Health Checks

Create default Health Check

The functional interface HealthCheck together with the annotations @Liveness and @Readiness are the key concepts to bring up a new health check. Following code snipping shows a very basic example on how to use the interface. The parameter isDefault with value true makes sure that this health check is covered during server startup (see section Settings in administration guide) and exposed to /health.

@Liveness(isDefault = true)
public class SampleHealthCheck implements HealthCheck{

    @Override
    public HealthCheckResponse call() {
        return HealthCheckResponse.named("sample-default")
                        .state(true)
                        .withData("key", "value")
                        .build();
    }

}

Important

Make sure to use @Liveness and @Readiness from package io.ox.proxy.health.impl otherwise health checks could not be registered.

Create custom Health Check Endpoint

To create a health check which should not be exposed via /health /health/live or /health/ready change health check´s default to false, create a new resource class with proper @PATH annotation and send health check´s response back to caller.

Custom Health Check:

@Liveness(isDefault = false)
public class SampleHealthCheck implements HealthCheck{

    @Override
    public HealthCheckResponse call() {
        return HealthCheckResponse.named("sample-custom")
                        .state(true)
                        .withData("key", "value")
                        .build();
    }

}

Custom Endpoint:

@Path("/custom")
public class SampleResource {

    @Path("/sample")
    @GET
    @Produces(MediaType.APPLICATION_JSON)
    public Response getCallHealthCheck() {
        // The Health Check to call
        return Response.ok().entity(new SampleHealthCheck().call()).build();
    }

}

Important

The SampleHealthCheck class can be placed in a package of your choise but make sure to place SampleResource in package io.ox.proxy.jersey.resource otherwise this resource could not be bind to JAX-RS context.