/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. The ASF licenses this file to You
* under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License. For additional information regarding
* copyright in this work, please see the NOTICE file in the top level
* directory of this distribution.
*/
package org.apache.roller.ui.rendering.servlets;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.JspFactory;
import javax.servlet.jsp.PageContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.roller.RollerException;
import org.apache.roller.config.RollerConfig;
import org.apache.roller.config.RollerRuntimeConfig;
import org.apache.roller.pojos.Template;
import org.apache.roller.pojos.Theme;
import org.apache.roller.pojos.WebsiteData;
import org.apache.roller.ui.core.RollerContext;
import org.apache.roller.util.cache.CachedContent;
import org.apache.roller.ui.rendering.Renderer;
import org.apache.roller.ui.rendering.RendererManager;
import org.apache.roller.ui.rendering.model.ModelLoader;
import org.apache.roller.ui.rendering.util.WeblogPreviewRequest;
/**
* Responsible for rendering weblog page previews.
*
* This servlet is used as part of the authoring interface to provide previews
* of what a weblog will look like with a given theme. It is not available
* outside of the authoring interface.
*
* @web.servlet name="PreviewServlet" load-on-startup="9"
* @web.servlet-mapping url-pattern="/roller-ui/authoring/preview/*"
*/
public class PreviewServlet extends HttpServlet {
private static Log log = LogFactory.getLog(PreviewServlet.class);
/**
* Init method for this servlet
*/
public void init(ServletConfig servletConfig) throws ServletException {
super.init(servletConfig);
log.info("Initializing PreviewServlet");
}
/**
* Handle GET requests for weblog pages.
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
log.debug("Entering");
WebsiteData weblog = null;
WeblogPreviewRequest previewRequest = null;
try {
previewRequest = new WeblogPreviewRequest(request);
// lookup weblog specified by preview request
weblog = previewRequest.getWeblog();
if(weblog == null) {
throw new RollerException("unable to lookup weblog: "+
previewRequest.getWeblogHandle());
}
} catch (Exception e) {
// some kind of error parsing the request or getting weblog
log.error("error creating preview request", e);
response.sendError(HttpServletResponse.SC_NOT_FOUND);
return;
}
// try getting the preview theme
log.debug("preview theme = "+previewRequest.getThemeName());
Theme previewTheme = previewRequest.getTheme();
// construct a temporary Website object for this request
// and set the EditorTheme to our previewTheme
WebsiteData tmpWebsite = new WebsiteData();
tmpWebsite.setData(weblog);
if(previewTheme != null && previewTheme.isEnabled()) {
tmpWebsite.setEditorTheme(previewTheme.getName());
} else if(Theme.CUSTOM.equals(previewRequest.getThemeName())) {
tmpWebsite.setEditorTheme(Theme.CUSTOM);
}
// we've got to set the weblog in our previewRequest because that's
// the object that gets referenced during rendering operations
previewRequest.setWeblog(tmpWebsite);
Template page = null;
try {
// we just want to show the default view
page = tmpWebsite.getDefaultPage();
if(page == null) {
throw new RollerException("No default page for weblog: "+tmpWebsite.getHandle());
}
} catch(RollerException re) {
// couldn't get page
response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
log.error("Error getting default page for preview", re);
return;
}
log.debug("preview page found, dealing with it");
// set the content type
String pageLink = previewRequest.getWeblogPageName();
String mimeType = pageLink != null ? RollerContext.getServletContext().getMimeType(pageLink) : null;
String contentType = "text/html; charset=utf-8";
if(mimeType != null) {
// we found a match ... set the content type
contentType = mimeType+"; charset=utf-8";
} else if ("_css".equals(previewRequest.getWeblogPageName())) {
// TODO: store content-type for each page so this hack is unnecessary
contentType = "text/css; charset=utf-8";
}
// looks like we need to render content
Map model = new HashMap();
try {
PageContext pageContext = JspFactory.getDefaultFactory().getPageContext(
this, request, response,"", false, 8192, true);
// special hack for menu tag
request.setAttribute("pageRequest", previewRequest);
// populate the rendering model
Map initData = new HashMap();
initData.put("request", request);
initData.put("weblogRequest", previewRequest);
initData.put("pageContext", pageContext);
// Load models for page previewing
String pageModels = RollerConfig.getProperty("rendering.previewModels");
ModelLoader.loadModels(pageModels, model, initData, true);
// Load special models for site-wide blog
if(RollerRuntimeConfig.isSiteWideWeblog(weblog.getHandle())) {
String siteModels = RollerConfig.getProperty("rendering.siteModels");
ModelLoader.loadModels(siteModels, model, initData, true);
}
// Load weblog custom models
ModelLoader.loadCustomModels(weblog, model, initData);
// ick, gotta load pre-3.0 model stuff as well :(
ModelLoader.loadOldModels(model, request, response, pageContext, previewRequest);
} catch (RollerException ex) {
log.error("ERROR loading model for page", ex);
if(!response.isCommitted()) response.reset();
response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
return;
}
// lookup Renderer we are going to use
Renderer renderer = null;
try {
log.debug("Looking up renderer");
renderer = RendererManager.getRenderer(page);
} catch(Exception e) {
// nobody wants to render my content :(
log.error("Couldn't find renderer for page "+page.getId(), e);
if(!response.isCommitted()) response.reset();
response.sendError(HttpServletResponse.SC_NOT_FOUND);
return;
}
// render content. use default size of about 24K for a standard page
CachedContent rendererOutput = new CachedContent(24567);
try {
log.debug("Doing rendering");
renderer.render(model, rendererOutput.getCachedWriter());
// flush rendered output and close
rendererOutput.flush();
rendererOutput.close();
} catch(Exception e) {
// bummer, error during rendering
log.error("Error during rendering for page "+page.getId(), e);
if(!response.isCommitted()) response.reset();
response.sendError(HttpServletResponse.SC_NOT_FOUND);
return;
}
// post rendering process
// flush rendered content to response
log.debug("Flushing response output");
response.setContentType(contentType);
response.setContentLength(rendererOutput.getContent().length);
response.getOutputStream().write(rendererOutput.getContent());
log.debug("Exiting");
}
}