/*
* Weblounge: Web Content Management System
* Copyright (c) 2003 - 2011 The Weblounge Team
* http://entwinemedia.com/weblounge
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
package ch.entwine.weblounge.kernel.shared;
import ch.entwine.weblounge.common.impl.request.Http11ProtocolHandler;
import ch.entwine.weblounge.common.impl.request.Http11ResponseType;
import ch.entwine.weblounge.common.url.PathUtils;
import ch.entwine.weblounge.common.url.UrlUtils;
import org.apache.commons.io.FilenameUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.tika.Tika;
import org.osgi.framework.Bundle;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import javax.activation.FileTypeMap;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet that serves both resources from an arbitrary directory or a bundle's
* classpath.
* <p>
* Note that in cases where both a directory and a bundle have been configured,
* and a resource exists in both places, the directory takes precedence. This
* allows to overwrite
*/
public class WebloungeResourcesServlet extends HttpServlet {
/** Serial version uid */
private static final long serialVersionUID = 4007081684493732350L;
/** Logger */
private static final Logger logger = LoggerFactory.getLogger(WebloungeSharedResources.class);
/** Directory with external resources */
protected File resourcesDir = null;
/** Bundle context */
private Bundle bundle = null;
/** The path into the bundle's classpath */
private String bundlePath = null;
/** The servlet configuration */
private ServletConfig servletConfig = null;
/** Mime type detector */
private Tika mimeTypeDetector = new Tika();
/**
* Creates a new servlet that serves resources from the bundle's classpath.
* The resources are exposed in such a way that <code>bundlePath</code> will
* be mounted as the root.
*
* @param bundle
* the bundle
* @param bundlePath
* path into the bundle's classpath
*/
public WebloungeResourcesServlet(Bundle bundle, String bundlePath) {
this(null, bundle, bundlePath);
if (bundle == null)
throw new IllegalArgumentException("Bundle must not be null");
if (StringUtils.isBlank(bundlePath))
throw new IllegalArgumentException("Bundle path must not be blank");
}
/**
* Creates a new servlet that serves resources from an arbitrary directory on
* the filesystem.
*
* @param resourcesDir
* directory for resources
*/
public WebloungeResourcesServlet(File resourcesDir) {
this(resourcesDir, null, null);
if (resourcesDir == null)
throw new IllegalArgumentException("Resources directory must not be null");
}
/**
* Creates a new servlet that serves both resources from an arbitrary
* directory on the filesystem and the bundle's classpath.
*
* @param resourcesDir
* directory for external resources
* @param bundle
* the bundle
* @param bundlePath
* path into the bundle's classpath
* @throws IllegalArgumentException
* if both <code>resourcesDir</code> and <code>bundle</code> are
* <code>null</code>
*/
public WebloungeResourcesServlet(File resourcesDir, Bundle bundle,
String bundlePath) {
this.resourcesDir = resourcesDir;
this.bundle = bundle;
this.bundlePath = bundlePath;
if (resourcesDir == null && (bundle == null || StringUtils.isBlank(bundlePath)))
throw new IllegalArgumentException("Either one of resources directory or bundle and bundle path must be provided");
}
/**
* {@inheritDoc}
*
* @see javax.servlet.GenericServlet#init(javax.servlet.ServletConfig)
*/
@Override
public void init(ServletConfig config) throws ServletException {
this.servletConfig = config;
}
/**
* {@inheritDoc}
*
* @see javax.servlet.http.HttpServlet#service(javax.servlet.ServletRequest,
* javax.servlet.ServletResponse)
*/
@Override
public void service(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Http11ResponseType responseType = null;
String requestPath = request.getPathInfo();
URL url = null;
long lastModified = 0L;
long contentLength = 0L;
// Are we looking at the top-level directory?
if (requestPath == null) {
response.sendError(HttpServletResponse.SC_FORBIDDEN);
return;
}
// Serve from directory
if (resourcesDir != null) {
File resource = new File(PathUtils.concat(resourcesDir.getAbsolutePath(), requestPath));
// Don't serve directory listings
if (resource.isDirectory() || StringUtils.isBlank((FilenameUtils.getExtension(requestPath)))) {
response.sendError(HttpServletResponse.SC_FORBIDDEN);
return;
}
// Check if the file exists
if (resource.exists() && resource.canRead()) {
url = resource.toURI().toURL();
}
}
// Serve from bundle if the same resource wasn't loaded from the directory
// already
if (bundle != null && url == null) {
String resourcePath = UrlUtils.concat(bundlePath, requestPath);
url = bundle.getEntry(resourcePath);
}
// Check if the resource exists
if (url == null) {
response.sendError(HttpServletResponse.SC_NOT_FOUND);
return;
}
URLConnection conn = url.openConnection();
contentLength = conn.getContentLength();
lastModified = conn.getLastModified();
// A mime type would be nice as well
String mimeType = servletConfig.getServletContext().getMimeType(requestPath);
InputStream is = null;
if (StringUtils.isBlank(mimeType)) {
mimeType = mimeTypeDetector.detect(requestPath);
if (mimeType == null) {
try {
is = url.openStream();
mimeType = mimeTypeDetector.detect(is);
} catch (IOException e) {
logger.warn("Error detecting mime type: {}", e.getMessage());
} finally {
IOUtils.closeQuietly(is);
}
}
}
String encoding = null;
// Try to get mime type and content encoding from resource
if (mimeType == null)
mimeType = FileTypeMap.getDefaultFileTypeMap().getContentType(requestPath);
if (mimeType == null)
mimeType = conn.getContentType();
encoding = conn.getContentEncoding();
if (mimeType != null) {
if (encoding != null)
mimeType += ";" + encoding;
response.setContentType(mimeType);
}
// Send the response back to the client
is = url.openStream();
try {
logger.debug("Serving {}", url);
responseType = Http11ProtocolHandler.analyzeRequest(request, lastModified, 0, contentLength);
if (!Http11ProtocolHandler.generateResponse(response, responseType, is)) {
logger.warn("I/O error while generating content from {}", url);
}
} finally {
IOUtils.closeQuietly(is);
}
}
/**
* {@inheritDoc}
*
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
return "Weblounge bundle resources servlet";
}
}