001/*
002 *  Licensed to the Apache Software Foundation (ASF) under one
003 *  or more contributor license agreements.  See the NOTICE file
004 *  distributed with this work for additional information
005 *  regarding copyright ownership.  The ASF licenses this file
006 *  to you under the Apache License, Version 2.0 (the
007 *  "License"); you may not use this file except in compliance
008 *  with the License.  You may obtain a copy of the License at
009 *
010 *        http://www.apache.org/licenses/LICENSE-2.0
011 *
012 *  Unless required by applicable law or agreed to in writing,
013 *  software distributed under the License is distributed on an
014 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 *  KIND, either express or implied.  See the License for the
016 *  specific language governing permissions and limitations
017 *  under the License.
018 */
019package org.apache.isis.core.webapp.diagnostics;
020
021import java.io.IOException;
022
023import javax.servlet.Filter;
024import javax.servlet.FilterChain;
025import javax.servlet.FilterConfig;
026import javax.servlet.ServletException;
027import javax.servlet.ServletRequest;
028import javax.servlet.ServletResponse;
029import javax.servlet.http.HttpServletRequest;
030
031import org.slf4j.Logger;
032import org.slf4j.LoggerFactory;
033
034/**
035 * Simply logs the URL of any request that causes an exception to be thrown.
036 */
037public class IsisLogOnExceptionFilter implements Filter {
038
039    private static final Logger LOG = LoggerFactory.getLogger(IsisLogOnExceptionFilter.class);
040
041    @Override
042    public void init(FilterConfig filterConfig) throws ServletException {
043    }
044
045    @Override
046    public void destroy() {
047    }
048
049    @Override
050    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
051        try {
052            chain.doFilter(request, response);
053        } catch (IOException e) {
054            logRequestUrl(request, e);
055            throw e;
056        } catch (ServletException e) {
057            logRequestUrl(request, e);
058            throw e;
059        } catch (RuntimeException e) {
060            logRequestUrl(request, e);
061            throw e;
062        }
063    }
064
065    private static void logRequestUrl(ServletRequest request, Exception e) {
066        if(!(request instanceof HttpServletRequest)) {
067            return;
068        } 
069        final HttpServletRequest httpServletRequest = (HttpServletRequest) request;
070        final StringBuffer buf = httpServletRequest.getRequestURL();
071        final String queryString = httpServletRequest.getQueryString();
072        if(queryString != null) {
073            buf.append("?" + queryString);
074        }
075        
076        LOG.error("Request caused " + e.getClass().getName() + ": " + buf.toString());
077    }
078}