接口
ServerRequest
public interface ServerRequest {HttpMethod method();URI uri();UriBuilder uriBuilder();default String path() {return requestPath().pathWithinApplication().value();}default RequestPath requestPath() {return ServletRequestPathUtils.getParsedRequestPath(servletRequest());}Headers headers();MultiValueMap<String, Cookie> cookies();Optional<InetSocketAddress> remoteAddress();List<HttpMessageConverter<?>> messageConverters();<T> T body(Class<T> bodyType) throws ServletException, IOException;<T> T body(ParameterizedTypeReference<T> bodyType) throws ServletException, IOException;default <T> T bind(Class<T> bindType) throws BindException {return bind(bindType, dataBinder -> {});}<T> T bind(Class<T> bindType, Consumer<WebDataBinder> dataBinderCustomizer) throws BindException;default Optional<Object> attribute(String name) {Map<String, Object> attributes = attributes();if (attributes.containsKey(name)) {return Optional.of(attributes.get(name));}else {return Optional.empty();}}Map<String, Object> attributes();default Optional<String> param(String name) {List<String> paramValues = params().get(name);if (CollectionUtils.isEmpty(paramValues)) {return Optional.empty();}else {String value = paramValues.get(0);if (value == null) {value = "";}return Optional.of(value);}}MultiValueMap<String, String> params();MultiValueMap<String, Part> multipartData() throws IOException, ServletException;default String pathVariable(String name) {Map<String, String> pathVariables = pathVariables();if (pathVariables.containsKey(name)) {return pathVariables.get(name);}else {throw new IllegalArgumentException("No path variable with name \"" + name + "\" available");}}Map<String, String> pathVariables();HttpSession session();Optional<Principal> principal();HttpServletRequest servletRequest();default Optional<ServerResponse> checkNotModified(Instant lastModified) {Assert.notNull(lastModified, "LastModified must not be null");return DefaultServerRequest.checkNotModified(servletRequest(), lastModified, null);}default Optional<ServerResponse> checkNotModified(String etag) {Assert.notNull(etag, "Etag must not be null");return DefaultServerRequest.checkNotModified(servletRequest(), null, etag);}default Optional<ServerResponse> checkNotModified(Instant lastModified, String etag) {Assert.notNull(lastModified, "LastModified must not be null");Assert.notNull(etag, "Etag must not be null");return DefaultServerRequest.checkNotModified(servletRequest(), lastModified, etag);}static ServerRequest create(HttpServletRequest servletRequest, List<HttpMessageConverter<?>> messageReaders) {return new DefaultServerRequest(servletRequest, messageReaders);}static Builder from(ServerRequest other) {return new DefaultServerRequestBuilder(other);}// ...
}
Headers
interface Headers {List<MediaType> accept();List<Charset> acceptCharset();List<Locale.LanguageRange> acceptLanguage();OptionalLong contentLength();Optional<MediaType> contentType();@NullableInetSocketAddress host();List<HttpRange> range();List<String> header(String headerName);@Nullabledefault String firstHeader(String headerName) {List<String> list = header(headerName);return list.isEmpty() ? null : list.get(0);}HttpHeaders asHttpHeaders();
}
Builder
interface Builder {Builder method(HttpMethod method);Builder uri(URI uri);Builder header(String headerName, String... headerValues);Builder headers(Consumer<HttpHeaders> headersConsumer);Builder cookie(String name, String... values);Builder cookies(Consumer<MultiValueMap<String, Cookie>> cookiesConsumer);Builder body(byte[] body);Builder body(String body);Builder attribute(String name, Object value);Builder attributes(Consumer<Map<String, Object>> attributesConsumer);Builder param(String name, String... values);Builder params(Consumer<MultiValueMap<String, String>> paramsConsumer);Builder remoteAddress(InetSocketAddress remoteAddress);ServerRequest build();}
RequestPredicate
// RequestPredicates
@FunctionalInterface
public interface RequestPredicate {boolean test(ServerRequest request);default RequestPredicate and(RequestPredicate other) {return new RequestPredicates.AndRequestPredicate(this, other);}default RequestPredicate negate() {return new RequestPredicates.NegateRequestPredicate(this);}default RequestPredicate or(RequestPredicate other) {return new RequestPredicates.OrRequestPredicate(this, other);}default Optional<ServerRequest> nest(ServerRequest request) {return (test(request) ? Optional.of(request) : Optional.empty());}default void accept(RequestPredicates.Visitor visitor) {visitor.unknown(this);}
}
RouterFunction
// RouterFunctions
@FunctionalInterface
public interface RouterFunction<T extends ServerResponse> {Optional<HandlerFunction<T>> route(ServerRequest request);default RouterFunction<T> and(RouterFunction<T> other) {return new RouterFunctions.SameComposedRouterFunction<>(this, other);}default RouterFunction<?> andOther(RouterFunction<?> other) {return new RouterFunctions.DifferentComposedRouterFunction(this, other);}default RouterFunction<T> andRoute(RequestPredicate predicate, HandlerFunction<T> handlerFunction) {return and(RouterFunctions.route(predicate, handlerFunction));}default RouterFunction<T> andNest(RequestPredicate predicate, RouterFunction<T> routerFunction) {return and(RouterFunctions.nest(predicate, routerFunction));}default <S extends ServerResponse> RouterFunction<S> filter(HandlerFilterFunction<T, S> filterFunction) {return new RouterFunctions.FilteredRouterFunction<>(this, filterFunction);}default void accept(RouterFunctions.Visitor visitor) {visitor.unknown(this);}default RouterFunction<T> withAttribute(String name, Object value) {Assert.hasLength(name, "Name must not be empty");Assert.notNull(value, "Value must not be null");Map<String, Object> attributes = new LinkedHashMap<>();attributes.put(name, value);return new RouterFunctions.AttributesRouterFunction<>(this, attributes);}default RouterFunction<T> withAttributes(Consumer<Map<String, Object>> attributesConsumer) {Assert.notNull(attributesConsumer, "AttributesConsumer must not be null");Map<String, Object> attributes = new LinkedHashMap<>();attributesConsumer.accept(attributes);return new RouterFunctions.AttributesRouterFunction<>(this, attributes);}}
HandlerFilterFunction
@FunctionalInterface
public interface HandlerFilterFunction<T extends ServerResponse, R extends ServerResponse> {R filter(ServerRequest request, HandlerFunction<T> next) throws Exception;default HandlerFilterFunction<T, R> andThen(HandlerFilterFunction<T, T> after) {Assert.notNull(after, "HandlerFilterFunction must not be null");return (request, next) -> {HandlerFunction<T> nextHandler = handlerRequest -> after.filter(handlerRequest, next);return filter(request, nextHandler);};}default HandlerFunction<R> apply(HandlerFunction<T> handler) {Assert.notNull(handler, "HandlerFunction must not be null");return request -> this.filter(request, handler);}static <T extends ServerResponse> HandlerFilterFunction<T, T>ofRequestProcessor(Function<ServerRequest, ServerRequest> requestProcessor) {Assert.notNull(requestProcessor, "Function must not be null");return (request, next) -> next.handle(requestProcessor.apply(request));}static <T extends ServerResponse, R extends ServerResponse> HandlerFilterFunction<T, R>ofResponseProcessor(BiFunction<ServerRequest, T, R> responseProcessor) {Assert.notNull(responseProcessor, "Function must not be null");return (request, next) -> responseProcessor.apply(request, next.handle(request));}static <T extends ServerResponse> HandlerFilterFunction<T, T>ofErrorHandler(Predicate<Throwable> predicate, BiFunction<Throwable, ServerRequest, T> errorHandler) {Assert.notNull(predicate, "Predicate must not be null");Assert.notNull(errorHandler, "ErrorHandler must not be null");return (request, next) -> {try {T t = next.handle(request);if (t instanceof ErrorHandlingServerResponse response) {response.addErrorHandler(predicate, errorHandler);}return t;}catch (Throwable throwable) {if (predicate.test(throwable)) {return errorHandler.apply(throwable, request);}else {throw throwable;}}};}}
HandlerFunction
@FunctionalInterface
public interface HandlerFunction<T extends ServerResponse> {T handle(ServerRequest request) throws Exception;
}
ServerResponse
// AsyncServerResponse, EntityResponse<T>, RenderingResponse
public interface ServerResponse {HttpStatusCode statusCode();HttpHeaders headers();MultiValueMap<String, Cookie> cookies();@NullableModelAndView writeTo(HttpServletRequest request, HttpServletResponse response, Context context) throws ServletException, IOException;static BodyBuilder from(ServerResponse other) {return new DefaultServerResponseBuilder(other);}static ServerResponse from(ErrorResponse response) {return status(response.getStatusCode()).headers(headers -> headers.putAll(response.getHeaders())).body(response.getBody());}static BodyBuilder status(HttpStatusCode status) {return new DefaultServerResponseBuilder(status);}static BodyBuilder status(int status) {return new DefaultServerResponseBuilder(HttpStatusCode.valueOf(status));}static BodyBuilder ok() {return status(HttpStatus.OK);}static BodyBuilder created(URI location) {BodyBuilder builder = status(HttpStatus.CREATED);return builder.location(location);}static BodyBuilder accepted() {return status(HttpStatus.ACCEPTED);}static HeadersBuilder<?> noContent() {return status(HttpStatus.NO_CONTENT);}static BodyBuilder seeOther(URI location) {BodyBuilder builder = status(HttpStatus.SEE_OTHER);return builder.location(location);}static BodyBuilder temporaryRedirect(URI location) {BodyBuilder builder = status(HttpStatus.TEMPORARY_REDIRECT);return builder.location(location);}static BodyBuilder permanentRedirect(URI location) {BodyBuilder builder = status(HttpStatus.PERMANENT_REDIRECT);return builder.location(location);}static BodyBuilder badRequest() {return status(HttpStatus.BAD_REQUEST);}static HeadersBuilder<?> notFound() {return status(HttpStatus.NOT_FOUND);}static BodyBuilder unprocessableEntity() {return status(HttpStatus.UNPROCESSABLE_ENTITY);}static ServerResponse async(Object asyncResponse) {return AsyncServerResponse.create(asyncResponse);}static ServerResponse async(Object asyncResponse, Duration timeout) {return AsyncServerResponse.create(asyncResponse, timeout);}static ServerResponse sse(Consumer<SseBuilder> consumer) {return SseServerResponse.create(consumer, null);}static ServerResponse sse(Consumer<SseBuilder> consumer, Duration timeout) {return SseServerResponse.create(consumer, timeout);}// ...
}
HeadersBuilder
HeadersBuilder
是一個用于構建 HTTP 響應頭的鏈式構建器接口,支持添加和修改響應頭、Cookie、緩存控制、允許的方法、ETag、資源位置等常用 HTTP 頭部信息,并最終生成響應對象。
interface HeadersBuilder<B extends HeadersBuilder<B>> {B header(String headerName, String... headerValues);B headers(Consumer<HttpHeaders> headersConsumer);B cookie(Cookie cookie);B cookies(Consumer<MultiValueMap<String, Cookie>> cookiesConsumer);B allow(HttpMethod... allowedMethods);B allow(Set<HttpMethod> allowedMethods);B eTag(String eTag);B lastModified(ZonedDateTime lastModified);B lastModified(Instant lastModified);B location(URI location);B cacheControl(CacheControl cacheControl);B varyBy(String... requestHeaders);ServerResponse build();ServerResponse build(WriteFunction writeFunction);@FunctionalInterfaceinterface WriteFunction {@NullableModelAndView write(HttpServletRequest servletRequest, HttpServletResponse servletResponse) throws Exception;}}
BodyBuilder
BodyBuilder
是在 HeadersBuilder
基礎上擴展的接口,用于構建包含響應體(包括對象、模板渲染、流式數據等)的 HTTP 響應內容。
interface BodyBuilder extends HeadersBuilder<BodyBuilder> {BodyBuilder contentLength(long contentLength);BodyBuilder contentType(MediaType contentType);ServerResponse body(Object body);<T> ServerResponse body(T body, ParameterizedTypeReference<T> bodyType);ServerResponse render(String name, Object... modelAttributes);ServerResponse render(String name, Map<String, ?> model);ServerResponse stream(Consumer<StreamBuilder> streamConsumer);}
SseBuilder
SseBuilder
是用于構建并發送 Server-Sent Events(SSE) 的構建器接口,支持事件 ID、名稱、重試時間、注釋、數據發送,以及超時、異常和完成回調等控制邏輯。
interface SseBuilder {void error(Throwable t);void complete();SseBuilder onTimeout(Runnable onTimeout);SseBuilder onError(Consumer<Throwable> onError);SseBuilder onComplete(Runnable onCompletion);void send(Object object) throws IOException;void send() throws IOException;SseBuilder id(String id);SseBuilder event(String eventName);SseBuilder retry(Duration duration);SseBuilder comment(String comment);void data(Object object) throws IOException;}
StreamBuilder
StreamBuilder
是用于構建低層級響應流的構建器接口,支持向客戶端逐步寫入對象數據(可指定媒體類型)、刷新緩沖、注冊流控制回調,以及在出現異常或超時等情況時進行處理。
interface StreamBuilder {void error(Throwable t);void complete();StreamBuilder onTimeout(Runnable onTimeout);StreamBuilder onError(Consumer<Throwable> onError);StreamBuilder onComplete(Runnable onCompletion);StreamBuilder write(Object object) throws IOException;StreamBuilder write(Object object, @Nullable MediaType mediaType) throws IOException;void flush() throws IOException;}
Context
Context
接口定義了在 writeTo(HttpServletRequest, HttpServletResponse, Context)
方法中使用的上下文,提供用于響應體轉換的 HttpMessageConverter
列表。
interface Context {List<HttpMessageConverter<?>> messageConverters();
}
執行
推薦閱讀: [spring6: DispatcherServlet.doDispatch]-源碼分析
RouterFunctionMapping
public class RouterFunctionMapping extends AbstractHandlerMapping implements InitializingBean, MatchableHandlerMapping {@Nullableprivate RouterFunction<?> routerFunction;private List<HttpMessageConverter<?>> messageConverters = Collections.emptyList();private boolean detectHandlerFunctionsInAncestorContexts = false;public RouterFunctionMapping() {}public RouterFunctionMapping(RouterFunction<?> routerFunction) {this.routerFunction = routerFunction;}@Overridepublic void afterPropertiesSet() {if (this.routerFunction == null) {initRouterFunctions();}if (CollectionUtils.isEmpty(this.messageConverters)) {initMessageConverters();}if (this.routerFunction != null) {PathPatternParser patternParser = getPatternParser();if (patternParser == null) {patternParser = new PathPatternParser();setPatternParser(patternParser);}RouterFunctions.changeParser(this.routerFunction, patternParser);}}private void initRouterFunctions() {List<RouterFunction<?>> routerFunctions = obtainApplicationContext().getBeanProvider(RouterFunction.class).orderedStream().map(router -> (RouterFunction<?>) router).collect(Collectors.toList());ApplicationContext parentContext = obtainApplicationContext().getParent();if (parentContext != null && !this.detectHandlerFunctionsInAncestorContexts) {parentContext.getBeanProvider(RouterFunction.class).stream().forEach(routerFunctions::remove);}this.routerFunction = routerFunctions.stream().reduce(RouterFunction::andOther).orElse(null);logRouterFunctions(routerFunctions);}private void initMessageConverters() {List<HttpMessageConverter<?>> messageConverters = new ArrayList<>(4);messageConverters.add(new ByteArrayHttpMessageConverter());messageConverters.add(new StringHttpMessageConverter());messageConverters.add(new AllEncompassingFormHttpMessageConverter());this.messageConverters = messageConverters;}@Override@Nullableprotected Object getHandlerInternal(HttpServletRequest servletRequest) throws Exception {if (this.routerFunction != null) {// DefaultServerRequestServerRequest request = ServerRequest.create(servletRequest, this.messageConverters);HandlerFunction<?> handlerFunction = this.routerFunction.route(request).orElse(null);setAttributes(servletRequest, request, handlerFunction);return handlerFunction;}else {return null;}}private void setAttributes(HttpServletRequest servletRequest, ServerRequest request,@Nullable HandlerFunction<?> handlerFunction) {PathPattern matchingPattern =(PathPattern) servletRequest.getAttribute(RouterFunctions.MATCHING_PATTERN_ATTRIBUTE);if (matchingPattern != null) {servletRequest.removeAttribute(RouterFunctions.MATCHING_PATTERN_ATTRIBUTE);servletRequest.setAttribute(BEST_MATCHING_PATTERN_ATTRIBUTE, matchingPattern.getPatternString());ServerHttpObservationFilter.findObservationContext(request.servletRequest()).ifPresent(context -> context.setPathPattern(matchingPattern.getPatternString()));}servletRequest.setAttribute(BEST_MATCHING_HANDLER_ATTRIBUTE, handlerFunction);servletRequest.setAttribute(RouterFunctions.REQUEST_ATTRIBUTE, request);}@Nullable@Overridepublic RequestMatchResult match(HttpServletRequest request, String pattern) {throw new UnsupportedOperationException("This HandlerMapping uses PathPatterns");}
}
HandlerFunctionAdapter
public class HandlerFunctionAdapter implements HandlerAdapter, Ordered {private static final Log logger = LogFactory.getLog(HandlerFunctionAdapter.class);private int order = Ordered.LOWEST_PRECEDENCE;@Nullableprivate Long asyncRequestTimeout;public void setOrder(int order) {this.order = order;}@Overridepublic int getOrder() {return this.order;}public void setAsyncRequestTimeout(long timeout) {this.asyncRequestTimeout = timeout;}@Overridepublic boolean supports(Object handler) {return handler instanceof HandlerFunction;}@Nullable@Overridepublic ModelAndView handle(HttpServletRequest servletRequest, HttpServletResponse servletResponse, Object handler) throws Exception {WebAsyncManager asyncManager = getWebAsyncManager(servletRequest, servletResponse);servletResponse = getWrappedResponse(asyncManager);ServerRequest serverRequest = getServerRequest(servletRequest);ServerResponse serverResponse;if (asyncManager.hasConcurrentResult()) {serverResponse = handleAsync(asyncManager);}else {HandlerFunction<?> handlerFunction = (HandlerFunction<?>) handler;serverResponse = handlerFunction.handle(serverRequest);}if (serverResponse != null) {return serverResponse.writeTo(servletRequest, servletResponse, new ServerRequestContext(serverRequest));}else {return null;}}private WebAsyncManager getWebAsyncManager(HttpServletRequest servletRequest, HttpServletResponse servletResponse) {AsyncWebRequest asyncWebRequest = WebAsyncUtils.createAsyncWebRequest(servletRequest, servletResponse);asyncWebRequest.setTimeout(this.asyncRequestTimeout);WebAsyncManager asyncManager = WebAsyncUtils.getAsyncManager(servletRequest);asyncManager.setAsyncWebRequest(asyncWebRequest);return asyncManager;}private static HttpServletResponse getWrappedResponse(WebAsyncManager asyncManager) {AsyncWebRequest asyncRequest = asyncManager.getAsyncWebRequest();Assert.notNull(asyncRequest, "No AsyncWebRequest");HttpServletResponse servletResponse = asyncRequest.getNativeResponse(HttpServletResponse.class);Assert.notNull(servletResponse, "No HttpServletResponse");return servletResponse;}private ServerRequest getServerRequest(HttpServletRequest servletRequest) {ServerRequest serverRequest =(ServerRequest) servletRequest.getAttribute(RouterFunctions.REQUEST_ATTRIBUTE);Assert.state(serverRequest != null, () -> "Required attribute '" +RouterFunctions.REQUEST_ATTRIBUTE + "' is missing");return serverRequest;}@Nullableprivate ServerResponse handleAsync(WebAsyncManager asyncManager) throws Exception {Object result = asyncManager.getConcurrentResult();asyncManager.clearConcurrentResult();LogFormatUtils.traceDebug(logger, traceOn -> {String formatted = LogFormatUtils.formatValue(result, !traceOn);return "Resume with async result [" + formatted + "]";});if (result instanceof ServerResponse response) {return response;}else if (result instanceof Exception exception) {throw exception;}else if (result instanceof Throwable throwable) {throw new ServletException("Async processing failed", throwable);}else if (result == null) {return null;}else {throw new IllegalArgumentException("Unknown result from WebAsyncManager: [" + result + "]");}}@Override@SuppressWarnings("deprecation")public long getLastModified(HttpServletRequest request, Object handler) {return -1L;}private static class ServerRequestContext implements ServerResponse.Context {private final ServerRequest serverRequest;public ServerRequestContext(ServerRequest serverRequest) {this.serverRequest = serverRequest;}@Overridepublic List<HttpMessageConverter<?>> messageConverters() {return this.serverRequest.messageConverters();}}
}
實戰
@SpringBootApplication
public class Application {@Beanpublic RequestPredicate requestPredicate() {return RequestPredicates.GET("/");}@Beanpublic HandlerFunction<ServerResponse> handlerFunction() {return request -> ServerResponse.ok().body("hello, world");}@Beanpublic HandlerFilterFunction<ServerResponse, ServerResponse> handlerFilterFunction() {return (request, next) -> {System.out.println("Before handler");ServerResponse response = next.handle(request);System.out.println("After handler");return response;};}@Beanpublic RouterFunction<ServerResponse> routerFunction() {return RouterFunctions.route(requestPredicate(), handlerFunction()).filter(handlerFilterFunction());}public static void main(String[] args) {SpringApplication.run(Application.class, args);}}