Enable /actuator/openapi endpoint without requiring a different management port

[pdjohe]

Is your feature request related to a problem? Please describe.

• The actuator endpoints are only available if the management port is different.

Describe the solution you'd like

• Simply include the relevant API starter (either MVC or WebFlux) and configure management.endpoints.web.exposure.include=openapi to expose the openapi document endpoint (either only the application's openapi spec, or both the application's API and actuator API if springdoc.show-actuator=true).
• The current requirement of having a different management port for actuator endpoints is counter-intuitive and not how actuator endpoints are normally configured (I believe the @ConditionalOnEnabledEndpoint("openapi") can be leveraged to start up the actuator endpoints and other beans for actuator when required, and then @ConditionalOnMissingBean to fallback if actuator endpoints aren't enabled)
• These same above points should be applicable for /actuator/swagger-ui too, only needing to add swagger-ui to the management.endpoints.web.exposure.include list.

Describe alternatives you've considered

• I have tried copying and pasting OpenApiActuatorResource bean definition code into my project, and then set springdoc.enable-default-api-docs=false. The API works, but the swagger-ui isn't working.
• I also tried to set springdoc.api-docs.path=/actuator/openapibut the endpoint is not included in the actuator discovery endpoint response (/actuator) or other actuator config options since the configuration setup is not using proper actuator configuration.

[pdjohe]

Just to clarify, the documentation only says:

In order to display spring-boot-actuator endpoints, simply add the following property:

springdoc.show-actuator=true

This isn't the spring boot way to configure actuator. Config such as this make it difficult to use Spring's conditional annotations to properly wire actuator beans, as I mentioned in the description above.

But even if springdoc.show-actuator=true is set, it doesn't work (springdoc 3.0.1 with WebFlux). I see there are some beans that turn on if the management port is the same, but it doesn't make the actuator endpoints available.

Also, further down the documentation, this same property springdoc.show-actuator=true seems to be used for including actuator endpoints in the generated openapi documents. The property seems to be used two different ways (or at least documented with two different functionalities). But yes, when set, actuator endpoints are included in the generated openapi document.

Finally, I do see that there is a comment the documentation that say the ports need to be different, but I can't think of any other actuator endpoints that only work if management is run on a different port. I feel that should not be a prerequisite to use openapi actuator endpoints.