src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/ServerApp.java

@@ -7,6 +7,7 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.command.CommandRouter;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.DisconnectEvent;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.events.EventBus;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.CommandParserDispatcher;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionDisconnectJob;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.sessions.SessionManager;
 import java.time.Duration;
 import java.util.concurrent.Executors;
@@ -17,9 +18,12 @@ import org.apache.logging.log4j.Logger;
 
 /** Application class for starting the server. */
 public class ServerApp {
-    public static final int USER_CLEANUP_JOB_DELAY = 0;
+    private static final int USER_CLEANUP_JOB_DELAY = 0;
-    public static final int USER_CLEANUP_JOB_PERIOD = 10;
+    private static final int USER_CLEANUP_JOB_PERIOD = 10;
-    public static final int USER_CLEANUP_JOB_RECONNECT_THRESHOLD = 10;
+    private static final int USER_CLEANUP_JOB_RECONNECT_THRESHOLD = 10;
+    private static final int SESSION_DISCONNECT_JOB_DELAY = 0;
+    private static final int SESSION_DISCONNECT_JOB_PERIOD = 2;
+    private static final int SESSION_DISCONNECT_JOB_TIMEOUT = 5;
 
     public static void start(String arg) {
         int port = Integer.parseInt(arg);
@@ -45,6 +49,14 @@ public class ServerApp {
                 USER_CLEANUP_JOB_DELAY,
                 USER_CLEANUP_JOB_PERIOD,
                 TimeUnit.SECONDS);
+        scheduler.scheduleAtFixedRate(
+                new SessionDisconnectJob(
+                        sessionManager,
+                        eventBus,
+                        Duration.ofSeconds(SESSION_DISCONNECT_JOB_TIMEOUT)),
+                SESSION_DISCONNECT_JOB_DELAY,
+                SESSION_DISCONNECT_JOB_PERIOD,
+                TimeUnit.SECONDS);
 
         networkManager.start();
     }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/Session.java

@@ -6,12 +6,14 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.CommandParserDispat
 import ch.unibas.dmi.dbis.cs108.casono.server.network.response.PrimitiveResponse;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.transport.TransportLayer;
 import java.io.IOException;
+import java.time.Instant;
 import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
 
 /** Represents a client session in the network server. */
 public class Session {
     private final SessionId id;
+    private Instant lastActivity;
     private final TransportLayer transport;
     private final BlockingQueue<PrimitiveResponse> responseQueue;
     private final CommandParserDispatcher dispatcher;
@@ -31,6 +33,7 @@ public class Session {
             CommandParserDispatcher dispatcher,
             CommandRouter router) {
         this.id = new SessionId();
+        this.lastActivity = Instant.now();
         this.transport = transport;
         this.dispatcher = dispatcher;
         this.router = router;
@@ -46,6 +49,20 @@ public class Session {
         return this.id;
     }
 
+    /**
+     * Gets the timestamp of the last inbound activity for this session.
+     *
+     * @return an {@link Instant} representing the time of the last inbound activity
+     */
+    public Instant getLastInboundActivity() {
+        return lastActivity;
+    }
+
+    /** Updates the timestamp of the last inbound activity for this session. */
+    public void updateLastInboundActivity() {
+        this.lastActivity = Instant.now();
+    }
+
     /**
      * Returns the TransportLayer of this session
      *

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/SessionDisconnectJob.java

@@ -0,0 +1,40 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.network.sessions;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.events.DisconnectEvent;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.events.EventBus;
+import java.time.Duration;
+import java.time.Instant;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+public class SessionDisconnectJob implements Runnable {
+    private final Logger logger;
+    private final SessionManager sessionManager;
+    private final EventBus eventBus;
+    private final Duration timeoutThreshold;
+
+    public SessionDisconnectJob(
+            SessionManager sessionManager, EventBus eventBus, Duration timeoutThreshold) {
+        this.logger = LogManager.getLogger(SessionDisconnectJob.class);
+        this.sessionManager = sessionManager;
+        this.eventBus = eventBus;
+        this.timeoutThreshold = timeoutThreshold;
+    }
+
+    @Override
+    public void run() {
+        logger.debug("Job started.");
+        Instant threshold = Instant.now().minus(timeoutThreshold);
+
+        for (Session session : sessionManager.getAllSessions()) {
+            if (session.getLastInboundActivity().isBefore(threshold)) {
+                eventBus.publish(new DisconnectEvent(session.getId()));
+                logger.info(
+                        "Initiated disconnect of {}, as it hasn't been active since a while",
+                        session.getId());
+            }
+        }
+
+        logger.debug("Job finished.");
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/SessionManager.java

@@ -6,8 +6,10 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.events.EventBus;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.parser.CommandParserDispatcher;
 import ch.unibas.dmi.dbis.cs108.casono.server.network.transport.TransportLayer;
 import java.io.IOException;
+import java.util.Collection;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.stream.Collectors;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 
@@ -109,4 +111,8 @@ public class SessionManager {
 
         return handle.session();
     }
+
+    public Collection<Session> getAllSessions() {
+        return sessions.values().stream().map(SessionHandle::session).collect(Collectors.toList());
+    }
 }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/network/sessions/SessionReader.java

@@ -43,6 +43,7 @@ public class SessionReader implements Runnable {
             RawPacket rawPacket = null;
             try {
                 rawPacket = transport.read();
+                session.updateLastInboundActivity();
                 logger.debug("Recieved: {}", rawPacket);
 
                 RawRequest rawRequest = ProtocolParser.parse(rawPacket.payload());