Java tutorial
/* * Copyright 2002-2018 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.web.server.adapter; import java.util.Arrays; import java.util.HashSet; import java.util.Set; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import reactor.core.publisher.Mono; import org.springframework.context.ApplicationContext; import org.springframework.core.NestedExceptionUtils; import org.springframework.http.HttpStatus; import org.springframework.http.codec.ServerCodecConfigurer; import org.springframework.http.server.reactive.HttpHandler; import org.springframework.http.server.reactive.ServerHttpRequest; import org.springframework.http.server.reactive.ServerHttpResponse; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.web.server.ServerWebExchange; import org.springframework.web.server.WebHandler; import org.springframework.web.server.handler.WebHandlerDecorator; import org.springframework.web.server.i18n.AcceptHeaderLocaleContextResolver; import org.springframework.web.server.i18n.LocaleContextResolver; import org.springframework.web.server.session.DefaultWebSessionManager; import org.springframework.web.server.session.WebSessionManager; /** * Default adapter of {@link WebHandler} to the {@link HttpHandler} contract. * * <p>By default creates and configures a {@link DefaultServerWebExchange} and * then invokes the target {@code WebHandler}. * * @author Rossen Stoyanchev * @author Sebastien Deleuze * @since 5.0 */ public class HttpWebHandlerAdapter extends WebHandlerDecorator implements HttpHandler { /** * Dedicated log category for disconnected client exceptions. * <p>Servlet containers do not expose a notification when a client disconnects, * e.g. <a href="https://java.net/jira/browse/SERVLET_SPEC-44">SERVLET_SPEC-44</a>. * <p>To avoid filling logs with unnecessary stack traces, we make an * effort to identify such network failures on a per-server basis, and then * log under a separate log category a simple one-line message at DEBUG level * or a full stack trace only at TRACE level. */ private static final String DISCONNECTED_CLIENT_LOG_CATEGORY = "org.springframework.web.server.DisconnectedClient"; /** * Tomcat: ClientAbortException or EOFException * Jetty: EofException * WildFly, GlassFish: java.io.IOException "Broken pipe" (already covered) * <p>TODO: * This definition is currently duplicated between HttpWebHandlerAdapter * and AbstractSockJsSession. It is a candidate for a common utility class. * @see #isDisconnectedClientError(Throwable) */ private static final Set<String> DISCONNECTED_CLIENT_EXCEPTIONS = new HashSet<>( Arrays.asList("ClientAbortException", "EOFException", "EofException")); private static final Log logger = LogFactory.getLog(HttpWebHandlerAdapter.class); private static final Log disconnectedClientLogger = LogFactory.getLog(DISCONNECTED_CLIENT_LOG_CATEGORY); private WebSessionManager sessionManager = new DefaultWebSessionManager(); @Nullable private ServerCodecConfigurer codecConfigurer; @Nullable private LocaleContextResolver localeContextResolver; @Nullable private ApplicationContext applicationContext; public HttpWebHandlerAdapter(WebHandler delegate) { super(delegate); } /** * Configure a custom {@link WebSessionManager} to use for managing web * sessions. The provided instance is set on each created * {@link DefaultServerWebExchange}. * <p>By default this is set to {@link DefaultWebSessionManager}. * @param sessionManager the session manager to use */ public void setSessionManager(WebSessionManager sessionManager) { Assert.notNull(sessionManager, "WebSessionManager must not be null"); this.sessionManager = sessionManager; } /** * Return the configured {@link WebSessionManager}. */ public WebSessionManager getSessionManager() { return this.sessionManager; } /** * Configure a custom {@link ServerCodecConfigurer}. The provided instance is set on * each created {@link DefaultServerWebExchange}. * <p>By default this is set to {@link ServerCodecConfigurer#create()}. * @param codecConfigurer the codec configurer to use */ public void setCodecConfigurer(ServerCodecConfigurer codecConfigurer) { Assert.notNull(codecConfigurer, "ServerCodecConfigurer must not be null"); this.codecConfigurer = codecConfigurer; } /** * Return the configured {@link ServerCodecConfigurer}. */ public ServerCodecConfigurer getCodecConfigurer() { return (this.codecConfigurer != null ? this.codecConfigurer : ServerCodecConfigurer.create()); } /** * Configure a custom {@link LocaleContextResolver}. The provided instance is set on * each created {@link DefaultServerWebExchange}. * <p>By default this is set to * {@link org.springframework.web.server.i18n.AcceptHeaderLocaleContextResolver}. * @param localeContextResolver the locale context resolver to use */ public void setLocaleContextResolver(LocaleContextResolver localeContextResolver) { this.localeContextResolver = localeContextResolver; } /** * Return the configured {@link LocaleContextResolver}. */ public LocaleContextResolver getLocaleContextResolver() { return (this.localeContextResolver != null ? this.localeContextResolver : new AcceptHeaderLocaleContextResolver()); } /** * Configure the {@code ApplicationContext} associated with the web application, * if it was initialized with one via * {@link org.springframework.web.server.adapter.WebHttpHandlerBuilder#applicationContext * WebHttpHandlerBuilder#applicationContext}. * @param applicationContext the context * @since 5.0.3 */ public void setApplicationContext(ApplicationContext applicationContext) { this.applicationContext = applicationContext; } /** * Return the configured {@code ApplicationContext}, if any. * @since 5.0.3 */ @Nullable public ApplicationContext getApplicationContext() { return this.applicationContext; } @Override public Mono<Void> handle(ServerHttpRequest request, ServerHttpResponse response) { ServerWebExchange exchange = createExchange(request, response); return getDelegate().handle(exchange).onErrorResume(ex -> handleFailure(request, response, ex)) .then(Mono.defer(response::setComplete)); } protected ServerWebExchange createExchange(ServerHttpRequest request, ServerHttpResponse response) { return new DefaultServerWebExchange(request, response, this.sessionManager, getCodecConfigurer(), getLocaleContextResolver(), this.applicationContext); } private Mono<Void> handleFailure(ServerHttpRequest request, ServerHttpResponse response, Throwable ex) { if (isDisconnectedClientError(ex)) { if (disconnectedClientLogger.isTraceEnabled()) { disconnectedClientLogger.trace("Looks like the client has gone away", ex); } else if (disconnectedClientLogger.isDebugEnabled()) { disconnectedClientLogger.debug("Looks like the client has gone away: " + ex + " (For a full stack trace, set the log category '" + DISCONNECTED_CLIENT_LOG_CATEGORY + "' to TRACE level.)"); } return Mono.empty(); } if (response.setStatusCode(HttpStatus.INTERNAL_SERVER_ERROR)) { logger.error("Failed to handle request [" + request.getMethod() + " " + request.getURI() + "]", ex); return Mono.empty(); } // After the response is committed, propagate errors to the server.. HttpStatus status = response.getStatusCode(); logger.error("Unhandled failure: " + ex.getMessage() + ", response already set (status=" + status + ")"); return Mono.error(ex); } private boolean isDisconnectedClientError(Throwable ex) { String message = NestedExceptionUtils.getMostSpecificCause(ex).getMessage(); message = (message != null ? message.toLowerCase() : ""); String className = ex.getClass().getSimpleName(); return (message.contains("broken pipe") || DISCONNECTED_CLIENT_EXCEPTIONS.contains(className)); } }