@Override
public void fetch(HttpServletRequest request, HttpServletResponse response)
throws IOException, GadgetException {
if (request.getHeader("If-Modified-Since") != null) {
response.setStatus(HttpServletResponse.SC_NOT_MODIFIED);
return;
}
String host = request.getHeader("Host");
if (!lockedDomainService.isSafeForOpenProxy(host)) {
// Force embedded images and the like to their own domain to avoid XSS
// in gadget domains.
String msg =
"Embed request for url "
+ getParameter(request, URL_PARAM, "")
+ " made to wrong domain "
+ host;
logger.info(msg);
throw new GadgetException(GadgetException.Code.INVALID_PARAMETER, msg);
}
HttpRequest rcr = buildHttpRequest(request);
HttpResponse results = fetcher.fetch(rcr);
if (contentRewriterRegistry != null) {
results = contentRewriterRegistry.rewriteHttpResponse(rcr, results);
}
setResponseHeaders(request, response, results);
for (Map.Entry<String, List<String>> entry : results.getHeaders().entrySet()) {
String name = entry.getKey();
if (!DISALLOWED_RESPONSE_HEADERS.contains(name.toLowerCase())) {
for (String value : entry.getValue()) {
response.addHeader(name, value);
}
}
}
if (rcr.getRewriteMimeType() != null) {
response.setContentType(rcr.getRewriteMimeType());
}
if (results.getHttpStatusCode() != HttpResponse.SC_OK) {
response.sendError(results.getHttpStatusCode());
}
IOUtils.copy(results.getResponse(), response.getOutputStream());
}
/**
* Attempts to render the requested gadget.
*
* @return The results of the rendering attempt.
* <p>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;
}
}