Create a CI/CD pipeline in Azure DevOps using Terraform, Ansible, and BASH

Objectives

  1. Create a CI/CD pipeline for a Node.js web app
  2. Create a VM deployment group
  3. Register a VM to a VM deployment group
  4. Create a CI/CD pipeline task to deploy a Node.js web app to different VM deployment groups
  5. Add a trigger to an existing CI/CD pipeline
  6. Configure health checks using Azure Traffic Manager

Setup

Step 1. Create a GitHub Personal Access Token (PAT) for Azure DevOps to use and save it as an environment variable. Make sure it expires soon and only has the following scopes checked: repo, admin:repo_hook, and user. 

export AZURE_DEVOPS_EXT_GITHUB_PAT=""

Step 2. Create an Azure DevOps PAT with the Deployment Groups: Read & Manage and Release: Read scopes checked. 

export DEPLOYMENT_GROUP_PAT=""

Step 3. Set other variables. 

export AZURE_PIPELINE_AGENT_URL_LINUX="https://vstsagentpackage.azureedge.net/agent/3.227.2/vsts-agent-linux-x64-3.227.2.tar.gz"
export DEPLOYMENT_GROUP_PROD="Production"
export DEPLOYMENT_GROUP_QA="QA"
export DEPLOYMENT_GROUP_TAG=""
export PROJECT_ORG=""
export PROJECT_NAME=""

Step 4. Download the provided source code. If you get a "Permission denied (publickey)" error, make sure you created an SSH key pair and added the public key to your GitHub profile. If the repo doesn't include a CI/CD pipeline file, add it.

git clone git@github.com:cyberphor/somerepo.git
cd somerepo

Step 5. Verify you're using the correct Azure subscription.

az account show

Step 6. Execute the script provided. 

bash Start-DevOps.sh

Run Terraform

cd terraform/
terraform init
terraform plan
terraform apply
export ANSIBLE_USER=$(terraform output admin_username | tr -d '"')
cd ..

Create Your Deployment Groups

Text goes here.

Load Your SSH Key Into Memory

eval "$(ssh-agent -s)" # start the SSH authentication agent
ssh-add ~/.ssh/id_rsa  # add your SSH private key to the SSH authentication agent

Register Virtual Machines as Deployment Group Targets

cd ansible/
ansible-playbook playbook.yaml -i inventory.yaml --ssh-common-args='-o StrictHostKeyChecking=no'
cd ..

Create a Release Pipeline

Azure DevOps > Projects > (your project) * Releases * Empty job * Pipeline name: "Server Release" * Edit pipeline * Artifacts * (after adding an artifact, the source alias will be listed) * Source Type: Build * Project: (your project) * Source (build pipeline): (name of build pipeline; i.e., value stored in PIPELINE_NAME environment variable and used in Start-DevOps.sh script) * Default version: "Latest" * Source alias: (keep the default value provided) * Continuous deployment trigger * Enabled * Stages * QA * Pre-deployment conditions * Triggers: "After release" * "Deployment group job" (remove the task added by default) * Deployment group: "QA" (should be the same value stored in DEPLOYMENT_GROUP_QA environment variable) * Additional options: * Run this job: "Only when all previous jobs have succeeded" * Tasks * Bash * Display name: "Bash Script" * Type: Inline * Script: * sudo apt-get update && sudo apt-get install unzip * Extract Files * Display name: "Extract Files" * Archive file patterns: $(System.DefaultWorkingDirectory)/<artifact-alias>/drop/server.zip * Destination folder: $(System.DefaultWorkingDirectory)/<artifact-alias>/drop/server/ * Node.js tool installer * Version Spec: "10.x" * Bash * Display name: "Bash Script" * Type: Inline * Script: * cd $(System.DefaultWorkingDirectory)//drop/server/ * if [ -f ~/pid.txt ]; then kill -9 cat ~/pid.txt fi * nohup node app.js >> app.log 2>&1 & * echo $! > ~/pid.txt * Variables * process.clean = false (By default, when a release is complete, any process or script initiated by the release pipeline is cleaned and stopped. As we are starting the node server process in this release pipeline, we would want it to continue even after the release is complete so that the web app remains running.) * Production (clone the "QA" stage) * Pre-deployment conditions * Triggers: "After stage" * Stages: "QA" * Pre-deployment approval * Approvers: (your email) * Deployment group: "Production" (should be the same value stored inDEPLOYMENT_GROUP_PROD` environment variable)

References