Feat/94 add get lobby list command on server side #261

Merged
jona.walpert merged 4 commits from feat/94-add-get-lobby-list-command-on-server-side into main 2026-04-11 21:29:07 +02:00
10 changed files with 176 additions and 58 deletions
@@ -50,6 +50,12 @@ This document describes the protocol for client-server communication in our appl
- [Error Response](#error-response-6)
- [Example Request](#example-request-4)
- [Example Response](#example-response-4)
- [GET_LOBBY_LIST command](#get_lobby_list-command)
- [Required pre-execution checks](#required-pre-execution-checks)
- [Request Parameters](#request-parameters)
- [Success Response](#success-response)
- [Example Request](#example-request)
- [Example Response](#example-response)
- [SEND_MESSAGE command](#send_message-command)
- [Required pre-execution checks](#required-pre-execution-checks)
- [Request Parameters](#request-parameters)
@@ -535,6 +541,60 @@ END
END
```
## GET_LOBBY_LIST command
The `GET_LOBBY_LIST` command requests the server to return a list of currently available lobbies with basic metadata.
### Required pre-execution checks
None.
### Request Parameters
No parameters.
### Implementation notes
- Parser: `GetLobbyListParser` — creates `GetLobbyListRequest` (no parameters).
- Handler: `GetLobbyListHandler` — queries `LobbyManager#getAllLobbies()` and returns `GetLobbyListResponse`.
- Response: `GetLobbyListResponse` — builds a `LOBBIES` collection with repeated `LOBBY` blocks containing `ID`, `NAME`, `PLAYER_COUNT`.
### Success Response
The response contains a `LOBBIES` collection with nested `LOBBY` entries.
Example response structure:
```
+OK
LOBBIES
LOBBY
ID=1
NAME=Room 1
PLAYER_COUNT=2
END
LOBBY
ID=2
NAME=Room 2
PLAYER_COUNT=3
END
END
END
```
### Example Request
```
GET_LOBBY_LIST
```
### Example Response (error)
```
-ERR
CODE=NO_LOBBIES_AVAILABLE
MESSAGE=No lobbies available
END
```
## GET_LOBBY_STATUS command
The `GET_LOBBY_STATUS` command requests the server to return the current state of a lobby, including the list of players and their ready state.
@@ -140,7 +140,21 @@ public class ServerApp {
commandRouter.register(
ListUsersRequest.class, new ListUsersHandler(responseDispatcher, userRegistry));
// GET_LOBBY_STATUS registration
// GET_LOBBY_LIST registration
parserDispatcher.register(
"GET_LOBBY_LIST",
new ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list
.GetLobbyListParser());
commandRouter.register(
ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list
.GetLobbyListRequest.class,
(ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandHandler<
ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby
.get_lobby_list.GetLobbyListRequest>)
new ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list
.GetLobbyListHandler(responseDispatcher, lobbyManager));
// GET_LOBBY_STATUS registration
parserDispatcher.register(
"GET_LOBBY_STATUS",
new ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_status
@@ -155,6 +169,7 @@ public class ServerApp {
.get_lobby_status.GetLobbyStatusHandler(
responseDispatcher, lobbyManager, userRegistry));
// JOIN_LOBBY registration
parserDispatcher.register(
"JOIN_LOBBY",
@@ -0,0 +1,28 @@
package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list;
import ch.unibas.dmi.dbis.cs108.casono.server.domain.lobby.LobbyManager;
import ch.unibas.dmi.dbis.cs108.casono.server.network.command.execution.CommandHandler;
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher.ResponseDispatcher;
import java.util.Collection;
/**
* Handler for the `GET_LOBBY_LIST` command.
*
* <p>Queries the {@link LobbyManager} for all available lobbies and dispatches a {@link
* GetLobbyListResponse} containing basic metadata for each lobby (`ID`, `NAME`, `PLAYER_COUNT`).
*/
public class GetLobbyListHandler extends CommandHandler<GetLobbyListRequest> {
private final LobbyManager lobbyManager;
public GetLobbyListHandler(ResponseDispatcher responseDispatcher, LobbyManager lobbyManager) {
super(responseDispatcher);
this.lobbyManager = lobbyManager;
}
@Override
public void execute(GetLobbyListRequest request) {
Collection<ch.unibas.dmi.dbis.cs108.casono.server.domain.lobby.Lobby> l =
lobbyManager.getAllLobbies();
responseDispatcher.dispatch(new GetLobbyListResponse(request.getContext(), l));
}
}
@@ -0,0 +1,17 @@
package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list;
import ch.unibas.dmi.dbis.cs108.casono.server.network.command.parsing.CommandParser;
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.PrimitiveRequest;
/**
* Parser for the `GET_LOBBY_LIST` command.
*
* <p>Parses the incoming primitive request and produces a {@link GetLobbyListRequest}. This command
* takes no parameters.
*/
public class GetLobbyListParser implements CommandParser<GetLobbyListRequest> {
@Override
public GetLobbyListRequest parse(PrimitiveRequest primitiveRequest) {
return new GetLobbyListRequest(primitiveRequest.context());
}
}
@@ -0,0 +1,15 @@
package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list;
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 object for the `GET_LOBBY_LIST` command.
*
* <p>Contains only the request context; this command does not require parameters.
*/
public class GetLobbyListRequest extends Request {
public GetLobbyListRequest(RequestContext context) {
super(context);
}
}
@@ -0,0 +1,37 @@
package ch.unibas.dmi.dbis.cs108.casono.server.app.commands.lobby.get_lobby_list;
import ch.unibas.dmi.dbis.cs108.casono.server.domain.lobby.Lobby;
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestContext;
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.SuccessResponse;
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBody;
import java.util.Collection;
/**
* Success response for `GET_LOBBY_LIST`.
*
* <p>Builds a `LOBBIES` collection with repeated `LOBBY` blocks containing `ID`, `NAME` and
* `PLAYER_COUNT`.
*/
public class GetLobbyListResponse extends SuccessResponse {
public GetLobbyListResponse(RequestContext context, Collection<Lobby> lobbies) {
super(
context,
ResponseBody.builder()
.block(
"LOBBIES",
lobbies_block -> {
for (Lobby lobby : lobbies) {
lobbies_block.block(
"LOBBY",
lb -> {
lb.param("ID", lobby.getId().value());
lb.param("NAME", lobby.getName());
lb.param(
"PLAYER_COUNT",
lobby.getPlayerNames().size());
});
}
})
.build());
}
}
@@ -8,14 +8,7 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.ErrorRes
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.dispatcher.ResponseDispatcher;
import java.util.Optional;
/**
* Handler for the `GET_LOBBY_STATUS` command.
*
* <p>Resolves the target lobby either by the optional `ID` parameter or by `USERNAME`. If both are
* omitted the handler requires the session to be associated with a logged-in user (see the inline
* pre-execution check). On success a {@link GetLobbyStatusResponse} is dispatched, otherwise an
* {@link ErrorResponse} with code `LOBBY_NOT_FOUND` is sent.
*/
/** Handler for GET_LOBBY_STATUS: returns lobby details and player list. */
public class GetLobbyStatusHandler extends CommandHandler<GetLobbyStatusRequest> {
private final LobbyManager lobbyManager;
private final UserRegistry userRegistry;
@@ -53,22 +46,10 @@ public class GetLobbyStatusHandler extends CommandHandler<GetLobbyStatusRequest>
@Override
public void execute(GetLobbyStatusRequest request) {
// Resolve username from request or session when no explicit ID/USERNAME
// provided
String targetUsername = request.getUsername();
if (targetUsername == null) {
var maybeUser = userRegistry.getBySessionId(request.getSessionId());
if (maybeUser.isPresent()) {
targetUsername = maybeUser.get().getName();
}
}
var lobby =
(request.getId() != null)
? lobbyManager.getLobby(LobbyId.of(request.getId()))
: (targetUsername != null
? lobbyManager.getLobbyByUsername(targetUsername)
: null);
: lobbyManager.getLobbyByUsername(request.getUsername());
if (lobby == null) {
responseDispatcher.dispatch(
@@ -5,21 +5,6 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.Primitive
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.accessor.RequestParameterAccessor;
public class GetLobbyStatusParser implements CommandParser<GetLobbyStatusRequest> {
/**
* Parse the incoming primitive request into a {@link GetLobbyStatusRequest}.
*
* <p>Supported optional parameters:
*
* <ul>
* <li>`ID` (int) — numeric lobby id to query
* <li>`USERNAME` (String) — username to lookup the lobby for
* </ul>
*
* If both are omitted the handler may require a logged-in session.
*
* @param primitiveRequest raw request containing parameters and context
* @return parsed {@link GetLobbyStatusRequest}
*/
@Override
public GetLobbyStatusRequest parse(PrimitiveRequest primitiveRequest) {
RequestParameterAccessor accessor =
@@ -7,25 +7,16 @@ public class GetLobbyStatusRequest extends Request {
private final Integer id;
private final String username;
/**
* Create a new GetLobbyStatusRequest.
*
* @param context request context (session id, source, etc.)
* @param id optional numeric lobby id to query, or null
* @param username optional username to query the lobby for, or null
*/
public GetLobbyStatusRequest(RequestContext context, Integer id, String username) {
super(context);
this.id = id;
this.username = username;
}
/** Returns the optional lobby id. */
public Integer getId() {
return id;
}
/** Returns the optional username. */
public String getUsername() {
return username;
}
@@ -5,19 +5,8 @@ import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.request.RequestCo
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.SuccessResponse;
import ch.unibas.dmi.dbis.cs108.casono.server.network.protocol.response.builder.ResponseBody;
/**
* Success response for `GET_LOBBY_STATUS`.
*
* <p>Builds a response with a single `LOBBY` block containing `ID`, `NAME` and a nested `PLAYERS`
* collection with repeated `PLAYER` blocks (`USERNAME`, `READY`).
*/
/** Response with lobby player listing and simple READY placeholders. */
public class GetLobbyStatusResponse extends SuccessResponse {
/**
* Create a new response for the provided {@link Lobby}.
*
* @param context request context to use for the response
* @param lobby lobby domain object containing id, name and players
*/
public GetLobbyStatusResponse(RequestContext context, Lobby lobby) {
super(
context,