com.btr.proxy.selector.pac.PacProxySelector Maven / Gradle / Ivy
package com.btr.proxy.selector.pac;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.Proxy;
import java.net.ProxySelector;
import java.net.SocketAddress;
import java.net.URI;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Locale;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.commons.lang3.StringUtils;
/*****************************************************************************
* ProxySelector that will use a PAC script to find an proxy for a given URI.
*
* @author Bernd Rosstauscher ([email protected]) Copyright 2009
****************************************************************************/
public class PacProxySelector extends ProxySelector {
protected static final Logger log = Logger.getLogger(PacProxySelector.class
.getCanonicalName());
private final static int PROXY_TYPE_LEN = 6;
private static final String PAC_PROXY = "PROXY";
private static final String PAC_SOCKS = "SOCKS";
private static final String PAC_DIRECT = "DIRECT";
private PacScriptParser pacScriptParser;
private static volatile boolean enabled = true;
/*************************************************************************
* Constructor
*
* @param pacSource
* the source for the PAC file.
************************************************************************/
public PacProxySelector(PacScriptSource pacSource) {
super();
selectEngine(pacSource);
}
/*************************************************************************
* Can be used to enable / disable the proxy selector. If disabled it will
* return DIRECT for all urls.
*
* @param enable
* the new status to set.
************************************************************************/
public static void setEnabled(boolean enable) {
enabled = enable;
}
/*************************************************************************
* Checks if the selector is currently enabled.
*
* @return true if enabled else false.
************************************************************************/
public static boolean isEnabled() {
return enabled;
}
/*************************************************************************
* Selects one of the available PAC parser engines.
*
* @param pacSource
* to use as input.
************************************************************************/
private void selectEngine(PacScriptSource pacSource) {
try {
log.log(Level.INFO, "Using javax.script JavaScript engine.");
this.pacScriptParser = new JavaxPacScriptParser(pacSource);
} catch (Exception e) {
log.log(Level.INFO, "PAC parser error.", e);
}
}
/*************************************************************************
* connectFailed
*
* @see java.net.ProxySelector#connectFailed(java.net.URI,
* java.net.SocketAddress, java.io.IOException)
************************************************************************/
@Override
public void connectFailed(URI uri, SocketAddress sa, IOException ioe) {
// Not used.
}
/*************************************************************************
* select
*
* @see java.net.ProxySelector#select(java.net.URI)
************************************************************************/
@Override
public List select(URI uri) {
if (uri == null) {
throw new IllegalArgumentException("URI must not be null.");
}
// Fix for Java 1.6.16+ where we get a infinite loop because
// URL.connect(Proxy.NO_PROXY) does not work as expected.
if (!enabled) {
return noProxyList();
}
return findProxy(uri);
}
/*************************************************************************
* Evaluation of the given URL with the PAC-file.
*
* Two cases can be handled here: DIRECT Fetch the object directly from the
* content HTTP server denoted by its URL PROXY name:port Fetch the object via
* the proxy HTTP server at the given location (name and port)
*
* @param uri
* URI to be evaluated.
* @return Proxy-object list as result of the evaluation.
************************************************************************/
private List findProxy(URI uri) {
try {
List proxies = new ArrayList();
String parseResult = this.pacScriptParser.evaluate(uri.toString(),
uri.getHost());
String[] proxyDefinitions = parseResult.split("[;]");
for (String proxyDef : proxyDefinitions) {
if (!StringUtils.isBlank(proxyDef)) {
proxies.add(buildProxyFromPacResult(proxyDef));
}
}
return proxies;
} catch (ProxyEvaluationException e) {
log.log(Level.INFO, "PAC resolving error.", e);
return noProxyList();
}
}
/*************************************************************************
* The proxy evaluator will return a proxy string. This method will take this
* string and build a matching Proxy for it.
*
* @param pacResult
* the result from the PAC parser.
* @return a Proxy
************************************************************************/
public static Proxy buildProxyFromPacResult(String pacResult) {
if (StringUtils.isBlank(pacResult) || pacResult.trim().toUpperCase(Locale.ENGLISH).startsWith(PAC_DIRECT)) {
return Proxy.NO_PROXY;
}
String proxyDef = pacResult.trim();
Proxy.Type type = Proxy.Type.HTTP;
if (proxyDef.toUpperCase(Locale.ENGLISH).startsWith(PAC_SOCKS)) {
type = Proxy.Type.SOCKS;
} else if (!proxyDef.toUpperCase(Locale.ENGLISH).startsWith(PAC_PROXY)) {
return Proxy.NO_PROXY;
}
String host = proxyDef.substring(PROXY_TYPE_LEN);
Integer port = DEFAULT_PROXY_PORT;
// Split port from host
int indexOfPort = host.indexOf(':');
if (indexOfPort != -1) {
port = Integer.parseInt(host.substring(indexOfPort + 1).trim());
host = host.substring(0, indexOfPort).trim();
}
SocketAddress adr = InetSocketAddress.createUnresolved(host, port);
return new Proxy(type, adr);
}
public static final int DEFAULT_PROXY_PORT = 80;
private static List noProxyList;
/*************************************************************************
* Gets an unmodifiable proxy list that will have as it's only entry an DIRECT
* proxy.
*
* @return a list with a DIRECT proxy in it.
************************************************************************/
public static synchronized List noProxyList() {
if (noProxyList == null) {
ArrayList list = new ArrayList(1);
list.add(Proxy.NO_PROXY);
noProxyList = Collections.unmodifiableList(list);
}
return noProxyList;
}
/*************************************************************************
* Build a PAC proxy selector for the given URL.
*
* @param url
* to fetch the PAC script from.
* @return a PacProxySelector or null if it is not possible to build a working
* selector.
************************************************************************/
public static PacProxySelector buildPacSelectorForUrl(String url) {
PacProxySelector result = null;
PacScriptSource pacSource = new UrlPacScriptSource(url);
if (pacSource.isScriptValid()) {
result = new PacProxySelector(pacSource);
}
return result;
}
}