/**
* This file Copyright (c) 2010-2012 Magnolia International
* Ltd. (http://www.magnolia-cms.com). All rights reserved.
*
*
* This file is dual-licensed under both the Magnolia
* Network Agreement and the GNU General Public License.
* You may elect to use one or the other of these licenses.
*
* This file is distributed in the hope that it will be
* useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
* Redistribution, except as permitted by whichever of the GPL
* or MNA you select, is prohibited.
*
* 1. For the GPL license (GPL), you can redistribute and/or
* modify this file under the terms of the GNU General
* Public License, Version 3, as published by the Free Software
* Foundation. You should have received a copy of the GNU
* General Public License, Version 3 along with this program;
* if not, write to the Free Software Foundation, Inc., 51
* Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 2. For the Magnolia Network Agreement (MNA), this file
* and the accompanying materials are made available under the
* terms of the MNA which accompanies this distribution, and
* is available at http://www.magnolia-cms.com/mna.html
*
* Any modifications to this file must keep this entire header
* intact.
*
*/
package info.magnolia.rendering.model;
import info.magnolia.cms.core.AggregationState;
import info.magnolia.cms.core.Content;
import info.magnolia.cms.filters.OncePerRequestAbstractMgnlFilter;
import info.magnolia.cms.util.ContentUtil;
import info.magnolia.cms.util.RequestDispatchUtil;
import info.magnolia.context.MgnlContext;
import info.magnolia.jcr.util.NodeUtil;
import info.magnolia.registry.RegistrationException;
import info.magnolia.rendering.engine.RenderException;
import info.magnolia.rendering.renderer.Renderer;
import info.magnolia.rendering.renderer.RenderingModelBasedRenderer;
import info.magnolia.rendering.renderer.registry.RendererRegistry;
import info.magnolia.rendering.template.RenderableDefinition;
import info.magnolia.rendering.template.TemplateDefinition;
import info.magnolia.rendering.template.assignment.TemplateDefinitionAssignment;
import java.io.IOException;
import javax.inject.Inject;
import javax.jcr.Node;
import javax.jcr.RepositoryException;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Filter that executes the model for a renderable before template rendering. Looks for a request parameter containing
* the identifier of the renderable to execute. The model can decide to send output by itself in which case page rendering
* is skipped. The model can also return a URI prefixed by "redirect:", "permanent:" or "forward:" to trigger either
* a temporary redirect, a permanent redirect or a forward respectively. For redirects the URI can be absolute or
* relative within the web application (the context path is added automatically).
* <p/>
* By implementing the {@link EarlyExecutionAware} interface the callback will instead be made to a dedicated method
* making it easier to separate functionality for the two scenarios.
* <p/>
* To provide proper semantics this class mirrors functionality in RenderingEngine and AbstractRender, specifically in
* how it sets up the current content in aggregation state and creation and execution of the model.
*
* @version $Id$
* @see info.magnolia.rendering.renderer.AbstractRenderer
* @see info.magnolia.cms.util.RequestDispatchUtil
* @see EarlyExecutionAware
*/
public class ModelExecutionFilter extends OncePerRequestAbstractMgnlFilter {
public static final String MODEL_ATTRIBUTE_PREFIX = ModelExecutionFilter.class.getName() + "-model-";
public static final String ACTION_RESULT_ATTRIBUTE_PREFIX = ModelExecutionFilter.class.getName() + "-actionResult-";
public static final String DEFAULT_MODEL_EXECUTION_ATTRIBUTE_NAME = "mgnlModelExecutionUUID";
@Inject
private RendererRegistry rendererRegistry;
@Inject
private TemplateDefinitionAssignment templateDefinitionAssignment;
private String attributeName = DEFAULT_MODEL_EXECUTION_ATTRIBUTE_NAME;
public void setAttributeName(String attributeName) {
this.attributeName = attributeName;
}
@Override
public void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException {
String nodeIdentifier = getIdentifierOfNodeToExecute();
if (nodeIdentifier == null) {
chain.doFilter(request, response);
return;
}
Content content = ContentUtil.asContent(getContent(nodeIdentifier));
Content orgMainContent = null;
Content orgCurrentContent = null;
AggregationState state = getAggregationStateSafely();
if (state != null) {
orgMainContent = state.getMainContent();
orgCurrentContent = state.getCurrentContent();
state.setCurrentContent(content);
// if not yet set the passed content is the entry point of the rendering
if (orgMainContent == null) {
state.setMainContent(content);
}
}
try {
TemplateDefinition templateDefinition = getTemplateDefinition(content.getJCRNode());
RenderingModelBasedRenderer renderingModelBasedRenderer = getRenderingModelBasedRenderer(templateDefinition);
RenderingModel renderingModel;
try {
renderingModel = renderingModelBasedRenderer.newModel(content.getJCRNode(), templateDefinition, null);
}
catch (RenderException e) {
throw new ServletException(e.getMessage(), e);
}
String actionResult;
if (renderingModel instanceof EarlyExecutionAware) {
actionResult = ((EarlyExecutionAware)renderingModel).executeEarly();
} else {
actionResult = renderingModel.execute();
}
if (handleExecutionResult(renderingModel, actionResult, templateDefinition, request, response)) {
return;
}
// Proceed with page rendering, the model will be reused later when the renderable is rendered.
MgnlContext.setAttribute(MODEL_ATTRIBUTE_PREFIX + nodeIdentifier, renderingModel);
MgnlContext.setAttribute(ACTION_RESULT_ATTRIBUTE_PREFIX + nodeIdentifier, actionResult);
try {
chain.doFilter(request, response);
} finally {
MgnlContext.removeAttribute(MODEL_ATTRIBUTE_PREFIX + nodeIdentifier);
MgnlContext.removeAttribute(ACTION_RESULT_ATTRIBUTE_PREFIX + nodeIdentifier);
}
} finally {
if (state != null) {
state.setMainContent(orgMainContent);
state.setCurrentContent(orgCurrentContent);
}
}
}
protected static AggregationState getAggregationStateSafely() {
if (MgnlContext.isWebContext()) {
return MgnlContext.getAggregationState();
}
return null;
}
protected String getIdentifierOfNodeToExecute() {
return (String) MgnlContext.getInstance().getAttribute(attributeName);
}
/**
* Returns the content node for the supplied node identifier. Never returns null.
*/
protected Node getContent(String nodeIdentifier) throws ServletException {
String workspace = MgnlContext.getAggregationState().getRepository();
try {
return MgnlContext.getJCRSession(workspace).getNodeByIdentifier(nodeIdentifier);
} catch (RepositoryException e) {
throw new ServletException("Can't read content for early execution, node: " + nodeIdentifier, e);
}
}
/**
* Returns the TemplateDefinition for the supplied content. Never returns null.
*/
protected TemplateDefinition getTemplateDefinition(Node content) throws ServletException {
TemplateDefinition templateDefinition;
try {
templateDefinition = templateDefinitionAssignment.getAssignedTemplateDefinition(content);
} catch (RegistrationException e) {
throw new ServletException("No template set or template not available for node with identifier: " + NodeUtil.getNodeIdentifierIfPossible(content));
}
if (templateDefinition == null) {
throw new ServletException("Template not available for node with identifier: " + NodeUtil.getNodeIdentifierIfPossible(content));
}
return templateDefinition;
}
/**
* Returns the Renderer for the supplied renderable if it supports RenderingModel. Never returns null.
* @throws IllegalArgumentException if there is no renderer registered for the renderable
* @throws ServletException if the renderer does not support RenderingModel
*/
protected RenderingModelBasedRenderer getRenderingModelBasedRenderer(RenderableDefinition renderableDefinition) throws ServletException {
Renderer renderer;
try {
renderer = rendererRegistry.getRenderer(renderableDefinition.getRenderType());
} catch (RegistrationException e) {
throw new ServletException(e);
}
if (!(renderer instanceof RenderingModelBasedRenderer)) {
throw new ServletException("Renderer [" + renderableDefinition.getRenderType() + "] does not support RenderingModel");
}
return (RenderingModelBasedRenderer) renderer;
}
protected boolean handleExecutionResult(RenderingModel renderingModel, String actionResult, TemplateDefinition templateDefinition, HttpServletRequest request, HttpServletResponse response) {
// If the model rendered something on its own or sent a redirect we will not proceed with rendering.
if (response.isCommitted()) {
return false;
}
if (actionResult == null) {
return false;
}
if (actionResult.equals(RenderingModel.SKIP_RENDERING)) {
return true;
}
if (RequestDispatchUtil.dispatch(actionResult, request, response)) {
return true;
}
return false;
}
}