Health and Info endpoints

We expect all Kotlin applications to provide health and info endpoints to indicate their current status. The endpoints are provided by Spring Actuator but a little work is required to populate them as per HMPPS standards.

/health

Spring Actuator provides a health endpoint to expose details about the health of your application. The HealthIndicator interface allows you to contribute to the health page. In your application you should include any external dependencies on the health page to tell upstream clients whether your service is healthy.

Dependent APIs

The Kotlin template comes with a health check for HMPPS Auth API. This uses the HealthPingCheck provided by the Kotlin library. You should follow this pattern for any other APIs you call.

Databases

We generally use Spring Data for interacting with databases. This plays nicely with Spring Actuator and gives us a free HealthIndicator which means the status of your database should automatically appear on the health page.

SQS Queues and Topics

We generally use our HMPPS SQS library for interacting with AWS SQS and SNS. This automatically creates HealthIndicators for any queues and topics so they should automatically appear on your health page.

Other Dependencies

For anything else you can easily create your own HealthIndicator instances to register dependencies on your health page.

Some examples to inspire you can be found here and here.

/info

Spring Actuator provides an info endpoint to expose general information about your application. The InfoContributor interface allows you to contribute to the info page.

Product ID

The only details you must add to the info page is your Product ID. This is required by the SRE team and is used in the Developer Portal.

As this is required in all applications we have a solution provided by the HMPPS Kotlin library.

If you don’t know your Product ID please contact the SRE team on Slack at #ask-prisons-digital-sre.