ktomiwa/java-petclinic-simplified

Java Petclinic Simplified

Spring PetClinic with GitHub Actions on Azure

Deploying to Azure

We use Terraform to create an Azure resource group with a MySQL database and an Azure App Service web application.

You will probably want to customize your application name, and maybe your resource group name: edit the terraform/variables.tf for this.

To create your Azure resources, install Terraform and run it:

cd terraform
terraform init
terraform apply
cd ..

To delete your resources, you will also be able to use Terraform:

cd terraform
terraform destroy
cd ..

To deploy the application, you will need to edit the pom.xml and edit the azure-webapp-maven-plugin plugin section, in order to configure the resource group and the application name (which should be the same as the ones configured in Terraform).

Then, deploy the application by running:

./mvnw com.microsoft.azure:azure-webapp-maven-plugin:1.12.0:deploy

Use GitHub Actions

Set Up up your workflow

Create a service principal to deploy to Azure.

Important

Make sure you assign the name of your resource group to the variable AZ_RESOURCE_GROUP or substitute the value for it in the commands below. Replace yourServicePrincipalName with a name of your service principal you choose.

RESOURCE_ID=$(az group show --name "$AZ_RESOURCE_GROUP" --query id -o tsv)
az ad sp create-for-rbac --name "yourServicePrincipalName" --role contributor --scopes "$RESOURCE_ID" --sdk-auth

This command will return JSON - copy it and keep it safe as we'll use it in the next step:

{
  "clientId": "XXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXXX",
  "clientSecret": "XXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
  "subscriptionId": "XXXXXXXXX-XXXXX-XXXX-XXXX-XXXXXXXXXXXXX",
  "tenantId": "XXXXXXXX-XXXXX-XXXX-XXXX-XXXXXXXXXXX",
  ...
}

GitHub Secrets

Once you have the required ID and Secrets, the next step is to add them the secret store in your GitHub project.

GitHub repositories have a feature known as Secrets that allow you to store sensitive information related to a project. For this exercise, store three secrets – AZURE_CLIENT_ID, AZURE_CLIENT_SECRET, AZURE_SUBSCRIPTION_ID, and AZURE_TENANT_ID. You'll create these secrets because they'll be used by Terraform to authenticate to Azure.

To create the secrets, fork the GitHub repository, select the Settings menu and then on Secrets. Create a GitHub secret for each of four secrets using the values returned the Azure service principal.

Workflow file

Inside the project directory, you'll see a directory called .github/workflows and a file called main.yml in it. This file is a GitHub workflow and will use the secret we configured above to deploy the application to your Azure subscription.

In that file, you'll see the following content:

name: CI

on:
  push:
    branches: [ main ]
  pull_request:
    branches: [ main ]

  workflow_dispatch:
jobs:
  terraform:
    runs-on: ubuntu-latest

    env:
      ARM_CLIENT_ID: ${{ secrets.AZURE_CLIENT_ID }}
      ARM_CLIENT_SECRET: ${{secrets.AZURE_CLIENT_SECRET}}
      ARM_SUBSCRIPTION_ID: ${{ secrets.AZURE_SUBSCRIPTION_ID }}
      ARM_TENANT_ID: ${{ secrets.AZURE_TENANT_ID }}

    defaults:
      run:
        working-directory: ./terraform
    steps:
      - uses: actions/checkout@v2

      - name: Setup Terraform
        uses: hashicorp/setup-terraform@v1

      - name: Terraform Init
        run: terraform init

      - name: Terraform Plan
        run: terraform plan

      - name: Terraform Apply
        run: terraform apply -auto-approve

This workflow does the following actions:

• Check whether the configuration is formatted properly
• generate a plan for every pull requests
• apply the configuration when you update the GitHub branch

Your workflow will be triggered whenever code is pushed to the repository.

Test the GitHub Action

You can now manually trigger the GitHub Actions workflow by going to "Actions", then select the terraform workflow. Then, select the "Terraform" workflow. Notice how the "Terraform Init", "Terraform Plan" and "Terraform Validate" steps have been triggered. Verify your Azure App Instance is publicly available.

Deploy your application

Use Maven, to deploy to your Azure instance.

./mvnw com.microsoft.azure:azure-webapp-maven-plugin:1.12.0:deploy

Destroy your resources

Remove the resources:

terraform destroy

Each time you git push your code, your TerraForm provisioned resources are now automatically deployed to production.