/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. 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.
*/
package org.apache.shindig.gadgets.render;
import org.apache.shindig.common.uri.Uri;
import org.apache.shindig.config.ContainerConfig;
import org.apache.shindig.gadgets.Gadget;
import org.apache.shindig.gadgets.GadgetContext;
import org.apache.shindig.gadgets.GadgetException;
import org.apache.shindig.gadgets.LockedDomainService;
import org.apache.shindig.gadgets.process.ProcessingException;
import org.apache.shindig.gadgets.process.Processor;
import org.apache.shindig.gadgets.spec.View;
import com.google.inject.Inject;
import java.util.List;
import java.util.logging.Logger;
import java.util.regex.Pattern;
/**
* Validates a rendering request parameters before calling an appropriate renderer.
*/
public class Renderer {
private static final Logger LOG = Logger.getLogger(Renderer.class.getName());
private final Processor processor;
private final HtmlRenderer renderer;
private final ContainerConfig containerConfig;
private final LockedDomainService lockedDomainService;
@Inject
public Renderer(Processor processor,
HtmlRenderer renderer,
ContainerConfig containerConfig,
LockedDomainService lockedDomainService) {
this.processor = processor;
this.renderer = renderer;
this.containerConfig = containerConfig;
this.lockedDomainService = lockedDomainService;
}
/**
* Attempts to render the requested gadget.
*
* @return The results of the rendering attempt.
*
* TODO: Localize error messages.
*/
public RenderingResults render(GadgetContext context) {
if (!validateParent(context)) {
return RenderingResults.error("Unsupported parent parameter. Check your container code.");
}
try {
Gadget gadget = processor.process(context);
if (gadget.getCurrentView() == null) {
return RenderingResults.error("Unable to locate an appropriate view in this gadget. " +
"Requested: '" + gadget.getContext().getView() +
"' Available: " + gadget.getSpec().getViews().keySet());
}
if (gadget.getCurrentView().getType() == View.ContentType.URL) {
return RenderingResults.mustRedirect(gadget.getCurrentView().getHref());
}
if (!lockedDomainService.gadgetCanRender(context.getHost(), gadget, context.getContainer())) {
return RenderingResults.error("Invalid domain");
}
return RenderingResults.ok(renderer.render(gadget));
} catch (RenderingException e) {
return logError(context.getUrl(), e);
} catch (ProcessingException e) {
return logError(context.getUrl(), e);
} catch (RuntimeException e) {
if (e.getCause() instanceof GadgetException) {
return logError(context.getUrl(), e.getCause());
}
throw e;
}
}
private RenderingResults logError(Uri gadgetUrl, Throwable t) {
LOG.info("Failed to render gadget " + gadgetUrl + ": " + t.getMessage());
return RenderingResults.error(t.getMessage());
}
/**
* Validates that the parent parameter was acceptable.
*
* @return True if the parent parameter is valid for the current container.
*/
private boolean validateParent(GadgetContext context) {
String container = context.getContainer();
String parent = context.getParameter("parent");
if (parent == null) {
// If there is no parent parameter, we are still safe because no
// dependent code ever has to trust it anyway.
return true;
}
List<Object> parents = containerConfig.getList(container, "gadgets.parent");
if (parents.isEmpty()) {
// Allow all.
return true;
}
// We need to check each possible parent parameter against this regex.
for (Object pattern : parents) {
if (Pattern.matches(pattern.toString(), parent)) {
return true;
}
}
return false;
}
}