Add an `DispatcherServletPath` interface which provides a much more
consistent way to discover the path of the main dispatcher servet.
Prior to this commit, auto-configurations would often make use of the
`ServerProperties` class to discover the dispatcher servlet path. This
mechanism isn't very explicit and also makes it hard for us to relocate
that property in Spring Boot 2.1.
This commit also reverts most of fddc9e9c7e since it is now clear that
the supporting multiple dispatcher servlet paths will be much more
involved that we originally anticipated.
Closes gh-13834
Previously, when a DispatcherServlet was registered via a
ServletRegistrationBean, the mappings endpoint did not expose any
information about it as it wasn't detected.
This commit fixes the detection of available DispatcherServlets in the
context so that the mappings endpoint include them all.
Closes gh-13186
This commit improves the for Actuator Metrics in WebClient.
Unlike the server couterpart of WebFlux, using a `retry` operator on a
`WebClient` pipeline does resubscribes to the whole chain.
The previous implementation recorded start time at the time of pipeline
build phase, but outside of it. This doesn't work since retrying the
same pipeline doesn't update the recorded start time and the duration of
sequential calls are cumulative.
This is now fixed using the Reactor `Context`, since we're now recording
the start time at subscription time and record metrics on `onNext` and
`onError` signals.
Closes gh-12228
Previously, a NullPointerException would occur when WebFluxTags
attempted to create a method Tag for a request with a non-standard
method.
This commit updates WebFluxTags to use getMethodValue(), which will
never return null, rather than getMethod(), which may return null,
when determining the tag's value for the given request.
Closes gh-13596
