HealthIndicator does not return HTTP Status 503 for Status.DOWN

[matsev]

Currently HTTP status 200 is returned for Status.DOWN.

In the Spring Boot 1.1 release notes it is stated that:

By default Status.DOWN will create a 503; Status.UP will return 200.

Step by step:

• Create a simple web app configured with the actuator.
• Add a "down" health check:

@Component
public class DownHealthIndicator extends AbstractHealthIndicator {

    @Override
    protected void doHealthCheck(Health.Builder builder) throws Exception {
        builder.down();
    }
}

• Check the health status:

$ curl -i localhost:8080/health
HTTP/1.1 200 OK
[...]
{"status":"DOWN"}

Spring Boot version: 1.1.4.RELEASE

[matsev]

The problem is in the HealthMvcEndpoint. On line 58, the default values of the statusMapping will be overwritten by the a call from EndpointWebMvcAutoConfiguration line 160. The value being passed by this.healthMvcEndpointProperties.getMapping() is an empty map, because the HealthMvcEndpointProperties contains just an empty map. Probably, the problem could be solved by moving the setupDefaultStatusMapping() to the HealthMvcEndpointProperties, but I do not know what other implications that may have.

[matsev]

I have given this problem some more thought, and I think you'd better keep the status mapping in one place, e.g. HealthMvcEndpointProperties. By refactor this class into an interface and providing a conditional, default implementation, a concrete instance can be autowired into the HealthMvcEndpoint. Moreover, you should remove the addStatusMapping() methods and the setStatusMapping() method from the HealthMvcEndpoint. However, this suggestion has the disadvantage of breaking the existing APIs.

[cdupuis]

I fixed the code so that the default mapping will not be overridden if no custom mapping is provided. Could you please test one of the upcoming snapshots?

Thanks for the report.

[matsev]

Looks good, I have verified the code in my test project.

Related, how can one change the status code? For example, I guessed that one could add endpoints.health.DOWN=500 to the application.properties file if a 500 response is preferred instead of the 503 (or a 200 if one would revert to the current behavior) but that does not seem to work?

[philwebb]

@cdupuis Master is now on 1.2, Is this a candidate for a 1.1.x backport?

[matsev]

@cdupuis Can you show me how I can override the default HTTP status codes? There are a couple of verifications that I would like to do:

• If only Status.DOWN is overridden to return 500, then Status.OUT_OF_SERVICE should return the default 503.
• Similarly, if a custom Status is implemented and mapped to a HTTP status code, then one expects the default statuses to still return 503.

[cdupuis]

@matsev in order to map Status.DOWN to 500 you have to use the following in your application.properties:

endpoints.health.mapping.DOWN: INTERNAL_SERVER_ERROR

Currently the implementation assumes that all mappings are overridden once you configure custom mappings in your application.properties. Arguably that probably isn't the most convenient approach.

[cdupuis]

@philwebb once we finalise this here, I'll back port to 1.1.x.