Task 03: Application modernization

What you’ll do: Use GitHub Copilot app modernization to assess, remediate, and modernize the Spring Boot application in preparation to migrate the workload to AKS Automatic.

What you’ll learn: How GitHub Copilot app modernization works, demonstration of modernizing elements of legacy applications, and the modernization workflow.

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Next, let’s begin our modernization work.

1. Select GitHub Copilot app modernization extension.

   

Execute the assessment

Now that you have GitHub Copilot setup, you can use the assessment tool to analyze your Spring Boot PetClinic application using the configured analysis parameters.

1. Navigate the Extension Interface and select Migrate to Azure to begin the modernization process.

You can follow the progress of the upgrade by looking at the Terminal in vscode

Overview of the assessment

Assessment results are consumed by GitHub Copilot App Modernization (AppCAT). AppCAT examines the scan findings and produces targeted modernization recommendations to prepare the application for containerization and migration to Azure.

• target: the desired runtime or Azure compute service you plan to move the app to.
• capability: what technology to modernize the apps towards.
• mode: the analysis depth AppCAT should use.
• os: best practices tailored for specific operating systems that AppCAT should use when migrating applications (windows or Linux). For this lab we will not be focusing on it.

Targets

Capability

Analysis modes

Where to change these options

You can customize this report by editing the file at .github/appmod-java/appcat/assessment-config.yaml to change targets and modes.

For this lab, AppCAT runs with the following configuration:

appcat:
 - target:
     - azure-aks
     - azure-appservice
     - azure-container-apps
   mode: issue-only

If you want a broader scan (including dependency checks) change mode to full, or add/remove entries under target to focus recommendations on a specific runtime or Azure compute service.

Review the assessment results

After the assessment completes, you’ll get a success message in the GitHub Copilot chat summarizing what was accomplished:

The assessment analyzed the Spring Boot Petclinic application for cloud migration readiness and identified the following:

Key findings:

• 4 cloud readiness issues requiring attention (1)
• 1 Java upgrade opportunity for modernization (2)

Resolution approach: More than 80% of the identified issues can be automatically resolved through code and configuration updates using GitHub Copilot’s built-in app modernization capabilities (3).

Issue prioritization: Issues are categorized by urgency level to guide remediation efforts:

• Mandatory (Purple) - Critical issues that must be addressed before migration.
• Potential (Blue) - Performance and optimization opportunities.
• Optional (Gray) - Nice-to-have improvements that can be addressed later.

This prioritization framework ensures teams focus on blocking issues first while identifying opportunities for optimization and future enhancements.

Review specific findings

Select individual issues in the report to see detailed recommendations. In practice, you would review all recommendations and determine the set that aligns with your migration and modernization goals for the application.

For this lab, you’ll spend your time focusing on one modernization recommendation: updating the code to use modern authentication via Azure Database for PostgreSQL Flexible Server with Entra ID authentication.