Right now, customization of Micrometer's MeterRegistry requires loading of the following actuator class: org.springframework.boot.actuate.autoconfigure.metrics.MeterRegistryCustomizer
Since MeterRegistry is a core type of micrometer, it should be possible to configure this even if actuator is not in the classpath.
I'm not sure if the issue is better here or on micrometer itself, so feel free to tell me to move it.
One path is to copy the type MeterRegistryCustomizer into a core package and backport the actuator one to extend it.
Comment From: snicoll
@adriancole I am not sure I got that. MeterRegistryCustomizer is actually processed by the actuator auto-configuration so moving the type would leave you with a callback that nobody would actually invoke.
Comment From: codefromthecrypt
Main point is that micrometer can be in use without actuator, so you are right it doesn't make sense unless the config that processes it is also refactored.
Comment From: snicoll
Point taken. We've actually discussed this in the past but I am going to flag this to give it another go.
Comment From: bclozel
I think Spring Boot users are used to getting the actuator dependency for this. Since we considered this issue a lot has happened and now the entire Spring portfolio is instrumented. We could consider a different, independent starter but the feature/footprint difference vs. actuator would not be great for most users.
I'm declining this issue for now as a result. We'll reopen and reconsider this if our community describes uses cases that would need this.