The DispatcherHandler now has an errorMapper property that is a
function for transforming errors. By default this property is set to an
instance of DispatcherHandlerExceptionMapper which wraps "standard"
framework exceptions and @ResponseStatus-annotated exceptions as
ResponseStatusException.
This makes it easy to handle the exceptions downstream uniformly.
This change adds a ResponseStatusException to associate an exception
with a status code at runtime. Along with that is an
ResponseStatusExceptionHandler that handles ResponseStatusException
by setting the response status.
General improvements e.g. make use of Java 8 Stream. The main reason
for the refactoring however to tighten error handling. To that extent:
InvocableHandlerMethod turns all exceptions into Reactive Streams
error signals, in effect never allowing any Exceptions to bubble up.
HandlerMethodArgumentResolver may throw an Exception for sync resolution
or produce an error signal via the returned Publisher. Either way the
exception is consistently wrapped with helpful method argument details.
For the latter case using a custom mapError operator.
HandlerMethodArgumentResolver no longer needs to return Optional for
nullable argument values. Instead (for now) the defaultIfEmpty operator
of reactor.rx.Stream operator is used to ensure a default constant value
(called "NO_VALUE") is produced. That way an argument resolver may
produce 0..1 values where 0 means it did not resolve to any value and
that results in null passed as the argument value.
If a HandlerMethodArgumentResolver produces more than one value, all
additional values beyond the first one will be ignored with the help
of a custom "first" operator.
As HandlerMethod is invoked within the map operator, checked exceptions
are not allowed but instead of wrapping it in a runtime exception what
we really need is to unwrap the target exception for exception
resolution purposes. To this end concatMap is used to produce a nested
Publisher or an error Publisher with the unwrapped target exception.
Related to that InvocableHandlerMethod now returns
Publisher<HandlerResult> instead of Publisher<Object> so that no longer
needs to be externally mapped from Object to HandlerResult.
InvocableHandlerMethodTests provides tests for the above scenarios and
verifies the details of resulting error signals.
This is needed in order to be able to use Spring Reactive in standalone
applications. These are temporary classes that will return in
src/test/java when Spring Boot support for Reactive applications will
be implemented.
reactive.codec -> core.codec
reactive.io -> util
These may very well not be the final locations. For now they simply
express that there are classes that belong somewhere in core, i.e.
they are lower level dependencies than web.
RequestMappingHandlerMapping currently picks the first match and does
have logic to deal with selecting the best match. This caused a
random test failure depending on which controller method was matched
first. This change removes the test.
The web related code is now under org.springframework.web.reactive.
This is parallel to org.springframework.web (the top-level package of
spring-webmvc).
This change allows to be able to check generic type on the return value
at HandlerAdapter and ResultHandler level. For example, it allows to do
a Publisher<Void> check in SimpleHandlerResultHandler.
This commit introduces the following changes:
- MessageToByteEncoder/Decoder renamed to Encoder/Decoder
- JsonObjectEncoder/Decoder are now used directly in
JacksonJsonEncoder/Decoder
- Codec uses MimeType instead of MediaType since they
are not specific to HTTP
- Default MimeType are now managed thanks to
Encoder/Decoder#getSupportedMimeTypes()
- AbstractEncoder/Decoder takes care of generic MimeType related behavior
This commit introduces the following changes:
- Publisher -> Observable/Stream/etc. conversion is now managed
in a dedicated ConversionService instead of directly in
RequestBodyArgumentResolver and ResponseBodyResultHandler
- More isolated logic that decides if the stream should be
serialized as a JSON array or not
- Publisher<ByteBuffer> are now handled by regular
ByteBufferEncoder and ByteBufferDecoder
- Handle Publisher<Void> return value properly
- Ensure that the headers are properly written even for response
without body
- Improve JsonObjectEncoder to autodetect JSON arrays
This commit updates HandlerAdapter#handle() to return HandlerResult
instead of Publisher<HandlerResult>. A new SimpleHandlerResultHandler
class has been introduced for handlers returning Publisher<Void>.
