package org.ggp.base.apps.tiltyard;
import java.io.File;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketTimeoutException;
import java.util.Date;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import org.ggp.base.util.crypto.BaseCryptography.EncodedKeyPair;
import org.ggp.base.util.crypto.SignableJSON;
import org.ggp.base.util.files.FileUtils;
import org.ggp.base.util.http.HttpReader;
import org.ggp.base.util.http.HttpRequest;
import org.ggp.base.util.http.HttpWriter;
import org.ggp.base.util.loader.RemoteResourceLoader;
import external.JSON.JSONArray;
import external.JSON.JSONException;
import external.JSON.JSONObject;
/**
* The Tiltyard Request Farm is a multi-threaded web server that opens network
* connections, makes requests, and reports back responses on behalf of a remote
* client. It serves as a backend for intermediary systems that, due to various
* restrictions, cannot make long-lived HTTP connections themselves.
*
* This is the backend for the continuously-running online GGP.org Tiltyard,
* which schedules matches between players around the world and aggregates stats
* based on the outcome of those matches.
*
* SAMPLE INVOCATION (when running locally):
*
* ResourceLoader.load_raw('http://127.0.0.1:9124/' + escape(JSON.stringify({
* "targetPort":9147,"targetHost":"0.player.ggp.org","timeoutClock":30000,
* "forPlayerName":"Webplayer-0","callbackURL":"http://tiltyard.ggp.org/farm/",
* "requestContent":"( play foo bar baz )"})))
*
* Tiltyard Request Farm will open up a network connection to the target, send
* the request string, and wait for the response. Once the response arrives, it
* will close the connection and call the callback, sending the response to the
* remote client that issued the original request.
*
* You shouldn't be running this server unless you are bringing up an instance of the
* online GGP.org Tiltyard or an equivalent service.
*
* @author Sam Schreiber
*/
public final class TiltyardRequestFarm
{
public static final int SERVER_PORT = 9125;
private static final String registrationURL = "http://tiltyard.ggp.org/backends/register/farm";
private static final Object requestCountLock = new Object();
private static int activeBatches = 0;
private static int outgoingRequests = 0;
private static int returningRequests = 0;
private static int abandonedBatches = 0;
static void printBatchStats() {
System.out.println(new Date().getTime() + " [" + new Date() + "]: now " + activeBatches + " active batches, with " + outgoingRequests + " requests outgoing, " + returningRequests + " returning; " + abandonedBatches + " batches abandoned.");
}
public static boolean testMode = false;
static EncodedKeyPair getKeyPair(String keyPairString) {
if (keyPairString == null)
return null;
try {
return new EncodedKeyPair(keyPairString);
} catch (JSONException e) {
return null;
}
}
public static final EncodedKeyPair theBackendKeys = getKeyPair(FileUtils.readFileAsString(new File("src/main/java/org/ggp/base/apps/tiltyard/BackendKeys.json")));
public static String generateSignedPing() {
String zone = null;
try {
Map<String, String> metadataRequestProperties = new HashMap<String, String>();
metadataRequestProperties.put("Metadata-Flavor", "Google");
zone = RemoteResourceLoader.loadRaw("http://metadata/computeMetadata/v1/instance/zone", 1, metadataRequestProperties);
} catch (IOException e1) {
// If we can't acquire the request farm zone, just silently drop it.
}
JSONObject thePing = new JSONObject();
try {
if (zone != null) thePing.put("zone", zone);
thePing.put("lastTimeBlock", (System.currentTimeMillis() / 3600000));
thePing.put("nextTimeBlock", (System.currentTimeMillis() / 3600000)+1);
SignableJSON.signJSON(thePing, theBackendKeys.thePublicKey, theBackendKeys.thePrivateKey);
} catch (JSONException e) {
e.printStackTrace();
}
return thePing.toString();
}
static class RunSingleRequestThread extends Thread {
String targetHost, requestContent, forPlayerName;
int targetPort, timeoutClock;
boolean fastReturn;
JSONObject myResponse;
public RunSingleRequestThread(JSONObject theJSON) throws JSONException {
myResponse = new JSONObject();
myResponse.put("originalRequest", theJSON);
targetPort = theJSON.getInt("targetPort");
targetHost = theJSON.getString("targetHost");
timeoutClock = theJSON.getInt("timeoutClock");
forPlayerName = theJSON.getString("forPlayerName");
requestContent = theJSON.getString("requestContent");
if (theJSON.has("fastReturn")) {
fastReturn = theJSON.getBoolean("fastReturn");
} else {
fastReturn = true;
}
}
@Override
public void run() {
synchronized (requestCountLock) {
outgoingRequests++;
printBatchStats();
}
long startTime = System.currentTimeMillis();
try {
try {
String response = HttpRequest.issueRequest(targetHost, targetPort, forPlayerName, requestContent, timeoutClock);
response = response.replaceAll("\\P{InBasic_Latin}", "");
myResponse.put("response", response);
myResponse.put("responseType", "OK");
} catch (SocketTimeoutException te) {
myResponse.put("responseType", "TO");
} catch (IOException ie) {
myResponse.put("responseType", "CE");
}
} catch (JSONException je) {
throw new RuntimeException(je);
}
synchronized (requestCountLock) {
outgoingRequests--;
printBatchStats();
}
long timeSpent = System.currentTimeMillis() - startTime;
if (!fastReturn && timeSpent < timeoutClock) {
try {
Thread.sleep(timeoutClock - timeSpent);
} catch (InterruptedException e) {
;
}
}
}
public JSONObject getResponse() {
return myResponse;
}
}
// Connections are run asynchronously in their own threads.
static class RunBatchRequestThread extends Thread {
String originalRequest, callbackURL;
Set<RunSingleRequestThread> theRequestThreads;
Set<String> activeRequests;
public RunBatchRequestThread(Socket connection, Set<String> activeRequests) throws IOException, JSONException {
String line = HttpReader.readAsServer(connection);
System.out.println(new Date().getTime() + " [" + new Date() + "] received batch request: " + line);
String response = null;
if (line.equals("ping")) {
response = generateSignedPing();
} else {
synchronized (activeRequests) {
if (activeRequests.contains(line)) {
System.out.println("Got duplicate request; ignoring.");
connection.close();
return;
} else {
activeRequests.add(line);
}
this.activeRequests = activeRequests;
}
JSONObject theBatchJSON = new JSONObject(line);
JSONArray theRequests = theBatchJSON.getJSONArray("requests");
theRequestThreads = new HashSet<RunSingleRequestThread>();
for (int i = 0; i < theRequests.length(); i++) {
JSONObject aRequest = theRequests.getJSONObject(i);
RunSingleRequestThread aRequestThread = new RunSingleRequestThread(aRequest);
theRequestThreads.add(aRequestThread);
}
callbackURL = theBatchJSON.getString("callbackURL");
originalRequest = line;
response = "okay";
}
HttpWriter.writeAsServer(connection, response);
connection.close();
}
@Override
public void run() {
if (originalRequest == null)
return;
synchronized (requestCountLock) {
activeBatches++;
printBatchStats();
}
// Start running all of the requests in the batch parallel.
for (RunSingleRequestThread aRequestThread : theRequestThreads) {
aRequestThread.start();
}
// Wait for all of the requests to finish; aggregate them into a batch response.
JSONObject responseJSON = new JSONObject();
JSONArray responses = new JSONArray();
for (RunSingleRequestThread aRequestThread : theRequestThreads) {
try {
aRequestThread.join();
responses.put(aRequestThread.getResponse());
} catch (InterruptedException e) {
e.printStackTrace();
}
}
try {
responseJSON.put("responses", responses);
if (!testMode) {
SignableJSON.signJSON(responseJSON, theBackendKeys.thePublicKey, theBackendKeys.thePrivateKey);
}
} catch (JSONException je) {
je.printStackTrace();
synchronized (requestCountLock) {
abandonedBatches++;
activeBatches--;
printBatchStats();
}
synchronized (activeRequests) {
activeRequests.remove(originalRequest);
}
return;
}
// Send the batch response back to the callback URL.
synchronized (requestCountLock) {
returningRequests++;
printBatchStats();
}
int nPostAttempts = 0;
while (true) {
try {
RemoteResourceLoader.postRawWithTimeout(callbackURL, responseJSON.toString(), Integer.MAX_VALUE);
break;
} catch (IOException ie) {
nPostAttempts++;
try {
Thread.sleep(nPostAttempts < 10 ? 1000 : 15000);
} catch (InterruptedException e) {
;
}
}
}
synchronized (requestCountLock) {
returningRequests--;
activeBatches--;
printBatchStats();
if (activeBatches == 0) {
System.gc();
System.out.println("Garbage collecting since there are no active batches.");
}
}
synchronized (activeRequests) {
activeRequests.remove(originalRequest);
}
}
}
static class TiltyardRegistration extends Thread {
@Override
public void run() {
// Send a registration ping to Tiltyard every five minutes.
while (true) {
try {
RemoteResourceLoader.postRawWithTimeout(registrationURL, generateSignedPing(), 2500);
} catch (Exception e) {
e.printStackTrace();
}
try {
Thread.sleep(5 * 60 * 1000);
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
@SuppressWarnings("resource")
public static void main(String[] args) {
ServerSocket listener = null;
try {
listener = new ServerSocket(SERVER_PORT);
} catch (IOException e) {
System.err.println("Could not open server on port " + SERVER_PORT + ": " + e);
e.printStackTrace();
return;
}
if (!testMode) {
if (theBackendKeys == null) {
System.err.println("Could not load cryptographic keys for signing request responses.");
return;
}
new TiltyardRegistration().start();
}
Set<String> activeRequests = new HashSet<String>();
while (true) {
try {
Socket connection = listener.accept();
RunBatchRequestThread handlerThread = new RunBatchRequestThread(connection, activeRequests);
handlerThread.start();
} catch (Exception e) {
System.err.println(e);
}
}
}
}