001/* 002 * Copyright 2002-2018 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.http.server.reactive; 018 019import java.util.LinkedHashMap; 020import java.util.Map; 021 022import reactor.core.publisher.Mono; 023 024import org.springframework.http.HttpStatus; 025import org.springframework.util.Assert; 026 027/** 028 * {@code HttpHandler} delegating requests to one of several {@code HttpHandler}'s 029 * based on simple, prefix-based mappings. 030 * 031 * <p>This is intended as a coarse-grained mechanism for delegating requests to 032 * one of several applications -- each represented by an {@code HttpHandler}, with 033 * the application "context path" (the prefix-based mapping) exposed via 034 * {@link ServerHttpRequest#getPath()}. 035 * 036 * @author Rossen Stoyanchev 037 * @since 5.0 038 */ 039public class ContextPathCompositeHandler implements HttpHandler { 040 041 private final Map<String, HttpHandler> handlerMap; 042 043 044 public ContextPathCompositeHandler(Map<String, ? extends HttpHandler> handlerMap) { 045 Assert.notEmpty(handlerMap, "Handler map must not be empty"); 046 this.handlerMap = initHandlers(handlerMap); 047 } 048 049 private static Map<String, HttpHandler> initHandlers(Map<String, ? extends HttpHandler> map) { 050 map.keySet().forEach(ContextPathCompositeHandler::assertValidContextPath); 051 return new LinkedHashMap<>(map); 052 } 053 054 private static void assertValidContextPath(String contextPath) { 055 Assert.hasText(contextPath, "Context path must not be empty"); 056 if (contextPath.equals("/")) { 057 return; 058 } 059 Assert.isTrue(contextPath.startsWith("/"), "Context path must begin with '/'"); 060 Assert.isTrue(!contextPath.endsWith("/"), "Context path must not end with '/'"); 061 } 062 063 064 @Override 065 public Mono<Void> handle(ServerHttpRequest request, ServerHttpResponse response) { 066 // Remove underlying context path first (e.g. Servlet container) 067 String path = request.getPath().pathWithinApplication().value(); 068 return this.handlerMap.entrySet().stream() 069 .filter(entry -> path.startsWith(entry.getKey())) 070 .findFirst() 071 .map(entry -> { 072 String contextPath = request.getPath().contextPath().value() + entry.getKey(); 073 ServerHttpRequest newRequest = request.mutate().contextPath(contextPath).build(); 074 return entry.getValue().handle(newRequest, response); 075 }) 076 .orElseGet(() -> { 077 response.setStatusCode(HttpStatus.NOT_FOUND); 078 return response.setComplete(); 079 }); 080 } 081 082}