Implemented server to manage a list of available servers on the internet.

- Implemented a server manager that keeps track of servers & room codes, and removes old servers
- Implemented queries to find a server with a specific room code
- Implemented protocol to register servers

#story[1281]

src/main/java/seng302/App.java

@@ -10,11 +10,13 @@ import org.apache.commons.cli.Options;
 import org.apache.commons.cli.ParseException;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import seng302.serverRepository.ServerRepository;
 import seng302.visualiser.controllers.ViewManager;
 
 public class App extends Application {
 
     private static Logger logger = LoggerFactory.getLogger(App.class);
+    private static boolean isRunningAsCache = false;
 
     public static void parseArgs(String[] args) throws ParseException {
         Options options = new Options();
@@ -25,9 +27,14 @@ public class App extends Application {
             .getLogger(Logger.ROOT_LOGGER_NAME);
 
         options.addOption("debugLevel", true, "Set the application debug level");
+        options.addOption("runAsCache", false, "Run as a server cache for server discovery");
 
         cmd = parser.parse(options, args);
 
+        if (cmd.hasOption("runAsCache")){
+            isRunningAsCache = true;
+        }
+
         if (cmd.hasOption("debugLevel")) {
 
             switch (cmd.getOptionValue("debugLevel")) {
@@ -67,14 +74,19 @@ public class App extends Application {
     }
 
 
-    public static void main(String[] args) {
+    public static void main(String[] args) throws Exception {
         try {
             parseArgs(args);
         } catch (ParseException e) {
             logger.error("Could not parse command line arguments");
         }
 
-        launch(args);
+        if (!isRunningAsCache){
+            launch(args);
+        }
+        else{
+            ServerRepository serverRepository = new ServerRepository();
+        }
     }
 }
 

src/main/java/seng302/gameServer/ServerAdvertiser.java

@@ -1,5 +1,9 @@
 package seng302.gameServer;
 
+import com.sun.org.apache.xpath.internal.operations.Bool;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import javax.jmdns.JmDNS;
 import javax.jmdns.ServiceInfo;
 import java.io.IOException;
@@ -27,7 +31,7 @@ public class ServerAdvertiser {
      */
     private static String SERVICE = "_partyatsea";
     private static String PROTOCOL = "_tcp";
-    public static String SERVICE_TYPE = SERVICE + "." + PROTOCOL + ".local.";
+    public static String SERVICE_TYPE = SERVICE + "." + PROTOCOL + ".homekit.bonjour.michaelrausch.nz.";
 
     private static ServerAdvertiser instance = null;
     private static JmDNS jmdnsInstance = null;

src/main/java/seng302/gameServer/ServerDescription.java

@@ -7,6 +7,10 @@ public class ServerDescription {
     private String serverName;
     private String mapName;
     private Integer numPlayers;
+    private Long lastUpdated;
+    private Long lastRefreshed;
+
+    private static Long EXPIRY_INTERVAL = 5000L;
 
     public ServerDescription(String serverName, String mapName, Integer numPlayers, Integer capacity, String address, Integer portNum){
         this.serverName = serverName;
@@ -15,6 +19,7 @@ public class ServerDescription {
         this.address = address;
         this.portNum = portNum;
         this.capacity = capacity;
+        lastUpdated = System.currentTimeMillis();
     }
 
 
@@ -80,4 +85,20 @@ public class ServerDescription {
         return this.getName().hashCode() + this.getAddress().hashCode() +
                 this.portNumber().hashCode() + this.getMapName().hashCode();
     }
+
+    public Boolean hasExpired(){
+        return System.currentTimeMillis() - lastUpdated > EXPIRY_INTERVAL;
+    }
+
+    public Boolean serverShouldBeRemoved() {
+        if (lastRefreshed == null) return false;
+
+        System.out.println("SBR" + (System.currentTimeMillis() - lastRefreshed > EXPIRY_INTERVAL));
+        return System.currentTimeMillis() - lastRefreshed > EXPIRY_INTERVAL;
+    }
+
+    public void hasBeenRefreshed(){
+        System.out.println("Was refreshed");
+        lastRefreshed = System.currentTimeMillis();
+    }
 }

src/main/java/seng302/gameServer/messages/MessageType.java

@@ -21,7 +21,10 @@ public enum MessageType {
     REGISTRATION_REQUEST(101),
     REGISTRATION_RESPONSE(102),
     CUSTOMIZATION_REQUEST(103),
-    CUSTOMIZATION_RESPONSE(104);
+    CUSTOMIZATION_RESPONSE(104),
+    REPO_REGISTRATION_REQUEST(201),
+    ROOM_CODE_REQUEST(202),
+    LOBBY_REQUEST(203);
 
 
     private int code;

src/main/java/seng302/gameServer/messages/RoomCodeRequest.java

@@ -0,0 +1,24 @@
+package seng302.gameServer.messages;
+
+public class RoomCodeRequest extends Message{
+    private int size = 0;
+
+    @Override
+    public int getSize() {
+        return size;
+    }
+
+    public RoomCodeRequest(String roomCode){
+        size = roomCode.length() + 6;
+
+        setHeader(new Header(MessageType.ROOM_CODE_REQUEST, 0x01, (short)getSize()));
+        allocateBuffer();
+        writeHeaderToBuffer();
+
+        putInt(roomCode.length(), 6);
+        putBytes(roomCode.getBytes());
+
+        writeCRC();
+        rewind();
+    }
+}

src/main/java/seng302/gameServer/messages/ServerRegistrationMessage.java

@@ -0,0 +1,40 @@
+package seng302.gameServer.messages;
+
+public class ServerRegistrationMessage extends Message {
+    private int size;
+    @Override
+    public int getSize() {
+        return size;
+    }
+
+    public ServerRegistrationMessage(String serverName, String mapName, String address, int port, int players, int capacity, String roomCode){
+        size = serverName.getBytes().length + mapName.length() + address.length() + roomCode.length() + 36;
+
+        setHeader(new Header(MessageType.REPO_REGISTRATION_REQUEST, 0x01, (short) getSize()));
+        allocateBuffer();
+        writeHeaderToBuffer();
+
+        int nameLength = serverName.length();
+        int mapNameLength = mapName.length();
+        int addressLength = address.length();
+        int roomCodeLength = roomCode.length();
+
+        // Put fields here
+        putInt(nameLength, 6);
+        putInt(mapNameLength, 6);
+        putInt(addressLength, 6);
+        putInt(roomCodeLength, 6);
+
+        putInt(port, 4);
+        putInt(players, 4);
+        putInt(capacity, 4);
+
+        putBytes(serverName.getBytes());
+        putBytes(mapName.getBytes());
+        putBytes(address.getBytes());
+        putBytes(roomCode.getBytes());
+
+        writeCRC();
+        rewind();
+    }
+}

src/main/java/seng302/model/stream/packets/PacketType.java

@@ -20,7 +20,9 @@ public enum PacketType {
     RACE_REGISTRATION_REQUEST,
     RACE_REGISTRATION_RESPONSE,
     RACE_CUSTOMIZATION_REQUEST,
-    RACE_CUSTOMIZATION_RESPONSE;
+    RACE_CUSTOMIZATION_RESPONSE,
+
+    SERVER_REGISTRATION, ROOM_CODE_REQUEST, LOBBY_REQUEST;
 
     public static PacketType assignPacketType(int packetType, byte[] payload){
         switch(packetType){
@@ -65,6 +67,10 @@ public enum PacketType {
                 return RACE_CUSTOMIZATION_REQUEST;
             case 104:
                 return RACE_CUSTOMIZATION_RESPONSE;
+            case 201:
+                return SERVER_REGISTRATION;
+            case 202:
+                return ROOM_CODE_REQUEST;
             default:
         }
         return OTHER;

src/main/java/seng302/serverRepository/ReadableByteInputStream.java

@@ -0,0 +1,34 @@
+package seng302.serverRepository;
+
+import java.io.InputStream;
+
+public class ReadableByteInputStream {
+    private InputStream is;
+
+    public ReadableByteInputStream(InputStream is){
+        this.is = is;
+    }
+
+    public byte[] getBytes(int n) throws Exception {
+        byte[] bytes = new byte[n];
+        for (int i = 0; i < n; i++) {
+            bytes[i] = (byte) readByte();
+        }
+        return bytes;
+    }
+
+    public void skipBytes(long n) throws Exception {
+        for (int i = 0; i < n; i++) {
+            readByte();
+        }
+    }
+
+    public int readByte() throws Exception {
+        int currentByte = is.read();
+
+        if (currentByte == -1) {
+            throw new Exception();
+        }
+        return currentByte;
+    }
+}

src/main/java/seng302/serverRepository/ServerListing.java

@@ -0,0 +1,109 @@
+package seng302.serverRepository;
+
+public class ServerListing {
+    private static final int SERVER_TTL_DEFAULT = 10;
+
+    private String serverName = "";
+    private String mapName = "";
+    private String address = "";
+    private int portNumber = 0;
+    private int capacity = 0;
+    private int players = 0;
+    private String roomCode = "";
+    private int ttl = SERVER_TTL_DEFAULT;
+
+
+    public ServerListing(String serverName, String mapName, String address, int portNumber, int capacity){
+        this.serverName = serverName;
+        this.mapName = mapName;
+        this.address = address;
+        this.portNumber = portNumber;
+        this.capacity = capacity;
+    }
+
+    public ServerListing setNumberOfPlayers(int players){
+        this.players = players;
+        return this;
+    }
+
+    public ServerListing setRoomCode(String roomCode){
+        this.roomCode = roomCode;
+        return this;
+    }
+
+    public void refreshTtl(){
+        ttl = SERVER_TTL_DEFAULT;
+    }
+
+    public void decrementTtl(){
+        ttl--;
+    }
+
+    public boolean hasTtlExpired(){
+        return ttl < 0;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == null) {
+            return false;
+        }
+        if (!ServerListing.class.isAssignableFrom(obj.getClass())) {
+            return false;
+        }
+
+        final ServerListing other = (ServerListing) obj;
+
+        if (this.getPortNumber() != other.getPortNumber()){
+            return false;
+        }
+
+        if (!this.getMapName().equals(other.getMapName())){
+            return false;
+        }
+
+        if (!this.getServerName().equals(other.getServerName())){
+            return false;
+        }
+
+        if (this.getCapacity() != other.getCapacity()){
+            return false;
+        }
+
+        if (!this.getAddress().equals(other.getAddress())){
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return this.getServerName().hashCode() +
+                this.getAddress().hashCode() + this.getMapName().hashCode();
+    }
+
+    public String getRoomCode() {
+        return roomCode;
+    }
+
+    public int getPortNumber() {
+        return portNumber;
+    }
+
+    public String getMapName() {
+        return mapName;
+    }
+
+    public String getServerName() {
+        return serverName;
+    }
+
+    public int getCapacity() {
+        return capacity;
+    }
+
+    public String getAddress() {
+        return address;
+    }
+}

src/main/java/seng302/serverRepository/ServerRepoStreamParser.java

@@ -0,0 +1,109 @@
+package seng302.serverRepository;
+
+
+import seng302.gameServer.messages.Message;
+import seng302.model.stream.packets.PacketType;
+
+import java.io.InputStream;
+import java.util.Arrays;
+
+public class ServerRepoStreamParser {
+    private ReadableByteInputStream inputStream;
+
+    private String roomCode;
+    private String mapName;
+    private ServerListing serverListing;
+
+    public ServerRepoStreamParser(InputStream is){
+        inputStream = new ReadableByteInputStream(is);
+    }
+
+    public PacketType parse() throws Exception {
+        int sync1 = inputStream.readByte();
+        int sync2 = inputStream.readByte();
+
+        PacketType packetType = null;
+
+        if (sync1 == 0x47 && sync2 == 0x83) {
+            int type = inputStream.readByte();
+            inputStream.skipBytes(10);
+            long payloadLength = Message.bytesToLong(inputStream.getBytes(2));
+            byte[] payload = inputStream.getBytes((int) payloadLength);
+            inputStream.skipBytes(4);
+
+            packetType = PacketType.assignPacketType(type, payload);
+
+            switch (packetType) {
+                case ROOM_CODE_REQUEST:
+                    roomCode = parseRoomCodeRequest(payload);
+                    break;
+
+                case LOBBY_REQUEST:
+                    mapName = parseLobbyRequest(payload);
+
+                case SERVER_REGISTRATION:
+                    serverListing = parseServerRegistration(payload);
+                    break;
+            }
+
+        }
+
+        return packetType;
+    }
+    private String parseLobbyRequest(byte[] payload) {
+        int mapNameLength = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 0 ,4));
+
+        return new String(Arrays.copyOfRange(payload, 4, 4+mapNameLength));
+    }
+
+    private String parseRoomCodeRequest(byte[] payload) {
+        int roomCodeLength = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 0 ,4));
+
+        return new String(Arrays.copyOfRange(payload, 4, 4+roomCodeLength));
+    }
+
+    public static ServerListing parseServerRegistration(byte[] payload) {
+        int nameLength = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 0, 6));
+        int mapNameLength = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 6, 12));
+        int addressLength = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 12, 18));
+        int roomCodeLength = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 18, 24));
+
+        int portNumber = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 24, 28));
+        int players = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 28, 32));
+        int capacity = (int) Message.bytesToLong(Arrays.copyOfRange(payload, 32, 36));
+
+        int currentPos = 36;
+        int nextPos = currentPos + nameLength;
+        String serverName = new String(Arrays.copyOfRange(payload, currentPos, nextPos));
+
+        currentPos = nextPos;
+        nextPos = currentPos + mapNameLength;
+        String mapName = new String(Arrays.copyOfRange(payload, currentPos, nextPos));
+
+        currentPos = nextPos;
+        nextPos = currentPos + addressLength;
+        String address = new String(Arrays.copyOfRange(payload, currentPos, nextPos));
+
+        currentPos = nextPos;
+        nextPos = currentPos + roomCodeLength;
+        String roomCode = new String(Arrays.copyOfRange(payload, currentPos, nextPos));
+
+        ServerListing serverListing = new ServerListing(serverName, mapName, address, portNumber, capacity);
+        serverListing.setNumberOfPlayers(players);
+        serverListing.setRoomCode(roomCode);
+
+        return serverListing;
+    }
+
+    public String getRoomCode() {
+        return roomCode;
+    }
+
+    public String getMapName() {
+        return mapName;
+    }
+
+    public ServerListing getServerListing() {
+        return serverListing;
+    }
+}

src/main/java/seng302/serverRepository/ServerRepository.java

@@ -0,0 +1,83 @@
+package seng302.serverRepository;
+
+import seng302.gameServer.messages.Message;
+import seng302.gameServer.messages.RoomCodeRequest;
+import seng302.gameServer.messages.ServerRegistrationMessage;
+import seng302.model.stream.packets.PacketType;
+
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.util.Timer;
+import java.util.TimerTask;
+
+public class ServerRepository {
+    private ServerTable serverTable;
+
+    public ServerRepository() throws Exception {
+        System.out.println(" -- Starting Server Repository -- ");
+        serverTable = new ServerTable();
+
+        ServerSocket serverSocket = new ServerSocket(9999);
+
+
+        // TODO Remove later, this is for testing
+        new Timer().schedule(new TimerTask() {
+            @Override
+            public void run() {
+                try {
+                    new ServerRepositoryClient();
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+            }
+        }, 5000);
+
+        while (true){
+            Socket clientSocket = serverSocket.accept();
+
+            parseRequest(clientSocket);
+
+            clientSocket.close();
+        }
+    }
+
+
+    private void parseRequest(Socket clientSocket) throws Exception {
+        ServerRepoStreamParser parser = new ServerRepoStreamParser(clientSocket.getInputStream());
+
+        if (clientSocket.isConnected() && !clientSocket.isClosed()){
+            PacketType parsePacketResult = parser.parse();
+
+            switch (parsePacketResult){
+                case SERVER_REGISTRATION:
+                    ServerListing listing = parser.getServerListing();
+
+                    if (!serverTable.getAllServers().contains(listing)){
+                        listing.setRoomCode(serverTable.getNextRoomCode().toString());
+                    }
+
+                    serverTable.addServer(listing);
+
+                    Message serverRegMessage = new RoomCodeRequest(listing.getRoomCode());
+                    clientSocket.getOutputStream().write(serverRegMessage.getBuffer());
+                    break;
+
+                case ROOM_CODE_REQUEST:
+                    String desiredRoomCode = parser.getRoomCode();
+
+                    ServerListing serverListing = serverTable.getServerByRoomCode(desiredRoomCode);
+                    Message response;
+
+                    if (serverListing != null){
+                        response = new ServerRegistrationMessage(serverListing.getServerName(), serverListing.getMapName(), serverListing.getAddress(), serverListing.getPortNumber(), 0, 0, desiredRoomCode);
+                    }
+                    else{
+                        response = new ServerRegistrationMessage("", "", "", 0, 0, 0, "");
+                    }
+
+                    clientSocket.getOutputStream().write(response.getBuffer());
+                    break;
+            }
+        }
+    }
+}

src/main/java/seng302/serverRepository/ServerRepositoryClient.java

@@ -0,0 +1,54 @@
+package seng302.serverRepository;
+
+import com.sun.xml.internal.ws.api.message.Packet;
+import seng302.gameServer.messages.Message;
+import seng302.gameServer.messages.ServerRegistrationMessage;
+import seng302.model.stream.packets.PacketType;
+
+import java.io.IOException;
+import java.net.Socket;
+import java.util.Timer;
+import java.util.TimerTask;
+
+public class ServerRepositoryClient {
+
+    private String roomCode = "0";
+
+    public ServerRepositoryClient() throws Exception {
+        new Timer().schedule(new TimerTask() {
+            @Override
+            public void run() {
+                try {
+                    sendUpdate();
+                } catch (Exception e) {
+                    e.printStackTrace();
+                }
+            }
+        }, 0, 5000);
+    }
+
+    private void sendUpdate() throws Exception {
+        Socket socket = new Socket("localhost", 9999);
+        ServerRepoStreamParser parser = new ServerRepoStreamParser(socket.getInputStream());
+        Message req = new ServerRegistrationMessage("asdf", "Asdf", "asdf", 6969, 1, 20, "4949");
+
+        socket.getOutputStream().write(req.getBuffer());
+
+        PacketType packetType = parser.parse();
+
+        if (packetType != PacketType.ROOM_CODE_REQUEST){
+            return;
+        }
+
+        String roomCode = parser.getRoomCode();
+
+        if (roomCode.equals("0")){
+            return;
+        }
+
+        this.roomCode = roomCode;
+
+        socket.close();
+    }
+}
+

src/main/java/seng302/serverRepository/ServerTable.java

@@ -0,0 +1,79 @@
+package seng302.serverRepository;
+
+import com.sun.corba.se.spi.activation.Server;
+
+import java.util.*;
+
+public class ServerTable {
+    private List<ServerListing> servers;
+    private int lastRoomCode = 4020;
+
+    public ServerTable(){
+        servers = new ArrayList<>();
+
+        new Timer().schedule(new TimerTask() {
+            @Override
+            public void run() {
+                updateServers();
+            }
+        }, 0, 1000);
+
+    }
+
+    private void updateServers() {
+        List<ServerListing> serversToRemove = new ArrayList<>();
+
+        for (ServerListing server : servers){
+            server.decrementTtl();
+
+            if (server.hasTtlExpired()){
+                serversToRemove.add(server);
+            }
+        }
+
+        for (ServerListing server : serversToRemove){
+            System.out.println("Removing " + server.getServerName());
+            servers.remove(server);
+        }
+    }
+
+    public void addServer(ServerListing server){
+        if (servers.contains(server)){
+           updateTtlForServer(server);
+           return;
+        }
+
+        servers.add(server);
+    }
+
+    private void updateTtlForServer(ServerListing server) {
+        for (ServerListing serverListing : servers){
+            if (server.equals(serverListing)){
+                System.out.println("Refreshing TTL For "  + server.getServerName());
+                serverListing.refreshTtl();
+            }
+        }
+    }
+
+    public List<ServerListing> getAllServers(){
+        return Collections.unmodifiableList(servers);
+    }
+
+    public ServerListing getServerByRoomCode(String roomCode){
+        for (ServerListing serverListing : servers){
+            if (serverListing.getRoomCode().equals(roomCode)){
+                return serverListing;
+            }
+        }
+
+        return null;
+    }
+
+    public Integer getNextRoomCode(){
+        System.out.println(lastRoomCode);
+        lastRoomCode += 1;
+        return lastRoomCode;
+    }
+
+
+}

src/main/java/seng302/visualiser/ServerListener.java

@@ -6,11 +6,10 @@ import seng302.gameServer.ServerDescription;
 import javax.jmdns.JmDNS;
 import javax.jmdns.ServiceEvent;
 import javax.jmdns.ServiceListener;
+import javax.jmdns.impl.JmDNSImpl;
 import java.io.IOException;
 import java.net.InetAddress;
-import java.util.ArrayList;
+import java.util.*;
-import java.util.HashSet;
-import java.util.Set;
 
 import static seng302.gameServer.ServerAdvertiser.getLocalHostIp;
 
@@ -18,6 +17,7 @@ import static seng302.gameServer.ServerAdvertiser.getLocalHostIp;
  * Listens for servers on the local network
  */
 public class ServerListener{
+    private static Integer SERVICE_REFRESH_INTERVAL = 5 * 1000;
     private static ServerListener instance;
     private ServerListenerDelegate delegate;
     private JmDNS jmdns = null;
@@ -91,8 +91,16 @@ public class ServerListener{
 
     private ServerListener() throws IOException {
         jmdns = JmDNS.create(InetAddress.getByName(getLocalHostIp()));
+
         listener = new GameServeMonitor();
         jmdns.addServiceListener(ServerAdvertiser.SERVICE_TYPE, listener);
+
+        /*new Timer().schedule(new TimerTask() {
+            @Override
+            public void run() {
+                refresh();
+            }
+        }, 50, SERVICE_REFRESH_INTERVAL);*/
     }
 
     public static ServerListener getInstance() throws IOException {
@@ -110,4 +118,25 @@ public class ServerListener{
     public void setDelegate(ServerListenerDelegate delegate){
         this.delegate = delegate;
     }
+
+    public void refresh(){
+        ArrayList<ServerDescription> servers = new ArrayList<>(listener.servers);
+
+        for (ServerDescription serverDescription : servers){
+            if (serverDescription.hasExpired()){
+                jmdns.requestServiceInfo(ServerAdvertiser.SERVICE_TYPE, serverDescription.getName());
+            }
+            else{
+                serverDescription.hasBeenRefreshed();
+            }
+        }
+
+        for (ServerDescription server : servers){
+            if (server.serverShouldBeRemoved()){
+                listener.servers.remove(server);
+                delegate.serverRemoved(new ArrayList<ServerDescription>(listener.servers));
+            }
+        }
+
+    }
 }