001/*
002 * Copyright 2002-2019 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.web.reactive.result.method.annotation;
018
019import java.util.List;
020
021import reactor.core.publisher.Mono;
022
023import org.springframework.core.MethodParameter;
024import org.springframework.core.ReactiveAdapterRegistry;
025import org.springframework.http.HttpEntity;
026import org.springframework.http.RequestEntity;
027import org.springframework.http.codec.HttpMessageReader;
028import org.springframework.http.server.reactive.ServerHttpRequest;
029import org.springframework.lang.Nullable;
030import org.springframework.web.reactive.BindingContext;
031import org.springframework.web.server.ServerWebExchange;
032
033/**
034 * Resolves method arguments of type {@link HttpEntity} or {@link RequestEntity}
035 * by reading the body of the request through a compatible
036 * {@code HttpMessageReader}.
037 *
038 * @author Rossen Stoyanchev
039 * @since 5.2
040 */
041public class HttpEntityMethodArgumentResolver extends AbstractMessageReaderArgumentResolver {
042
043        public HttpEntityMethodArgumentResolver(List<HttpMessageReader<?>> readers, ReactiveAdapterRegistry registry) {
044                super(readers, registry);
045        }
046
047
048        @Override
049        public boolean supportsParameter(MethodParameter parameter) {
050                return checkParameterTypeNoReactiveWrapper(parameter,
051                                type -> HttpEntity.class.equals(type) || RequestEntity.class.equals(type));
052        }
053
054        @Override
055        public Mono<Object> resolveArgument(
056                        MethodParameter parameter, BindingContext bindingContext, ServerWebExchange exchange) {
057
058                Class<?> entityType = parameter.getParameterType();
059                return readBody(parameter.nested(), parameter, false, bindingContext, exchange)
060                                .map(body -> createEntity(body, entityType, exchange.getRequest()))
061                                .defaultIfEmpty(createEntity(null, entityType, exchange.getRequest()));
062        }
063
064        private Object createEntity(@Nullable Object body, Class<?> entityType, ServerHttpRequest request) {
065                return (RequestEntity.class.equals(entityType) ?
066                                new RequestEntity<>(body, request.getHeaders(), request.getMethod(), request.getURI()) :
067                                new HttpEntity<>(body, request.getHeaders()));
068        }
069
070}