001/* 002 * Copyright 2002-2017 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.socket.server.support; 018 019import java.util.Collections; 020import java.util.List; 021import java.util.Map; 022 023import org.apache.commons.logging.Log; 024import org.apache.commons.logging.LogFactory; 025 026import org.springframework.http.server.ServerHttpRequest; 027import org.springframework.http.server.ServerHttpResponse; 028import org.springframework.lang.Nullable; 029import org.springframework.web.socket.WebSocketHandler; 030import org.springframework.web.socket.server.HandshakeInterceptor; 031 032/** 033 * A helper class that assists with invoking a list of handshake interceptors. 034 * 035 * @author Rossen Stoyanchev 036 * @since 4.0 037 */ 038public class HandshakeInterceptorChain { 039 040 private static final Log logger = LogFactory.getLog(HandshakeInterceptorChain.class); 041 042 private final List<HandshakeInterceptor> interceptors; 043 044 private final WebSocketHandler wsHandler; 045 046 private int interceptorIndex = -1; 047 048 049 public HandshakeInterceptorChain(@Nullable List<HandshakeInterceptor> interceptors, WebSocketHandler wsHandler) { 050 this.interceptors = (interceptors != null ? interceptors : Collections.emptyList()); 051 this.wsHandler = wsHandler; 052 } 053 054 055 public boolean applyBeforeHandshake(ServerHttpRequest request, ServerHttpResponse response, 056 Map<String, Object> attributes) throws Exception { 057 058 for (int i = 0; i < this.interceptors.size(); i++) { 059 HandshakeInterceptor interceptor = this.interceptors.get(i); 060 if (!interceptor.beforeHandshake(request, response, this.wsHandler, attributes)) { 061 if (logger.isDebugEnabled()) { 062 logger.debug(interceptor + " returns false from beforeHandshake - precluding handshake"); 063 } 064 applyAfterHandshake(request, response, null); 065 return false; 066 } 067 this.interceptorIndex = i; 068 } 069 return true; 070 } 071 072 public void applyAfterHandshake( 073 ServerHttpRequest request, ServerHttpResponse response, @Nullable Exception failure) { 074 075 for (int i = this.interceptorIndex; i >= 0; i--) { 076 HandshakeInterceptor interceptor = this.interceptors.get(i); 077 try { 078 interceptor.afterHandshake(request, response, this.wsHandler, failure); 079 } 080 catch (Exception ex) { 081 if (logger.isWarnEnabled()) { 082 logger.warn(interceptor + " threw exception in afterHandshake: " + ex); 083 } 084 } 085 } 086 } 087 088}