/* ZumlExtendlet.java
Purpose:
Description:
History:
Wed Jul 4 17:35:14 2007, Created by tomyeh
Copyright (C) 2007 Potix Corporation. All Rights Reserved.
{{IS_RIGHT
This program is distributed under LGPL Version 2.1 in the hope that
it will be useful, but WITHOUT ANY WARRANTY.
}}IS_RIGHT
*/
package org.zkoss.zk.ui.http;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.StringWriter;
import java.io.Writer;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.zkoss.lang.Exceptions;
import org.zkoss.util.resource.ResourceCache;
import org.zkoss.web.servlet.Servlets;
import org.zkoss.web.servlet.http.Https;
import org.zkoss.web.util.resource.Extendlet;
import org.zkoss.web.util.resource.ExtendletConfig;
import org.zkoss.web.util.resource.ExtendletContext;
import org.zkoss.web.util.resource.ExtendletLoader;
import org.zkoss.zk.ui.Desktop;
import org.zkoss.zk.ui.Execution;
import org.zkoss.zk.ui.Page;
import org.zkoss.zk.ui.Session;
import org.zkoss.zk.ui.WebApp;
import org.zkoss.zk.ui.impl.RequestInfoImpl;
import org.zkoss.zk.ui.metainfo.PageDefinition;
import org.zkoss.zk.ui.metainfo.PageDefinitions;
import org.zkoss.zk.ui.sys.RequestInfo;
import org.zkoss.zk.ui.sys.WebAppCtrl;
/**
* The ZUML resource processor used to parse the ZUML files
* loaded from the classpath.
*
* @author tomyeh
* @since 2.4.1 (public since 5.0.5)
*/
public class ZumlExtendlet implements Extendlet {
private static final Logger log = LoggerFactory.getLogger(ZumlExtendlet.class);
private ExtendletContext _webctx;
/** PageDefinition cache. */
private ResourceCache<String, PageDefinition> _cache;
private ServletContext getServletContext() {
return _webctx.getServletContext();
}
private WebManager getWebManager() {
return WebManager.getWebManager(getServletContext());
}
private WebApp getWebApp() {
return getWebManager().getWebApp();
}
//Extendlet//
public void init(ExtendletConfig config) {
_webctx = config.getExtendletContext();
final ZumlLoader loader = new ZumlLoader();
_cache = new ResourceCache<String, PageDefinition>(loader, 17);
_cache.setMaxSize(512);
_cache.setLifetime(60 * 60 * 1000); //1hr
final int checkPeriod = loader.getCheckPeriod();
_cache.setCheckPeriod(checkPeriod >= 0 ? checkPeriod : 60 * 60 * 1000); //1hr
config.addCompressExtension("zul");
}
public boolean getFeature(int feature) {
return false; //not support ALLOW_DIRECT_INCLUDE
}
public void service(HttpServletRequest request, HttpServletResponse response, String path)
throws ServletException, IOException {
final Session sess = WebManager.getSession(getServletContext(), request);
final PageDefinition pagedef = _cache.get(path);
if (pagedef == null) {
//FUTURE: support the error page (from Configuration)
handleError(sess, request, response, path, null);
return;
}
//mimic DHtmlLayoutServlet to process PageDefinition
final Object old = I18Ns.setup(sess, request, response,
sess.getWebApp().getConfiguration().getResponseCharset());
try {
process(sess, request, response, pagedef, path);
} catch (Throwable ex) {
handleError(sess, request, response, path, ex);
} finally {
I18Ns.cleanup(request, old);
}
}
//-- private --//
/**
* Process the request.
* @return false if the page is not found.
*/
private void process(Session sess, HttpServletRequest request, HttpServletResponse response, PageDefinition pagedef,
String path) throws ServletException, IOException {
final WebApp wapp = sess.getWebApp();
final WebAppCtrl wappc = (WebAppCtrl) wapp;
final Desktop desktop = getWebManager().getDesktop(sess, request, response, path, true);
if (desktop == null) //forward or redirect
return;
final RequestInfo ri = new RequestInfoImpl(wapp, sess, desktop, request,
PageDefinitions.getLocator(wapp, path));
final boolean compress = _webctx.shallCompress(request, "zul");
final Page page = WebManager.newPage(wappc.getUiFactory(), ri, pagedef, response, path);
final Execution exec = new ExecutionImpl(getServletContext(), request, response, desktop, page);
final Writer out = compress ? (Writer) new StringWriter() : response.getWriter();
wappc.getUiEngine().execNewPage(exec, pagedef, page, out);
if (compress) {
final String result = ((StringWriter) out).toString();
try {
final OutputStream os = response.getOutputStream();
//Call it first to ensure getWrite() is not called yet
byte[] data = result.getBytes("UTF-8");
if (data.length > 200) {
byte[] bs = Https.gzip(request, response, null, data);
if (bs != null)
data = bs; //yes, browser support compress
}
response.setContentLength(data.length);
os.write(data);
response.flushBuffer();
} catch (IllegalStateException ex) { //getWriter is called
response.getWriter().write(result);
}
}
}
/** Handles exception being thrown when rendering a page.
* @param err the exception being throw. If null, it means the page
* is not found.
*/
private void handleError(Session sess, HttpServletRequest request, HttpServletResponse response, String path,
Throwable err) throws ServletException, IOException {
Utils.resetOwner();
//Note: if not included, it is handled by Web container
if (err != null && Servlets.isIncluded(request)) {
//Bug 1802487 and 1714094
final String errpg = sess.getWebApp().getConfiguration().getErrorPage(sess.getDeviceType(), err);
if (errpg != null) {
try {
request.setAttribute("javax.servlet.error.message", Exceptions.getMessage(err));
request.setAttribute("javax.servlet.error.exception", err);
request.setAttribute("javax.servlet.error.exception_type", err.getClass());
request.setAttribute("javax.servlet.error.status_code", new Integer(500));
Servlets.forward(getServletContext(), request, response, errpg, null, 0);
return; //done
} catch (IOException ex) { //eat it (connection off)
} catch (Throwable ex) {
log.warn("Failed to load the error page: " + errpg, ex);
}
}
}
Utils.handleError(getServletContext(), request, response, path, err);
}
/** Helper class. */
private class ZumlLoader extends ExtendletLoader<PageDefinition> {
private ZumlLoader() {
}
//-- super --//
//-- super --//
protected PageDefinition parse(InputStream is, String path, String orgpath) throws Exception {
return PageDefinitions.getPageDefinitionDirectly(getWebApp(), _webctx.getLocator(),
new java.io.InputStreamReader(is, "UTF-8"), Servlets.getExtension(path));
}
protected ExtendletContext getExtendletContext() {
return _webctx;
}
}
}