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.web.filter;
018
019import java.io.IOException;
020import java.io.InputStream;
021import java.nio.charset.Charset;
022import java.util.ArrayList;
023import java.util.Arrays;
024import java.util.Collections;
025import java.util.Enumeration;
026import java.util.LinkedHashMap;
027import java.util.LinkedHashSet;
028import java.util.List;
029import java.util.Map;
030import java.util.Set;
031import javax.servlet.FilterChain;
032import javax.servlet.ServletException;
033import javax.servlet.http.HttpServletRequest;
034import javax.servlet.http.HttpServletRequestWrapper;
035import javax.servlet.http.HttpServletResponse;
036
037import org.springframework.http.HttpInputMessage;
038import org.springframework.http.MediaType;
039import org.springframework.http.converter.FormHttpMessageConverter;
040import org.springframework.http.converter.support.AllEncompassingFormHttpMessageConverter;
041import org.springframework.http.server.ServletServerHttpRequest;
042import org.springframework.util.Assert;
043import org.springframework.util.LinkedMultiValueMap;
044import org.springframework.util.MultiValueMap;
045import org.springframework.util.StringUtils;
046
047/**
048 * {@link javax.servlet.Filter} that makes form encoded data available through
049 * the {@code ServletRequest.getParameter*()} family of methods during HTTP PUT
050 * or PATCH requests.
051 *
052 * <p>The Servlet spec requires form data to be available for HTTP POST but
053 * not for HTTP PUT or PATCH requests. This filter intercepts HTTP PUT and PATCH
054 * requests where content type is {@code 'application/x-www-form-urlencoded'},
055 * reads form encoded content from the body of the request, and wraps the ServletRequest
056 * in order to make the form data available as request parameters just like
057 * it is for HTTP POST requests.
058 *
059 * @author Rossen Stoyanchev
060 * @since 3.1
061 */
062public class HttpPutFormContentFilter extends OncePerRequestFilter {
063
064        private FormHttpMessageConverter formConverter = new AllEncompassingFormHttpMessageConverter();
065
066
067        /**
068         * Set the converter to use for parsing form content.
069         * <p>By default this is an instnace of {@link AllEncompassingFormHttpMessageConverter}.
070         */
071        public void setFormConverter(FormHttpMessageConverter converter) {
072                Assert.notNull(converter, "FormHttpMessageConverter is required.");
073                this.formConverter = converter;
074        }
075
076        public FormHttpMessageConverter getFormConverter() {
077                return this.formConverter;
078        }
079
080        /**
081         * The default character set to use for reading form data.
082         * This is a shortcut for:<br>
083         * {@code getFormConverter.setCharset(charset)}.
084         */
085        public void setCharset(Charset charset) {
086                this.formConverter.setCharset(charset);
087        }
088
089
090        @Override
091        protected void doFilterInternal(final HttpServletRequest request, HttpServletResponse response,
092                        FilterChain filterChain) throws ServletException, IOException {
093
094                if (("PUT".equals(request.getMethod()) || "PATCH".equals(request.getMethod())) && isFormContentType(request)) {
095                        HttpInputMessage inputMessage = new ServletServerHttpRequest(request) {
096                                @Override
097                                public InputStream getBody() throws IOException {
098                                        return request.getInputStream();
099                                }
100                        };
101                        MultiValueMap<String, String> formParameters = this.formConverter.read(null, inputMessage);
102                        if (!formParameters.isEmpty()) {
103                                HttpServletRequest wrapper = new HttpPutFormContentRequestWrapper(request, formParameters);
104                                filterChain.doFilter(wrapper, response);
105                                return;
106                        }
107                }
108
109                filterChain.doFilter(request, response);
110        }
111
112        private boolean isFormContentType(HttpServletRequest request) {
113                String contentType = request.getContentType();
114                if (contentType != null) {
115                        try {
116                                MediaType mediaType = MediaType.parseMediaType(contentType);
117                                return (MediaType.APPLICATION_FORM_URLENCODED.includes(mediaType));
118                        }
119                        catch (IllegalArgumentException ex) {
120                                return false;
121                        }
122                }
123                else {
124                        return false;
125                }
126        }
127
128
129        private static class HttpPutFormContentRequestWrapper extends HttpServletRequestWrapper {
130
131                private MultiValueMap<String, String> formParameters;
132
133                public HttpPutFormContentRequestWrapper(HttpServletRequest request, MultiValueMap<String, String> parameters) {
134                        super(request);
135                        this.formParameters = (parameters != null ? parameters : new LinkedMultiValueMap<String, String>());
136                }
137
138                @Override
139                public String getParameter(String name) {
140                        String queryStringValue = super.getParameter(name);
141                        String formValue = this.formParameters.getFirst(name);
142                        return (queryStringValue != null ? queryStringValue : formValue);
143                }
144
145                @Override
146                public Map<String, String[]> getParameterMap() {
147                        Map<String, String[]> result = new LinkedHashMap<String, String[]>();
148                        Enumeration<String> names = getParameterNames();
149                        while (names.hasMoreElements()) {
150                                String name = names.nextElement();
151                                result.put(name, getParameterValues(name));
152                        }
153                        return result;
154                }
155
156                @Override
157                public Enumeration<String> getParameterNames() {
158                        Set<String> names = new LinkedHashSet<String>();
159                        names.addAll(Collections.list(super.getParameterNames()));
160                        names.addAll(this.formParameters.keySet());
161                        return Collections.enumeration(names);
162                }
163
164                @Override
165                public String[] getParameterValues(String name) {
166                        String[] parameterValues = super.getParameterValues(name);
167                        List<String> formParam = this.formParameters.get(name);
168                        if (formParam == null) {
169                                return parameterValues;
170                        }
171                        if (parameterValues == null || getQueryString() == null) {
172                                return StringUtils.toStringArray(formParam);
173                        }
174                        else {
175                                List<String> result = new ArrayList<String>(parameterValues.length + formParam.size());
176                                result.addAll(Arrays.asList(parameterValues));
177                                result.addAll(formParam);
178                                return StringUtils.toStringArray(result);
179                        }
180                }
181        }
182
183}