/*
* Copyright 2002-2015 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.handler;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import reactor.core.publisher.Mono;
import org.springframework.http.HttpStatus;
import org.springframework.web.server.WebExceptionHandler;
import org.springframework.web.server.WebHandler;
import org.springframework.web.server.ServerWebExchange;
/**
* WebHandler that can invoke a target {@link WebHandler} and then apply
* exception handling with one or more {@link WebExceptionHandler} instances.
*
* @author Rossen Stoyanchev
*/
public class ExceptionHandlingWebHandler extends WebHandlerDecorator {
private static Log logger = LogFactory.getLog(ExceptionHandlingWebHandler.class);
private final List<WebExceptionHandler> exceptionHandlers;
public ExceptionHandlingWebHandler(WebHandler delegate, WebExceptionHandler... exceptionHandlers) {
super(delegate);
this.exceptionHandlers = initList(exceptionHandlers);
}
private static List<WebExceptionHandler> initList(WebExceptionHandler[] list) {
return (list != null ? Collections.unmodifiableList(Arrays.asList(list)): Collections.emptyList());
}
/**
* Return a read-only list of the configured exception handlers.
*/
public List<WebExceptionHandler> getExceptionHandlers() {
return this.exceptionHandlers;
}
@Override
public Mono<Void> handle(ServerWebExchange exchange) {
Mono<Void> mono;
try {
mono = getDelegate().handle(exchange);
}
catch (Throwable ex) {
mono = Mono.error(ex);
}
for (WebExceptionHandler exceptionHandler : this.exceptionHandlers) {
mono = mono.otherwise(ex -> exceptionHandler.handle(exchange, ex));
}
return mono.otherwise(ex -> handleUnresolvedException(exchange, ex));
}
private Mono<? extends Void> handleUnresolvedException(ServerWebExchange exchange, Throwable ex) {
if (logger.isDebugEnabled()) {
logger.debug("Could not complete request", ex);
}
exchange.getResponse().setStatusCode(HttpStatus.INTERNAL_SERVER_ERROR);
return Mono.empty();
}
}