stage 5 (Continuous Delivery)
If testing passes Jenkins will deploy the application the production servers
where the client or the ned user can start accessing it.Thid is generally 
done by jenkins after taking interactive approvals from the Delivery team.



Setup of Jenkins and Tomcats for CI-CD
==========================================
1 Signin into AWS
2 Create 3 AWS ubuntu 18 instances
3 NAme the first one as JenkinsServer,second one as QAServer
  and the last one as ProdServer


Setup of Jenkins on the JEnkinsServer AWS instance
=========================================================
1 Connect to Jenkinsserver AWS instance using git bash
2 Update the apt repository
  sudo apt-get update
3 Install java
  sudo apt-get install -y openjdk-8-jdk
4 Install git and maven
  sudo apt-get install -y git maven
5 Download jenkins.war
  wget http://mirrors.jenkins.io/war-stable/latest/jenkins.war
6 To start jenkins
  java -jar jenkins.war
7 To acces jenkins from a browser
  public_ip_of_jenkinserver:8080
8 Unlock Jenkins by entering the admin password
9 Click on Install Suggested plugins
10 Create first admin user--->Click Continue--->Click Save and Finish