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     */
019    
020    package org.apache.myfaces.tobago.ajax.api;
021    
022    import org.apache.commons.lang.StringUtils;
023    import org.apache.commons.logging.Log;
024    import org.apache.commons.logging.LogFactory;
025    import static org.apache.myfaces.tobago.TobagoConstants.ATTR_CHARSET;
026    import org.apache.myfaces.tobago.component.ComponentUtil;
027    import static org.apache.myfaces.tobago.lifecycle.TobagoLifecycle.FACES_MESSAGES_KEY;
028    import static org.apache.myfaces.tobago.lifecycle.TobagoLifecycle.VIEW_ROOT_KEY;
029    import org.apache.myfaces.tobago.renderkit.html.HtmlAttributes;
030    import org.apache.myfaces.tobago.renderkit.html.HtmlConstants;
031    import org.apache.myfaces.tobago.util.Callback;
032    import org.apache.myfaces.tobago.util.EncodeAjaxCallback;
033    import org.apache.myfaces.tobago.util.FastStringWriter;
034    import org.apache.myfaces.tobago.util.JndiUtils;
035    import org.apache.myfaces.tobago.util.RequestUtils;
036    import org.apache.myfaces.tobago.util.ResponseUtils;
037    
038    import javax.faces.FactoryFinder;
039    import javax.faces.application.StateManager;
040    import javax.faces.component.UIComponent;
041    import javax.faces.component.UIViewRoot;
042    import javax.faces.context.ExternalContext;
043    import javax.faces.context.FacesContext;
044    import javax.faces.context.ResponseWriter;
045    import javax.faces.render.RenderKit;
046    import javax.faces.render.RenderKitFactory;
047    import javax.naming.InitialContext;
048    import javax.naming.NamingException;
049    import javax.servlet.http.HttpServletResponse;
050    import java.io.IOException;
051    import java.io.PrintWriter;
052    import java.util.ArrayList;
053    import java.util.Collections;
054    import java.util.EmptyStackException;
055    import java.util.Iterator;
056    import java.util.List;
057    import java.util.Map;
058    
059    public class AjaxResponseRenderer {
060    
061      private static final Log LOG = LogFactory.getLog(AjaxResponseRenderer.class);
062    
063      public static final String CODE_SUCCESS = "<status code=\"200\"/>";
064      public static final String CODE_NOT_MODIFIED = "<status code=\"304\"/>";
065      public static final String CODE_RELOAD_REQUIRED = "<status code=\"309\"/>";
066    
067      private Callback callback;
068      private String contentType;
069    
070      public AjaxResponseRenderer() {
071        callback = new EncodeAjaxCallback();
072        try {
073          InitialContext ic = new InitialContext();
074          contentType = (String) JndiUtils.getJndiProperty(ic, "tobago.ajax.contentType");
075        } catch (NamingException e) { /*ignore*/ }
076    
077        if (StringUtils.isBlank(contentType)) {
078          contentType = "text/html";
079        }
080      }
081    
082      public void renderResponse(FacesContext facesContext) throws IOException {
083        final UIViewRoot viewRoot = facesContext.getViewRoot();
084        RenderKitFactory renderFactory = (RenderKitFactory)
085            FactoryFinder.getFactory(FactoryFinder.RENDER_KIT_FACTORY);
086        RenderKit renderKit = renderFactory.getRenderKit(
087            facesContext, viewRoot.getRenderKitId());
088    
089        UIViewRoot incommingViewRoot = (UIViewRoot)
090            facesContext.getExternalContext().getRequestMap().get(VIEW_ROOT_KEY);
091        if (viewRoot != incommingViewRoot) {
092          if (LOG.isDebugEnabled()) {
093            LOG.debug("requesting full page reload because of navigation to "
094                + viewRoot.getViewId() + " from " + incommingViewRoot.getViewId());
095          }
096          Map sessionMap = facesContext.getExternalContext().getSessionMap();
097          //noinspection unchecked
098          sessionMap.put(VIEW_ROOT_KEY, viewRoot);
099          List<Object[]> messageHolders = new ArrayList<Object[]>();
100          Iterator clientIds = facesContext.getClientIdsWithMessages();
101          while (clientIds.hasNext()) {
102            String clientId = (String) clientIds.next();
103            Iterator messages = facesContext.getMessages(clientId);
104            while (messages.hasNext()) {
105              Object[] messageHolder = new Object[2];
106              messageHolder[0] = clientId;
107              messageHolder[1] = messages.next();
108              messageHolders.add(messageHolder);
109            }
110          }
111          if (!messageHolders.isEmpty()) {
112            //noinspection unchecked
113            sessionMap.put(FACES_MESSAGES_KEY, messageHolders);
114          }
115          writeResponseReload(facesContext, renderKit);
116        } else {
117          List<FastStringWriter> responseParts = new ArrayList<FastStringWriter>();
118          Map<String, UIComponent> ajaxComponents = AjaxUtils.getAjaxComponents(facesContext);
119    
120          for (Map.Entry<String, UIComponent> entry : ajaxComponents.entrySet()) {
121            AjaxComponent component = (AjaxComponent) entry.getValue();
122            responseParts.add(renderComponent(facesContext, renderKit, entry.getKey(), component));
123            break;  // TODO render multiple components
124          }
125    
126          String state = saveState(facesContext, renderKit);
127          writeResponse(facesContext, renderKit, responseParts, state);
128        }
129      }
130    
131      private FastStringWriter renderComponent(FacesContext facesContext, RenderKit renderKit, String clientId,
132          AjaxComponent component) throws IOException {
133        FastStringWriter content = new FastStringWriter();
134        ResponseWriter contentWriter = renderKit.createResponseWriter(content, null, null);
135        facesContext.setResponseWriter(contentWriter);
136        if (LOG.isDebugEnabled()) {
137          LOG.debug("write ajax response for " + component);
138        }
139    
140        try {
141          // TODO: invokeOnComponent()
142          ComponentUtil.invokeOnComponent(facesContext, clientId, (UIComponent) component, callback);
143        } catch (EmptyStackException e) {
144          LOG.error(" content = \"" + content.toString() + "\"");
145          throw e;
146        }
147    
148        return content;
149      }
150    
151      private void writeResponse(FacesContext facesContext, RenderKit renderKit,
152          List<FastStringWriter> parts, String state)
153          throws IOException {
154        writeResponse(facesContext, renderKit, CODE_SUCCESS, parts, state);
155      }
156    
157      private void writeResponseReload(FacesContext facesContext, RenderKit renderKit)
158          throws IOException {
159        writeResponse(facesContext, renderKit, CODE_RELOAD_REQUIRED, Collections.EMPTY_LIST, "");
160      }
161    
162    
163      private FastStringWriter writeState(FacesContext facesContext, RenderKit renderKit, String state)
164          throws IOException {
165        FastStringWriter jsfState = new FastStringWriter();
166        ResponseWriter stateWriter = renderKit.createResponseWriter(jsfState, null, null);
167        facesContext.setResponseWriter(stateWriter);
168        stateWriter.startElement(HtmlConstants.SCRIPT, null);
169        stateWriter.writeAttribute(HtmlAttributes.TYPE, "text/javascript", null);
170        stateWriter.flush();
171        stateWriter.write("Tobago.replaceJsfState(\"");
172        stateWriter.write(encodeState(state));
173        stateWriter.write("\");");
174        stateWriter.endElement(HtmlConstants.SCRIPT);
175        return jsfState;
176      }
177    
178      private String saveState(FacesContext facesContext, RenderKit renderKit)
179          throws IOException {
180        FastStringWriter jsfState = new FastStringWriter();
181        ResponseWriter stateWriter = renderKit.createResponseWriter(jsfState, null, null);
182        facesContext.setResponseWriter(stateWriter);
183    
184        StateManager stateManager = facesContext.getApplication().getStateManager();
185        StateManager.SerializedView serializedView
186            = stateManager.saveSerializedView(facesContext);
187        stateManager.writeState(facesContext, serializedView);
188        return jsfState.toString();
189      }
190    
191      private static void ensureContentTypeHeader(FacesContext facesContext, String charset, String contentType) {
192        StringBuilder sb = new StringBuilder(contentType);
193        if (charset == null) {
194          charset = "UTF-8";
195        }
196        sb.append("; charset=");
197        sb.append(charset);
198        ResponseUtils.ensureContentTypeHeader(facesContext, sb.toString());
199    
200      }
201    
202      private void writeResponse(FacesContext facesContext, RenderKit renderKit,
203          String responseCode, List<FastStringWriter> responseParts, String jsfState)
204          throws IOException {
205        RequestUtils.ensureEncoding(facesContext);
206        ResponseUtils.ensureNoCacheHeader(facesContext);
207        UIComponent page = ComponentUtil.findPage(facesContext);
208        String charset;
209        if (page != null) {  // in case of CODE_RELOAD_REQUIRED page is null
210          charset = (String) page.getAttributes().get(ATTR_CHARSET);
211        } else {
212          charset = "UTF-8";
213        }
214        ensureContentTypeHeader(facesContext, charset, contentType);
215        StringBuilder buffer = new StringBuilder(responseCode);
216    
217        // add parts to response
218        for (FastStringWriter part : responseParts) {
219          // TODO surround by javascript parsable tokens
220          String partStr = part.toString();
221          // FIXME:
222          if (partStr.startsWith(responseCode)
223              || partStr.equals(CODE_NOT_MODIFIED)) {
224            // remove responseCode from buffer
225            buffer.setLength(0);
226          }
227          // FIXME:
228    
229          buffer.append(partStr);
230        }
231    
232        // add jsfState to response
233        if (jsfState.length() > 0) {
234          // in case of inputSuggest jsfState.lenght is 0
235          // inputSuggest is a special case, because the form is not included in request.
236          // TODO surround by javascript parsable token
237          buffer.append(writeState(facesContext, renderKit, jsfState));
238        }
239    
240        if (LOG.isTraceEnabled()) {
241          LOG.trace("\nresponse follows ##############################################################\n"
242              + buffer
243              + "\nend response    ##############################################################");
244        }
245    
246    
247        ExternalContext externalContext = facesContext.getExternalContext();
248        //TODO: fix this to work in PortletRequest as well
249        if (externalContext.getResponse() instanceof HttpServletResponse) {
250          final HttpServletResponse httpServletResponse
251              = (HttpServletResponse) externalContext.getResponse();
252          PrintWriter responseWriter = httpServletResponse.getWriter();
253          // buf.delete(buf.indexOf("<"), buf.indexOf(">")+1);
254          responseWriter.print(buffer.toString());
255          responseWriter.flush();
256          responseWriter.close();
257        }
258      }
259    
260      private String encodeState(String state) {
261        state = StringUtils.replace(state, "\"", "\\\"");
262        return StringUtils.replace(state, "\n", "");
263      }
264    }