CI-CD_Piplines

Why Do We Need a CI/CD Pipeline?

• Modern software delivery involves:

  • Code writing

  • Testing

  • Building

  • Deployment

  • Repeated again and again (cycle)

• Doing this manually is:

  • Slow

  • Error-prone

  • Inconsistent

• Solution → Automation using CI/CD tools

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Structure

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Putting it All Together (The CI/CD Loop)

Idea → Write Code → Push to GitHub → Jenkins gets triggered → Run tests → Build Docker Image → Deploy → Monitor → Repeat

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This is part of the Software Development Life Cycle (SDLC):

• A circular flow where:

  • New features are added

  • Code is improved or debugged

  • New tests are run

  • New versions are deployed

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Automation Best Practice

• If you do it often → Automate it.

• If it’s one-time setup → Manual is okay.

  • Example: Installing pytest once manually is fine.

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What Is a Jenkins Trigger?

• Trigger: An automated condition to run a Jenkins job without manual click.

• Allows jobs to be executed:

  • On a schedule (like a cron job)

  • On a GitHub push

  • When another job completes

  • On build failure or success

• Purpose: Pure automation.

You know the flow of:

GitHub → Jenkins → Test → Build → Deploy

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Final CI/CD Pipeline Summary

Developer writes code → Pushes to GitHub → Jenkins detects change (trigger) → Pulls code → Runs tests (pytest) → Builds Docker image → (Optional) Push to Docker Hub → Deploys container → Pipeline complete

Docker Build

An automation technique