Flux and Mono are used both for implementation and exposed at API
level to express 1 versus N semantic and to provide default Rx
operators:
- Flux<T> for multiple values Publisher (issue #48)
- Mono<T> for single value Publisher (issue #50)
- Mono<Void> for Publisher with no value (issue #49)
Prior to this change, a resource handler chain configured with a
`VersionResourceResolver` would add the resource version to the request
attributes when serving that resource. This approach would not work when
a `CachingResourceResolver` is configured and the resource is already
cached. Indeed, that code path is not executed when the resource is
resolved from the cache.
This commit adds a new `VersionedResource` interface that's used by the
`VersionResourceResolver`, adding a `getVersion()` method that returns
the version string for that resource. This way, the version information
is cached with the resource itself and the request attributes are no
longer used for this.
Issue: SPR-13817
For those runtimes that don't directly support Reacitve Streams this
commit separates more formally Reactive Streams bridge code out of
the request and response implementations which become simple adapters
to the ServerHttpRequest/Response contracts like their RxNetty and
Reactor Net counterparts.
ServerHttpResponse implementations now immediately propagate
HttpHeaders changes as they so there is no need to call applyHeaders().
The writeHeaders from ServerHttpResponse is also removed. RxNetty and
Reactor Net both support implicitly completing if the handler
completes without explicitly writing the headers or the response body.
Since ListenableFuture callbacks are invoked after the future is set,
we cannot rely on callbacks having taken place right after a call
to future.get(). This change adds a CountdownLatch to detect when
the callbacks were invoked.
Issue: SPR-12538
AsyncRequestExecution now properly supports decoration of the
request (URI, HTTP method, and headers).
Removed a no-op IdentityListenableFutureAdapter.
Use Spring Framework coding style.
Issue: SPR-12538
ConcurrentMapCacheManager and ConcurrentMapCache now support the
serialization of cache entries via a new `storeByValue` attribute. If it is
explicitly enabled, the cache value is first serialized and that content
is stored in the cache.
The net result is that any further change made on the object returned
from the annotated method is not applied on the copy held in the cache.
Issue: SPR-13758
