Creating a CI/CD Pipeline for a NestJS Application on Azure

In today’s fast-paced software development landscape, Continuous Integration (CI) and Continuous Deployment (CD) are essential practices for delivering high-quality applications efficiently. For developers using NestJS—a progressive Node.js framework for building scalable server-side applications—setting up a CI/CD pipeline on Azure can streamline the deployment process, reduce errors, and enhance collaboration. In this article, we will explore the definitions, use cases, and actionable steps to create a CI/CD pipeline for a NestJS application on Azure.

What is CI/CD?

Continuous Integration (CI) refers to the practice of automating the integration of code changes from multiple contributors into a shared repository several times a day. This involves automated testing to ensure the new code doesn’t break existing functionality.

Continuous Deployment (CD) extends CI by automatically deploying all code changes to production after passing the testing phase. This process ensures that updates are delivered to users quickly and reliably.

Use Cases for CI/CD

• Faster Release Cycles: Rapidly deploy new features and bug fixes.
• Improved Code Quality: Automated testing catches bugs early in the development process.
• Collaboration: Multiple developers can work on the same project simultaneously without conflicts.
• Efficiency: Automation reduces manual interventions, saving time and resources.

Prerequisites

Before diving into the setup, ensure you have:

1. An Azure account (you can sign up for a free trial).
2. Node.js and NestJS installed on your local machine.
3. A source control system, preferably Git.
4. An existing NestJS application to work with.

Step-by-Step Guide to Setting Up Your CI/CD Pipeline

Step 1: Initialize Your NestJS Application

If you haven't already created a NestJS application, you can set one up using the Nest CLI:

npm i -g @nestjs/cli
nest new my-nest-app
cd my-nest-app

Step 2: Set Up Your Azure DevOps Project

1. Create a New Project:
2. Log in to Azure DevOps.

3. Click on "New Project" and fill in the details.

4. Create a Repository:

5. Navigate to "Repos" and create a new repository for your NestJS application.
6. Push your local NestJS application to this repository:

git init
git add .
git commit -m "Initial commit"
git remote add origin <YOUR_AZURE_REPO_URL>
git push -u origin master

Step 3: Configure Azure Pipelines

1. Create a Pipeline:
2. Go to "Pipelines" in Azure DevOps and click on "New Pipeline".
3. Select "GitHub" or "Azure Repos Git" as your source, depending on where your repository is hosted.

4. Choose the repository containing your NestJS application.

5. Define Your Pipeline YAML:

6. Azure DevOps uses YAML files to define the CI/CD process. Create a file named azure-pipelines.yml in the root of your repository with the following content:

trigger:
  branches:
    include:
      - master

pool:
  vmImage: 'ubuntu-latest'

steps:
- task: NodeTool@0
  inputs:
    versionSpec: '14.x'

- script: |
    npm install
    npm run build
  displayName: 'Install and Build'

- task: PublishBuildArtifacts@1
  inputs:
    PathtoPublish: 'dist'
    ArtifactName: 'drop'
    publishLocation: 'Container'

Step 4: Add Continuous Deployment

To deploy your NestJS application, you must define how to push the build artifacts to your Azure environment.

1. Create a Web App in Azure:
2. Go to the Azure portal and create a new Web App.

3. Choose the appropriate settings (like runtime stack and region).

4. Modify Your azure-pipelines.yml:

Add a deployment stage to your pipeline configuration:

- task: AzureWebApp@1
  inputs:
    azureSubscription: '<YOUR_AZURE_SUBSCRIPTION>'
    appName: '<YOUR_WEB_APP_NAME>'
    package: '$(System.DefaultWorkingDirectory)/**/drop/*.zip'

Step 5: Test Your CI/CD Pipeline

1. Commit Changes:

2. Make a change in your NestJS application and push it to the master branch.

3. Monitor the Pipeline:

4. Go back to Azure DevOps and monitor the pipeline's progress under "Pipelines".
5. Check for any build or deployment errors and resolve them accordingly.

Step 6: Troubleshooting Common Issues

• Build Failures: Ensure all dependencies are correctly specified in package.json. Use the command npm ci for a clean install.
• Deployment Failures: Check the Azure logs for any deployment errors and ensure the web app settings are correctly configured.
• Environment Variables: If your application requires environment variables, set them in the Azure portal under "Configuration" for your web app.

Conclusion

Setting up a CI/CD pipeline for your NestJS application on Azure is a powerful way to enhance your development workflow. By automating testing and deployment, you can focus more on writing code and less on the logistics of deployment. With the steps outlined in this guide, you can confidently create a robust CI/CD pipeline that supports your development needs.

Embrace the power of CI/CD and watch your productivity soar as you deliver high-quality applications faster than ever!