UIServlet.java

/*
 * This program is free software; you can redistribute it and/or modify it under the 
 * terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software 
 * Foundation.
 *
 * You should have received a copy of the GNU Lesser General Public License along with this 
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html 
 * or from the Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Lesser General Public License for more details.
 *
 * Copyright 2005 - 2009 Pentaho Corporation.  All rights reserved.
 *
 *
 * @created Jul 22, 2005 
 * @author James Dixon
 * 
 */

package org.pentaho.platform.web.servlet;

import java.io.IOException;
import java.io.OutputStream;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.pentaho.platform.api.engine.IMessageFormatter;
import org.pentaho.platform.api.engine.IPentahoSession;
import org.pentaho.platform.api.ui.IUIComponent;
import org.pentaho.platform.engine.core.system.PentahoSystem;
import org.pentaho.platform.util.messages.LocaleHelper;
import org.pentaho.platform.util.web.SimpleUrlFactory;
import org.pentaho.platform.web.http.HttpOutputHandler;
import org.pentaho.platform.web.servlet.messages.Messages;

/**
 * @author James Dixon
 * 
 * TODO To change the template for this generated type comment go to Window -
 * Preferences - Java - Code Style - Code Templates
 */
public class UIServlet extends ServletBase {

  /**
   * 
   */
  private static final long serialVersionUID = 7018489258697145705L;

  private static final Log logger = LogFactory.getLog(UIServlet.class);

  @Override
  public Log getLogger() {
    return UIServlet.logger;
  }

  @Override
  protected void doGet(final HttpServletRequest request, final HttpServletResponse response) throws ServletException, IOException {
    PentahoSystem.systemEntryPoint();
    try {
    OutputStream outputStream = response.getOutputStream();

    String path = request.getContextPath();

    IPentahoSession userSession = getPentahoSession(request);
    HttpSession session = request.getSession();

    String user = request.getRemoteUser();

    if ((user != null) && !userSession.isAuthenticated()) {
      // the user was not logged in before but is now....
      userSession.setAuthenticated(user);
    }

    String type = request.getParameter("type"); //$NON-NLS-1$
    if (type == null) {
      type = "text/html"; //$NON-NLS-1$
    }

    // find out which component is going to fulfill this request
    String componentName = request.getParameter("component"); //$NON-NLS-1$
    if (componentName == null) {
      response.setContentType("text/html"); //$NON-NLS-1$
      StringBuffer buffer = new StringBuffer();
      PentahoSystem.get(IMessageFormatter.class, userSession)
          .formatErrorMessage(
              "text/html", Messages.getInstance().getString("UIServlet.ACTION_FAILED"), Messages.getInstance().getErrorString("UIServlet.ERROR_0001_COMPONENT_NOT_SPECIFIED"), buffer); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
      outputStream.write(buffer.toString().getBytes(LocaleHelper.getSystemEncoding()));
      return;

    }
    response.setCharacterEncoding(LocaleHelper.getSystemEncoding());
    // TODO switch this to the interface once stable
    IUIComponent component = (IUIComponent) session.getAttribute(componentName);
    if (component == null) {
      component = getComponent(componentName);
      if (component == null) {
        response.setContentType("text/html"); //$NON-NLS-1$
        StringBuffer buffer = new StringBuffer();
        PentahoSystem.get(IMessageFormatter.class, userSession)
            .formatErrorMessage(
                "text/html", Messages.getInstance().getString("UIServlet.ACTION_FAILED"), Messages.getInstance().getErrorString("UIServlet.ERROR_0002_COMPONENT_INVALID"), buffer); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
        outputStream.write(buffer.toString().getBytes(LocaleHelper.getSystemEncoding()));
        return;
      }
      session.setAttribute(componentName, component);
    }

    if (!component.validate()) {
      // TODO need an error here
      return;
    }
    String baseUrl = request.getScheme()
        + "://" + request.getServerName() + ":" + request.getServerPort() + path + "/content?type=" + type + "&component=" + componentName + "&"; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$ //$NON-NLS-5$

    response.setContentType(type);
    HttpOutputHandler outputHandler = new HttpOutputHandler(response, outputStream, true);

    SimpleUrlFactory urlFactory = new SimpleUrlFactory(baseUrl);

    HttpServletRequestHandler requestHandler = new HttpServletRequestHandler(userSession, null, request, outputHandler,
        urlFactory);

    requestHandler.handleUIRequest(component, type);
    } finally {
      PentahoSystem.systemExitPoint();
    }
  }

  private IUIComponent getComponent(final String componentName) {
    return (IUIComponent) PentahoSystem.createObject(componentName, this);
  }

  @Override
  protected void doPost(final HttpServletRequest request, final HttpServletResponse response) throws ServletException, IOException {

    doGet(request, response);

  }

}