/*
* Copyright 2009 Prime Technology.
*
* Licensed 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.primefaces.resource;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.primefaces.resource.stream.CSSResourceStreamer;
import org.primefaces.resource.stream.DefaultResourceStreamer;
import org.primefaces.resource.stream.ResourceStreamer;
/**
*
* ResourceServlet is responsible for streaming resources like css, script, images and etc to the client.
* Streaming is done via ResourceStreamers and resources are forced to be cached indefinitely using convenient response headers.
*/
public class ResourceServlet extends HttpServlet {
private static final Logger logger = Logger.getLogger(ResourceServlet.class.getName());
private static Map<String,String> mimeTypes;
private List<ResourceStreamer> resourceStreamers;
@Override
public void init(ServletConfig config) throws ServletException {
super.init(config);
initMimeTypes();
initResourceStreamers();
}
private void initMimeTypes() {
mimeTypes = new HashMap<String, String>();
mimeTypes.put("css", "text/css");
mimeTypes.put("js", "text/js");
mimeTypes.put("jpg", "image/jpeg");
mimeTypes.put("jpeg", "image/jpeg");
mimeTypes.put("png", "image/png");
mimeTypes.put("gif", "image/gif");
mimeTypes.put("swf", "application/x-shockwave-flash");
}
private void initResourceStreamers() {
resourceStreamers = new ArrayList<ResourceStreamer>();
resourceStreamers.add(new DefaultResourceStreamer());
resourceStreamers.add(new CSSResourceStreamer());
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String resourcePath = ResourceUtils.RESOURCE_FOLDER + getResourcePath(req.getRequestURI());
URL url = ResourceServlet.class.getResource(resourcePath);
if(url == null) {
logger.log(Level.SEVERE, "Resource \"{0}\" not found", resourcePath);
resp.sendError(HttpServletResponse.SC_NOT_FOUND);
return;
}
if(logger.isLoggable(Level.FINE))
logger.log(Level.FINE, "Streaming resource \"{0}\"", resourcePath);
InputStream inputStream = null;
try {
inputStream = ResourceServlet.class.getResourceAsStream(resourcePath);
String mimeType = getResourceContentType(resourcePath);
resp.setContentType(mimeType);
resp.setStatus(200);
setCaching(resp);
streamResource(req, resp, mimeType, inputStream);
if(logger.isLoggable(Level.FINE))
logger.log(Level.FINE, "Resource \"{0}\" streamed succesfully", resourcePath);
}
catch (Exception exception) {
logger.log(Level.SEVERE, "Error in streaming resource \"{0}\". Exception is \"{1}\"", new Object[]{resourcePath, exception.getMessage()});
} finally {
inputStream.close();
resp.getOutputStream().flush();
resp.getOutputStream().close();
}
}
private void streamResource(HttpServletRequest req, HttpServletResponse resp, String mimeType, InputStream inputStream) throws IOException {
for(ResourceStreamer streamer : resourceStreamers) {
if(streamer.isAppropriateStreamer(mimeType))
streamer.stream(req, resp, inputStream);
}
}
private void setCaching(HttpServletResponse response) {
long now = System.currentTimeMillis();
long oneYear = 31363200000L;
response.setHeader("Cache-Control", "Public");
response.setDateHeader("Expires", now + oneYear);
}
protected String getResourcePath(String requestURI) {
int patternIndex = requestURI.indexOf(ResourceUtils.RESOURCE_VERSION_PATTERN);
return requestURI.substring(patternIndex + ResourceUtils.RESOURCE_VERSION_PATTERN.length(), requestURI.length());
}
protected String getResourceContentType(String resourcePath) {
String resourceFileExtension = getResourceFileExtension(resourcePath);
return mimeTypes.get(resourceFileExtension);
}
protected String getResourceFileExtension(String resourcePath) {
String parsed[] = resourcePath.split("\\.");
return parsed[parsed.length -1];
}
}