/*
* 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.UriBuilder;
import org.apache.shindig.gadgets.Gadget;
import org.apache.shindig.gadgets.GadgetContext;
import org.apache.shindig.gadgets.GadgetException;
import org.apache.shindig.gadgets.http.ContentFetcherFactory;
import org.apache.shindig.gadgets.http.HttpRequest;
import org.apache.shindig.gadgets.http.HttpResponse;
import org.apache.shindig.gadgets.oauth.OAuthArguments;
import org.apache.shindig.gadgets.preload.PreloaderService;
import org.apache.shindig.gadgets.preload.Preloads;
import org.apache.shindig.gadgets.rewrite.ContentRewriterRegistry;
import org.apache.shindig.gadgets.spec.GadgetSpec;
import org.apache.shindig.gadgets.spec.View;
import com.google.inject.Inject;
/**
* Handles producing output markup for a gadget based on the provided context.
*/
public class HtmlRenderer {
private final ContentFetcherFactory fetcher;
private final PreloaderService preloader;
private final ContentRewriterRegistry rewriter;
@Inject
public HtmlRenderer(ContentFetcherFactory fetcher,
PreloaderService preloader,
ContentRewriterRegistry rewriter) {
this.fetcher = fetcher;
this.preloader = preloader;
this.rewriter = rewriter;
}
/**
* Render the gadget into a string by performing the following steps:
*
* - Retrieve gadget specification information (GadgetSpec, MessageBundle, etc.)
*
* - Fetch any preloaded data needed to handle the request, as handled by Preloader.
*
* - Perform rewriting operations on the output content, handled by Rewriter.
*
* @param gadget The gadget for the rendering operation.
* @return The rendered gadget content
* @throws RenderingException if any issues arise that prevent rendering.
*/
public String render(Gadget gadget) throws RenderingException {
try {
View view = gadget.getCurrentView();
GadgetContext context = gadget.getContext();
GadgetSpec spec = gadget.getSpec();
Preloads preloads = preloader.preload(context, spec);
gadget.setPreloads(preloads);
if (view.getHref() == null) {
return rewriter.rewriteGadget(gadget, view.getContent());
} else {
// TODO: Add current url to GadgetContext to support transitive proxying.
UriBuilder uri = new UriBuilder(view.getHref());
uri.addQueryParameter("lang", context.getLocale().getLanguage());
uri.addQueryParameter("country", context.getLocale().getCountry());
HttpRequest request = new HttpRequest(uri.toUri())
.setIgnoreCache(context.getIgnoreCache())
.setOAuthArguments(new OAuthArguments(view))
.setAuthType(view.getAuthType())
.setSecurityToken(context.getToken())
.setContainer(context.getContainer())
.setGadget(spec.getUrl());
HttpResponse response = fetcher.fetch(request);
if (response.getHttpStatusCode() != HttpResponse.SC_OK) {
throw new RenderingException("Unable to reach remote host. HTTP status " +
response.getHttpStatusCode());
}
return rewriter.rewriteGadget(gadget, response.getResponseAsString());
}
} catch (GadgetException e) {
throw new RenderingException(e.getMessage(), e);
}
}
}