001/* 002 * Copyright 2002-2016 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; 018 019import reactor.core.publisher.Mono; 020 021import org.springframework.web.server.ServerWebExchange; 022 023/** 024 * Interface to be implemented by objects that define a mapping between 025 * requests and handler objects. 026 * 027 * @author Rossen Stoyanchev 028 * @author Sebastien Deleuze 029 * @since 5.0 030 */ 031public interface HandlerMapping { 032 033 /** 034 * Name of the {@link ServerWebExchange#getAttributes() attribute} that 035 * contains the mapped handler for the best matching pattern. 036 */ 037 String BEST_MATCHING_HANDLER_ATTRIBUTE = HandlerMapping.class.getName() + ".bestMatchingHandler"; 038 039 /** 040 * Name of the {@link ServerWebExchange#getAttributes() attribute} that 041 * contains the best matching pattern within the handler mapping. 042 */ 043 String BEST_MATCHING_PATTERN_ATTRIBUTE = HandlerMapping.class.getName() + ".bestMatchingPattern"; 044 045 /** 046 * Name of the {@link ServerWebExchange#getAttributes() attribute} that 047 * contains the path within the handler mapping, in case of a pattern match 048 * such as {@code "/static/**"} or the full relevant URI otherwise. 049 * <p>Note: This attribute is not required to be supported by all 050 * HandlerMapping implementations. URL-based HandlerMappings will 051 * typically support it but handlers should not necessarily expect 052 * this request attribute to be present in all scenarios. 053 */ 054 String PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE = HandlerMapping.class.getName() + ".pathWithinHandlerMapping"; 055 056 /** 057 * Name of the {@link ServerWebExchange#getAttributes() attribute} that 058 * contains the URI templates map mapping variable names to values. 059 * <p>Note: This attribute is not required to be supported by all 060 * HandlerMapping implementations. URL-based HandlerMappings will 061 * typically support it, but handlers should not necessarily expect 062 * this request attribute to be present in all scenarios. 063 */ 064 String URI_TEMPLATE_VARIABLES_ATTRIBUTE = HandlerMapping.class.getName() + ".uriTemplateVariables"; 065 066 /** 067 * Name of the {@link ServerWebExchange#getAttributes() attribute} that 068 * contains a map with URI variable names and a corresponding MultiValueMap 069 * of URI matrix variables for each. 070 * <p>Note: This attribute is not required to be supported by all 071 * HandlerMapping implementations and may also not be present depending on 072 * whether the HandlerMapping is configured to keep matrix variable content 073 * in the request URI. 074 */ 075 String MATRIX_VARIABLES_ATTRIBUTE = HandlerMapping.class.getName() + ".matrixVariables"; 076 077 /** 078 * Name of the {@link ServerWebExchange#getAttributes() attribute} containing 079 * the set of producible MediaType's applicable to the mapped handler. 080 * <p>Note: This attribute is not required to be supported by all 081 * HandlerMapping implementations. Handlers should not necessarily expect 082 * this request attribute to be present in all scenarios. 083 */ 084 String PRODUCIBLE_MEDIA_TYPES_ATTRIBUTE = HandlerMapping.class.getName() + ".producibleMediaTypes"; 085 086 087 /** 088 * Return a handler for this request. 089 * @param exchange current server exchange 090 * @return a {@link Mono} that emits one value or none in case the request 091 * cannot be resolved to a handler 092 */ 093 Mono<Object> getHandler(ServerWebExchange exchange); 094 095}