//
// ProxyHandler
// Copyright 2004 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
// Copyright 2011 by Florian Richter
// First released 2011 at http://yacy.net
//
// $LastChangedDate$
// $LastChangedRevision$
// $LastChangedBy$
//
// This library 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 2.1 of the License, or (at your option) any later version.
//
// This library 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 in the file lgpl21.txt
// If not, see <http://www.gnu.org/licenses/>.
//
package net.yacy.http;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.SocketException;
import java.util.Date;
import java.util.Enumeration;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.yacy.cora.date.GenericFormatter;
import net.yacy.cora.document.id.DigestURL;
import net.yacy.cora.protocol.ClientIdentification;
import net.yacy.cora.protocol.Domains;
import net.yacy.cora.protocol.HeaderFramework;
import net.yacy.cora.protocol.RequestHeader;
import net.yacy.cora.protocol.ResponseHeader;
import net.yacy.cora.protocol.http.HTTPClient;
import net.yacy.crawler.data.Cache;
import net.yacy.crawler.retrieval.Response;
import net.yacy.document.TextParser;
import net.yacy.server.http.HTTPDProxyHandler;
import net.yacy.server.http.MultiOutputStream;
import org.apache.http.Header;
import org.apache.http.HttpResponse;
import org.eclipse.jetty.server.Handler;
import org.eclipse.jetty.server.Request;
/**
* jetty http handler
* proxies request, caches responses and adds urls to crawler
*/
public class ProxyHandler extends AbstractRemoteHandler implements Handler {
protected int timeout = 10000;
@Override
protected void doStart() throws Exception {
super.doStart();
timeout = sb.getConfigInt("proxy.clientTimeout", 10000);
}
private void convertHeaderToJetty(HttpResponse in, HttpServletResponse out) {
for(Header h: in.getAllHeaders()) {
out.addHeader(h.getName(), h.getValue());
}
}
private void cleanResponseHeader(HttpResponse headers) {
headers.removeHeaders(HeaderFramework.CONTENT_ENCODING);
headers.removeHeaders(HeaderFramework.CONTENT_LENGTH);
}
private void deleteFromCache(final byte[] hash) {
// long size = -1;
ResponseHeader rh = Cache.getResponseHeader(hash);
if (rh != null) {
// delete the cache
// if ((size = rh.getContentLength()) == 0) {
// byte[] b = Cache.getContent(hash);
// if (b != null) size = b.length;
// }
try {
Cache.delete(hash);
} catch (final IOException e) {
// log refresh miss
HTTPDProxyHandler.proxyLog.fine(e.getMessage());
}
}
}
private void storeToCache(final Response yacyResponse, final byte[] cacheArray) {
final Thread t = new Thread() {
@Override
public void run() {
if (yacyResponse == null) return;
this.setName("ProxyHandler.storeToCache(" + yacyResponse.url().toNormalform(true) + ")");
// the cache does either not exist or is (supposed to be) stale
deleteFromCache(yacyResponse.url().hash());
if (cacheArray == null || cacheArray.length <= 0) return;
yacyResponse.setContent(cacheArray);
try {
Cache.store(yacyResponse.url(), yacyResponse.getResponseHeader(), cacheArray);
sb.toIndexer(yacyResponse);
} catch (IOException e) {
//log.logWarning("cannot write " + response.url() + " to Cache (1): " + e.getMessage(), e);
}
}
};
t.setPriority(Thread.MIN_PRIORITY);
t.start();
}
@Override
public void handleRemote(String target, Request baseRequest, HttpServletRequest request,
HttpServletResponse response) throws IOException, ServletException {
sb.proxyLastAccess = System.currentTimeMillis();
RequestHeader proxyHeaders = ProxyHandler.convertHeaderFromJetty(request);
setProxyHeaderForClient(request, proxyHeaders);
final HTTPClient client = new HTTPClient(ClientIdentification.yacyProxyAgent);
client.setTimout(timeout);
client.setHeader(proxyHeaders.entrySet());
client.setRedirecting(false);
// send request
try {
String queryString = request.getQueryString() != null ? "?" + request.getQueryString() : "";
DigestURL digestURI = new DigestURL(request.getScheme(), request.getServerName(), request.getServerPort(), request.getRequestURI() + queryString);
if (request.getMethod().equals(HeaderFramework.METHOD_GET)) {
client.GET(digestURI, false);
} else if (request.getMethod().equals(HeaderFramework.METHOD_POST)) {
client.POST(digestURI, request.getInputStream(), request.getContentLength(), false);
} else if (request.getMethod().equals(HeaderFramework.METHOD_HEAD)) {
client.HEADResponse(digestURI, false);
} else {
throw new ServletException("Unsupported Request Method");
}
HttpResponse clientresponse = client.getHttpResponse();
int statusCode = clientresponse.getStatusLine().getStatusCode();
final ResponseHeader responseHeaderLegacy = new ResponseHeader(statusCode, clientresponse.getAllHeaders());
if (responseHeaderLegacy.isEmpty()) {
throw new SocketException(clientresponse.getStatusLine().toString());
}
cleanResponseHeader(clientresponse);
// reserver cache entry
final net.yacy.crawler.retrieval.Request yacyRequest = new net.yacy.crawler.retrieval.Request(
null,
digestURI,
null, //requestHeader.referer() == null ? null : new DigestURI(requestHeader.referer()).hash(),
"",
responseHeaderLegacy.lastModified(),
sb.crawler.defaultProxyProfile.handle(),
0,
sb.crawler.defaultProxyProfile.timezoneOffset()); //sizeBeforeDelete < 0 ? 0 : sizeBeforeDelete);
final Response yacyResponse = new Response(
yacyRequest,
null,
responseHeaderLegacy,
sb.crawler.defaultProxyProfile,
false,
null
);
final String storeError = yacyResponse.shallStoreCacheForProxy();
final boolean storeHTCache = yacyResponse.profile().storeHTCache();
final String supportError = TextParser.supports(yacyResponse.url(), yacyResponse.getMimeType());
if (
/*
* Now we store the response into the htcache directory if
* a) the response is cacheable AND
*/
(storeError == null) &&
/*
* b) the user has configured to use the htcache OR
* c) the content should be indexed
*/
((storeHTCache) || (supportError != null))
) {
// we don't write actually into a file, only to RAM, and schedule writing the file.
int l = responseHeaderLegacy.size();
final ByteArrayOutputStream byteStream = new ByteArrayOutputStream((l < 32) ? 32 : l);
final OutputStream toClientAndMemory = new MultiOutputStream(new OutputStream[] {response.getOutputStream(), byteStream});
convertHeaderToJetty(clientresponse, response);
response.setStatus(statusCode);
client.writeTo(toClientAndMemory);
// cached bytes
storeToCache(yacyResponse, byteStream.toByteArray());
} else {
// no caching
/*if (log.isFine()) log.logFine(reqID +" "+ url.toString() + " not cached." +
" StoreError=" + ((storeError==null)?"None":storeError) +
" StoreHTCache=" + storeHTCache +
" SupportError=" + supportError);*/
convertHeaderToJetty(clientresponse, response);
response.setStatus(statusCode);
if (statusCode == HttpServletResponse.SC_OK) { // continue to serve header to client e.g. HttpStatus = 302 (while skiping content)
client.writeTo(response.getOutputStream()); // may throw exception on httpStatus=302 while gzip encoded inputstream
}
}
} catch (final SocketException se) {
throw new ServletException("Socket Exception: " + se.getMessage());
} finally {
client.finish();
}
// we handled this request, break out of handler chain
logProxyAccess(request);
baseRequest.setHandled(true);
}
/**
* Convert ServletRequest header to modifiable YaCy RequestHeader
*
* @param request ServletRequest
* @return RequestHeader created from ServletRequest
*/
public static RequestHeader convertHeaderFromJetty(HttpServletRequest request) {
RequestHeader result = new RequestHeader();
Enumeration<String> headerNames = request.getHeaderNames();
while (headerNames.hasMoreElements()) {
String headerName = headerNames.nextElement();
Enumeration<String> headers = request.getHeaders(headerName);
while (headers.hasMoreElements()) {
String header = headers.nextElement();
result.add(headerName, header);
}
}
return result;
}
/**
* adds specific header elements for the connection of the internal
* httpclient to the remote server according to local config
*
* @param header header for http client (already preset with headers from
* original ServletRequest)
* @param origServletRequest original request/header
*/
private void setProxyHeaderForClient(final HttpServletRequest origServletRequest, final HeaderFramework header) {
header.remove(RequestHeader.KEEP_ALIVE);
header.remove(HeaderFramework.CONTENT_LENGTH);
// setting the X-Forwarded-For header
if (sb.getConfigBool("proxy.sendXForwardedForHeader", true)) {
String ip = origServletRequest.getRemoteAddr();
if (!Domains.isThisHostIP(ip)) { // if originator is local host no user ip to forward (= request from localhost)
header.put(HeaderFramework.X_FORWARDED_FOR, origServletRequest.getRemoteAddr());
}
}
String httpVersion = origServletRequest.getProtocol();
HTTPDProxyHandler.modifyProxyHeaders(header, httpVersion);
}
public final static synchronized void logProxyAccess(HttpServletRequest request) {
final StringBuilder logMessage = new StringBuilder(80);
// Timestamp
logMessage.append(GenericFormatter.SHORT_SECOND_FORMATTER.format(new Date()));
logMessage.append(' ');
// Remote Host
final String clientIP = request.getRemoteAddr();
logMessage.append(clientIP);
logMessage.append(' ');
// Method
final String requestMethod = request.getMethod();
logMessage.append(requestMethod);
logMessage.append(' ');
// URL
logMessage.append(request.getRequestURL());
final String requestArgs = request.getQueryString();
if (requestArgs != null) {
logMessage.append("?").append(requestArgs);
}
HTTPDProxyHandler.proxyLog.fine(logMessage.toString());
}
}