Tamil CI/CD Deploy An Application in Kubernetes Cluster Using Jenkins Pipeline Docker | InterviewDOT

Video Description

Click here - https://www.youtube.com/channel/UCd0U_xlQxdZynq09knDszXA?sub_confirmation=1 to get notifications. Tamil Deploy An Application in Kubernetes Cluster Using Jenkins Pipeline Docker | InterviewDOT Jenkins is an open source automation tool written in Java with plugins built for Continuous Integration purpose. Jenkins is used to build and test your software projects continuously making it easier for developers to integrate changes to the project, and making it easier for users to obtain a fresh build. They usually make shipping and deploying your application much easier. They make consistent testing much, much easier. Containerising your application is like shoving your app and all its dependencies into a box. Except the box is infinitely replicable. Whatever happens in the box, stays in the box - unless you explicitly take something out or put something in. And when it breaks, you'll just throw it away and get a new one. Containers make your app easy to run on different computers - ideally, the same image should be used to run containers in every environment stage from development to production. This post is your guide for building a Docker image, and then setting up Jenkins 2 to build and publish the image automatically, whenever you commit changes to your code repository. Requirements To run through this guide, you will need the following: To build and run the Docker image locally: Mac OS X or Linux, and Docker installed To set up Jenkins to build the image automatically: Access to a Jenkins 2.x installation Writing a Dockerfile To be able to build a Docker image with our app, we'll need a Dockerfile. You can think of it as a blueprint for Docker: it tells Docker what the contents and parameters of our image should be. Docker images are often based on other images. For this exercise, we are basing our image on the official Node Docker image. This makes our job easy, and our Dockerfile very short. The grunt work of installing Node and its dependencies in the image is already done in our base image; we'll just need to include our application. The Dockerfile is best stored with the code - this way any changes to it are versioned along with the actual application code. Building the image in Jenkins Now that we know our Docker image can be built, we'll want to do it automatically every time there is a change to the application code. For this, we'll use Jenkins. Jenkins is an automation server often used to build and deploy applications. Note: this guide assumes you are running Jenkins 2.0 or newer, with the Docker Pipeline plugin and Docker installed. If you don't have access to a Jenkins installation, refer to https://wiki.jenkins-ci.org/display/JENKINS/Installing+Jenkins PIPELINES AS CODE: THE JENKINSFILE Just like Dockerfiles, I'm a firm believer in storing Jenkins pipeline configuration as code, along with the application code. It generally makes sense to have everything in the same repository; the application code, what the build artifact should look like (Dockerfile), and how said artifact is created automatically (Jenkinsfile). We'll need to tell Jenkins what our stages are, and what to do in each one of them. For this we'll write a Jenkins Pipeline specification in a Jenkinsfile. That's the entirety of our pipeline specification for Jenkins. Now, we'll just need to tell Jenkins two things: Where to find our code What credentials to use to publish the Docker image We'll start by configuring the credentials: CONFIGURING DOCKER HUB WITH JENKINS To store the Docker image resulting from our build, we'll be using Docker Hub. You can sign up for a free account at https://hub.docker.com. We'll need to give Jenkins access to push the image to Docker Hub. For this, we'll create Credentials in Jenkins, and refer to them in the Jenkinsfile. As you might have noticed in the above Jenkinsfile, we're using docker.withRegistry to wrap the app.push commands - this instructs Jenkins to log in to a specified registry with the specified credential id (docker-hub-credentials). We have successfully containerised an application, and set up a Jenkins job to build and publish the image on every change to a repository. Great work! Next steps Now that we have set up a basic delivery pipeline, there are a few more things to consider. DEPLOYMENT The next logical step in the pipeline would be to deploy the container automatically into a testing environment. For this, we could use something like Amazon Elastic Container Service or Rancher. https://github.com/net-vinothkumar/cicd-k8s-demo.git