bakeweblogaction.java

这个weblogging 设计得比较精巧

package org.roller.presentation.weblog.actions;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts.action.ActionError;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.actions.DispatchAction;
import org.apache.velocity.VelocityContext;
import org.apache.velocity.app.Velocity;
import org.apache.velocity.exception.MethodInvocationException;
import org.apache.velocity.exception.ParseErrorException;
import org.apache.velocity.exception.ResourceNotFoundException;
import org.roller.RollerException;
import org.roller.model.UserManager;
import org.roller.model.WeblogManager;
import org.roller.pojos.PageData;
import org.roller.pojos.WebsiteData;
import org.roller.presentation.RollerContext;
import org.roller.presentation.RollerRequest;
import org.roller.presentation.RollerSession;
import org.roller.presentation.velocity.ContextLoader;
import org.roller.presentation.weblog.tags.WeblogEntryMacros;
import org.roller.util.DateUtil;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.StringWriter;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.JspFactory;
import javax.servlet.jsp.PageContext;

/////////////////////////////////////////////////////////////////////////////
/**
 * Generates static pages for each day containing Weblog entries.
 *
 * @struts.action name="bakeWeblogForm" path="/editor/bake"
 * 		scope="session" parameter="method"
 *
 * @struts.action-forward name="baking.done" path="/weblog/bakeWeblog.jsp"
 *
 * @author llavandowska
 */
public class BakeWeblogAction extends DispatchAction {
    private static Log mLogger =
            LogFactory.getFactory().getInstance(BakeWeblogAction.class);
    
    public ActionForward load(
            ActionMapping       mapping,
            ActionForm          actionForm,
            HttpServletRequest  request,
            HttpServletResponse response)
            throws IOException, ServletException {
        RollerRequest rreq = RollerRequest.getRollerRequest(request);
        try {
            if ( !rreq.isUserAuthorizedToEdit() ) {
                return mapping.findForward("access-denied");
            }
        } catch (Exception e) {
            return mapping.findForward("access-denied");
        }
        return mapping.findForward("baking.done");
    }
    
    public ActionForward bake(
            ActionMapping       mapping,
            ActionForm          actionForm,
            HttpServletRequest  request,
            HttpServletResponse response)
            throws IOException, ServletException {
        ActionForward forward = mapping.findForward("baking.done");
        ActionErrors errors = new ActionErrors();
        try {
            PageContext pageContext =
                    JspFactory.getDefaultFactory().getPageContext(
                    this.getServlet(), request, response,"", true, 8192, true);
            RollerRequest rreq = RollerRequest.getRollerRequest(pageContext);
            if ( !rreq.isUserAuthorizedToEdit() ) {
                return mapping.findForward("access-denied");
            }
            
            String pid = getDefaultPageId( rreq );
            
            VelocityContext context = new VelocityContext();
            ContextLoader.setupContext( context, rreq, response );
            
            // Get this months Entries
            WeblogManager mgr = rreq.getRoller().getWeblogManager();
            //Map entryMap = mgr.getWeblogEntryMonthMap(
            //rreq.getUser().getUserName(),
            //rreq.getDate(true),
            //null,
            //false,
            //true );
            
            Map entryMap = mgr.getWeblogEntryObjectMap(
                    rreq.getWebsite(),
                    null,                        // startDate
                    rreq.getDate(true),          // endDate
                    null,                        // catName
                    WeblogManager.PUB_ONLY,      // status
                    null);                      // maxEntries
            
            if (mLogger.isDebugEnabled()) {
                mLogger.debug("Num Days to Bake: " + entryMap.size());
            }
            
            Iterator iter = entryMap.keySet().iterator();
            if (iter.hasNext()) {
                Date d = (Date)iter.next();
                
                if (mLogger.isDebugEnabled()) {
                    mLogger.debug("Bake Weblog for date:" + d);
                }
                
                // Do we need this to continue supporting Macros?
                WeblogEntryMacros macros =
                        new WeblogEntryMacros( rreq.getPageContext(), d );
                context.put( "macros", macros );
                
                List entries = (List) entryMap.get( d );
                String content = transformTemplate(pid, entries, context, rreq);
                
                String fileName = writeToFile(content, d, rreq);
                request.getSession().setAttribute(
                        RollerSession.STATUS_MESSAGE,
                        "Weblog baked to :" + fileName);
            }
            
            /** put some user message **/
            String message = (String) request.getSession().getAttribute(
                    RollerSession.STATUS_MESSAGE);
            if (message == null) message = "No Files Written";
            request.getSession().setAttribute(
                    RollerSession.STATUS_MESSAGE,
                    message);
        } catch (Exception e) {
            forward = mapping.findForward("error");
            
            errors.add(ActionErrors.GLOBAL_ERROR,
                    new ActionError("error.bake.weblog", e.toString()));
            saveErrors(request,errors);
            
            mLogger.error(getResources(request).getMessage("error.bake.weblog")
            + e.toString(),e);
        }
        
        return forward;
    }
    
    /**
     * Write the content generated by transformTemplate to a file in the Upload
     * directory, where the user can reach it.
     *
     * @param content
     * @param d
     * @param rreq
     */
    private String writeToFile(String content, Date d, RollerRequest rreq)
    throws IOException {
        if (mLogger.isDebugEnabled()) {
            mLogger.debug("Write file for:" + d);
        }
        
        String dir = RollerContext.getUploadDir( rreq.getServletContext() );
        String username = rreq.getUser().getUserName();
        File dirF = new File(dir + username + File.separator + "baked");
        if (!dirF.exists()) {
            dirF.mkdirs();
        }
        
        SimpleDateFormat mFmt = DateUtil.get8charDateFormat();
        String dString = mFmt.format( d ) + ".html";
        File pFile = new File(dirF, dString);
        
        OutputStream bos = null;
        try {
            bos = new FileOutputStream(pFile);
            bos.write( content.getBytes() );
        } catch (IOException e) {
            mLogger.error("Unable to write to " + pFile.getName());
        } finally {
            try {
                if (bos != null) bos.close();
            } catch (IOException e1) {
                mLogger.error("Unable to close stream to " + pFile.getName());
            }
        }
        
        return pFile.getName();
    }
    
    /**
     * Transform the Page specified by the pageId using Velocity. Return the
     * resulting String.
     *
     * @param pid
     * @param context
     * @throws ResourceNotFoundException
     * @throws ParseErrorException
     * @throws MethodInvocationException
     * @throws Exception
     */
    private String transformTemplate(String pid, List entries,
            VelocityContext context, RollerRequest rreq)
            throws
            ResourceNotFoundException,
            ParseErrorException,
            MethodInvocationException,
            Exception {
        
        context.put( "entries", entries );
        
        StringWriter sw = new StringWriter();
        Velocity.mergeTemplate(pid, Velocity.ENCODING_DEFAULT, context, sw );
        return sw.toString();
    }
    
    /**
     * Get the default pageId for this Website, this is assumed to be the Weblog
     * page since we have no other way of declaring it.
     *
     * @param rreq
     * @return String
     * @throws RollerException
     */
    private String getDefaultPageId(RollerRequest rreq) throws RollerException {
        UserManager userMgr = rreq.getRoller().getUserManager();
        WebsiteData wd = rreq.getWebsite();
        PageData pd = userMgr.retrievePage(wd.getDefaultPageId());
        return pd.getId();
    }
    
}