DevOps Classroom notes 21/Nov/2023

CI/CD Engine

• The idea of CI is to give feedback to developer about his recent change
• Steps: Whenever developer submits the code to git (push/pull request)
  • Build the code
  • Package the code
  • Execute the automated tests (unit tests/integration tests)
  • Run the static code analysis
    
• At any step if there is a failure, developer is supposed to rework i.e. his work is rejected.
• To perform this we need a software which can call the steps mentioned above. This software is called as CI/CD Engines
• Now lets look at a popular CI/CD Engine
  • Jenkins
• Installing jenkins Refer Here

How Jenkins works

• Jenkins Single Node
  
• In Jenkins Single Node on the linux machine a user called as jenkins will be created.
• Anything which we run from jenkins ui will be translated to low level linux commands executed as jenkins user.

Terms in Jenkins

• Job/Project: This is set of steps configured as one unit (Job/Project)
• Workspace
• Jenkins Home: This is home directory for the user jenkins which got created as part of jenkins installation.
  • Default on linux /var/lib/jenkins
  • Jenkins stores everything in jenkins home directory

Lets create a Project in Jenkins

• Create a jenkins free style project (UI/Classic) which shows the current user and environment variables
• For screenshots refer classroom video
  
  

Jenkins – Free Style Project

• This project is created with Jenkins UI
  
• The Sections are
  • General: Give metadata and basic settings
  • Source Code Management: Where the SCM (git details)
  • Build Triggers: When to build
  • Build Environment: Additonal environmental steps
  • Build Steps: Actual build steps
  • Post Build Actions: After success or failure what has to be done