This commit introduces Protobuf support in WebFlux via dedicated
codecs.
Flux<Message> are serialized/deserialized using delimited Protobuf
messages with the size of each message specified before the message
itself. In that case, a "delimited=true" parameter is added to the
content type.
Mono<Message> are expected to use regular Protobuf message
format (without the size prepended before the message).
Related HttpMessageReader/Writer are automatically registered when the
"com.google.protobuf:protobuf-java" library is detected in the classpath,
and can be customized easily if needed via CodecConfigurer, for example
to specify protocol extensions via the ExtensionRegistry based
constructors.
Both "application/x-protobuf" and "application/octet-stream" mime types
are supported.
Issue: SPR-15776
Prior to this commit, controller handlers (regular and exception
handlers as well) would not overwrite existing HTTP response headers on
the exchange. This would lead to situations where Content-Type values
set during the initial handling phase would not be overwritten when
handling an error later on.
This commit aligns the implementation of that result handler on the
Spring MVC one in that regard.
Issue: SPR-17082
1. Revise @SubscribeMapping to address common points of confusion.
2. Add ExecutorSubsribableChannel.
3. Split Events and Interception in two.
Issue: SPR-16950
In order to be consistent with SPR-15776, and since it does not
provide clear added value, this commit deprecates
ExtensionRegistryInitializer and uses ExtensionRegistry
parameter instead in ProtobufHttpMessageConverter and
ProtobufJsonFormatHttpMessageConverter constructors.
Issue: SPR-17081
Introduces getBeanProvider(Class) and getBeanProvider(ResolvableType), also narrowing getBean(String, Class) and isTypeMatch(String, Class) to a non-null Class argument and enriching NoUniqueBeanDefinitionException with a full ResolvableType. In addition, ObjectProvider supports iterable/stream access for collection-style resolution of multiple matching beans now, and collection injection falls back to an empty collection in a single-constructor case with non-null arguments.
Issue: SPR-17075
Issue: SPR-11419
Issue: SPR-15338