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

@@ -6,6 +6,9 @@ import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.check_nick.CheckUsern
 import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.login.LoginHandler;
 import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.login.LoginParser;
 import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.login.LoginRequest;
+import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.logout.LogoutHandler;
+import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.logout.LogoutParser;
+import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.logout.LogoutRequest;
 import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.ping.PingHandler;
 import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.ping.PingParser;
 import ch.unibas.dmi.dbis.cs108.casono.server.app.commands.ping.PingRequest;
@@ -98,5 +101,9 @@ public class ServerApp {
         parserDispatcher.register("LOGIN", new LoginParser());
         commandRouter.register(
                 LoginRequest.class, new LoginHandler(responseDispatcher, userRegistry));
+
+        parserDispatcher.register("LOGOUT", new LogoutParser());
+        commandRouter.register(
+                LogoutRequest.class, new LogoutHandler(responseDispatcher, userRegistry));
     }
 }

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/logout/LogoutHandler.java

@@ -0,0 +1,45 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.logout;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.domain.user.UserRegistry;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandHandler;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.ErrorResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.OkResponse;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher.ResponseDispatcher;
+
+/** Handles {@link LogoutRequest} to logout connected user. */
+public class LogoutHandler implements CommandHandler<LogoutRequest> {
+    private final ResponseDispatcher responseDispatcher;
+    private final UserRegistry userRegistry;
+
+    /**
+     * Creates a new logout handler to logout user.
+     *
+     * @param responseDispatcher dispatcher used to send the logout result back to the client
+     * @param userRegistry registry responsible for tracking connected user sessions
+     */
+    public LogoutHandler(ResponseDispatcher responseDispatcher, UserRegistry userRegistry) {
+        this.responseDispatcher = responseDispatcher;
+        this.userRegistry = userRegistry;
+    }
+
+    /**
+     * Executes the logout request for the given request.
+     *
+     * <p>The user is removed from the {@link UserRegistry}.
+     *
+     * @param request the request to execute
+     */
+    @Override
+    public void execute(LogoutRequest request) {
+        boolean wasRemoved = userRegistry.removeBySessionId(request.getSessionId());
+        if (wasRemoved) {
+            responseDispatcher.dispatch(new OkResponse(request.getContext()));
+        } else {
+            responseDispatcher.dispatch(
+                    new ErrorResponse(
+                            request.getContext(),
+                            "NO_USER_ASSOCIATED",
+                            "No user is associated with your session. Did you login before?"));
+        }
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/logout/LogoutParser.java

@@ -0,0 +1,19 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.logout;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.CommandParser;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.PrimitiveRequest;
+
+/** Parses a primitive request into a {@link LogoutRequest}. */
+public class LogoutParser implements CommandParser<LogoutRequest> {
+
+    /**
+     * Parses a primitive request into a LogoutRequest.
+     *
+     * @param primitiveRequest the request to parse
+     * @return the created {@link LogoutRequest}
+     */
+    @Override
+    public LogoutRequest parse(PrimitiveRequest primitiveRequest) {
+        return new LogoutRequest(primitiveRequest.context());
+    }
+}

src/main/java/ch/unibas/dmi/dbis/cs108/casono/server/app/commands/logout/LogoutRequest.java

@@ -0,0 +1,18 @@
+package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.logout;
+
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Request;
+import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
+
+/** Request implementation used to logout a currently logged in user */
+public class LogoutRequest extends Request {
+
+    /**
+     * Constructs a new LogoutRequest with the given context.
+     *
+     * @param context the {@link RequestContext} containing information for responding to the
+     *     request
+     */
+    public LogoutRequest(RequestContext context) {
+        super(context);
+    }
+}