Integration of Git, Github and Jenkins and creating the Build Pipeline
TASK 2
1. Create container image that’s has Jenkins installed using dockerfile
2. When we launch this image, it should automatically starts Jenkins service in the container.
3. Create a job chain of job1, job2, job3 and job4 using build pipeline plugin in Jenkins
4. Job1 : Pull the Github repo automatically when some developers push repo to Github.
5. Job2 : By looking at the code or program file, Jenkins should automatically start the respective language interpreter installed image container to deploy code ( eg. If code is of PHP, then Jenkins should start the container that has PHP already installed ).
6. Job3 : Test your app if it is working or not.
7. Job4 : if app is not working , then send email to developer with error messages.
8. Create One extra job job5 for monitor : If container where app is running. fails due to any reson then this job should automatically start the container again.
Tools required-
- Redhat vm (I am using redhat version8)
- github
- Jenkins
- docker
Now let's start the task
Creating the docker container image in which we have installed jenkins
Create one folder and in that folder create one docker file. Here i mention all the required dependencies for the image that has jenkins pre installed.
FROM centos:latest RUN yum install wget -y RUN yum install net-tools -y RUN wget O/etc/yum.repos.d/jenkins.repo https://pkg.jenkins.io/redhat/jenkins.repo RUN rpm --import https://pkg.jenkins.io/redhat/jenkins.io.key RUN yum install java -y RUN yum install jenkins -y RUN yum install git -y RUN echo "jenkins ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers CMD java -jar /usr/lib/jenkins/jenkins.war
run command for creating the docker image
docker build -t <name of image>:<version> <filepath> //run this command to build the docker image.
To verify that your image is created or not use
docker images //This cmd shows images that are created by us.
As you can see above image has been created successfully.
Now we are launching one container through this image . This container have jenkins pre-installed.
docker run -it — previleged -p 3320:8080 -v /:/host task2:v1
-v /:/host — Here we are mounting the / directory of base os to this docker container because in future we require docker inside this docker container to launch some container.
As you can see container has been launched and jenkins services has been started. Here we have to provide the password that is mentioned at the time of launching the container.
Creating job1
The role of this job is to download the code from the github repository where developer push the code. Here is my github repository that havinh some HTML code.
We have to provide the URL of the github repository to the this jenkins of job where developer have uploaded the code . so that jenkins will go download from there.
Here I am using Poll SCM trigger. From this trigger jenkins will go to github in every one minute and check if developer has uploaded any new code.
rm -rf /host/web-repo mkdir /host/web-repo cp -r . /host/web-repo
Jenkins will first create one folder in this container where jenkins is running and copy the code inside this folder.
job2
By looking at the code or program file that jenkins have downloaded from github, Jenkins should automatically start the respective language interpreter installed image container to deploy code ( eg. If code is of PHP, then Jenkins should start the container that has PHP already installed ).
If the code is in HTML then jenkins will start the container that has HTML interpreter already installed.
At the time of launching the container we have to expose this container to the client so that it can connect to the website running on this container.
chroot /host /bin/bash <<"EOT export len=$(ls /web-repo | grep index | grep html | wc -1) if [$len -gt 0] then if docker ps | grep prod_deploy then docker rm -f prod deploy docker docker run -dit -p 8081: 80 -v /web-repo:/usr/local/apache2/htdocs --name prod_deploy httpd:lat docker run -dit -p 8081: 80 -v /web-repo:/usr/local/apache2/htdocs --name prod deploy httpd:lat fi fi EOT
Job3
Test your app if it is working or not. If app is not working , then send email to developer with error messages.
Here in email notification we have to provide following details for sending email to the developer.
SMTP Server — smtp.gmail.com
Default user e-mail suffix- @gmail.com
Smtp port — 465
user name and password of the email from which you want to send the email to the developer
After creating all the jobs , now we are installing one plugin “Build Pipeline” . This plugin will give one dynamic pipeline for visualizing the task and for seeing the functioning of the jobs that are dependent on each other in efficient way.
Build pipeline view:
