Merge pull request #316 from thiccaxe/server-list-ping-update

Updated Server List Ping

src/main/java/net/minestom/server/event/server/ClientPingServerEvent.java

@@ -0,0 +1,128 @@
+package net.minestom.server.event.server;
+
+import net.minestom.server.event.CancellableEvent;
+import net.minestom.server.event.Event;
+import net.minestom.server.network.player.PlayerConnection;
+import net.minestom.server.utils.time.TimeUnit;
+import net.minestom.server.utils.time.UpdateOption;
+import org.jetbrains.annotations.NotNull;
+
+
+/**
+ * Called when a {@link PlayerConnection} sends a ping packet,
+ * usually after the status packet. Only used in versions since the netty rewrite; 1.7+
+ *
+ * @see ServerListPingEvent
+ */
+public class ClientPingServerEvent extends Event implements CancellableEvent {
+    private static final UpdateOption DEFAULT_DELAY = new UpdateOption(0, TimeUnit.MILLISECOND);
+
+    private final PlayerConnection connection;
+    private long payload;
+
+    private boolean cancelled = false;
+    private UpdateOption delay;
+
+    /**
+     * Creates a new client ping server event with 0 delay
+     *
+     * @param connection the player connection
+     * @param payload the payload the client sent
+     */
+    public ClientPingServerEvent(@NotNull PlayerConnection connection, long payload) {
+        this.connection = connection;
+        this.payload = payload;
+        this.delay = DEFAULT_DELAY;
+    }
+
+    /**
+     * Creates a new client ping server event with 0 delay
+     *
+     * @param connection the player connection
+     * @param payload the payload the client sent
+     */
+    public ClientPingServerEvent(@NotNull PlayerConnection connection, long payload, UpdateOption delay) {
+        this.connection = connection;
+        this.payload = payload;
+        this.delay = delay;
+    }
+
+
+    /**
+     * PlayerConnection of received packet. Note that the player has not joined the server
+     * at this time.
+     *
+     * @return the connection.
+     */
+    public @NotNull PlayerConnection getConnection() {
+        return connection;
+    }
+
+    /**
+     * Payload of received packet. May be any number; vanilla uses a system dependant time value.
+     *
+     * @return the payload
+     */
+    public long getPayload() {
+        return payload;
+    }
+
+    /**
+     * Sets the payload to respond with.
+     *
+     * Note: This should be the same as the client sent, however vanilla 1.17 seems to be OK with a different payload.
+     * @param payload the payload
+     */
+    public void setPayload(long payload) {
+        this.payload = payload;
+    }
+
+    /**
+     * Gets the delay until minestom will send the ping response packet.
+     *
+     * @return the delay
+     */
+    public @NotNull UpdateOption getDelay() {
+        return delay;
+    }
+
+    /**
+     * Adds to the delay until minestom will send the ping response packet.
+     *
+     * @param delay the delay
+     */
+    public void addDelay(@NotNull UpdateOption delay) {
+        this.delay = new UpdateOption(this.delay.toMilliseconds() + delay.toMilliseconds(), TimeUnit.MILLISECOND);
+    }
+
+    /**
+     * Sets the delay until minestom will send the ping response packet.
+     *
+     * @param delay the delay
+     */
+    public void setDelay(@NotNull UpdateOption delay) {
+        this.delay = delay;
+    }
+
+    /**
+     * Clears the delay until minestom will send the ping response packet.
+     */
+    public void noDelay() {
+        this.delay = DEFAULT_DELAY;
+    }
+
+    @Override
+    public boolean isCancelled() {
+        return cancelled;
+    }
+
+    /**
+     * Cancelling this event will cause the server to appear offline in the vanilla server list.
+     *
+     * @param cancel true if the event should be cancelled, false otherwise
+     */
+    @Override
+    public void setCancelled(boolean cancel) {
+        this.cancelled = cancel;
+    }
+}

src/main/java/net/minestom/server/network/packet/client/status/PingPacket.java

@@ -1,5 +1,8 @@
 package net.minestom.server.network.packet.client.status;
 
+import net.kyori.adventure.text.Component;
+import net.minestom.server.MinecraftServer;
+import net.minestom.server.event.server.ClientPingServerEvent;
 import net.minestom.server.network.packet.client.ClientPreplayPacket;
 import net.minestom.server.network.packet.server.status.PongPacket;
 import net.minestom.server.network.player.PlayerConnection;
@@ -15,9 +18,22 @@ public class PingPacket implements ClientPreplayPacket {
 
     @Override
     public void process(@NotNull PlayerConnection connection) {
-        PongPacket pongPacket = new PongPacket(number);
+        final ClientPingServerEvent clientPingEvent = new ClientPingServerEvent(connection, number);
-        connection.sendPacket(pongPacket);
+        MinecraftServer.getGlobalEventHandler().callEvent(ClientPingServerEvent.class, clientPingEvent);
-        connection.disconnect();
+
+        if (clientPingEvent.isCancelled()) {
+            connection.disconnect();
+        } else {
+            if (clientPingEvent.getDelay().toMilliseconds() == 0) {
+                connection.sendPacket(new PongPacket(clientPingEvent.getPayload()));
+                connection.disconnect();
+            } else {
+                MinecraftServer.getSchedulerManager().buildTask(() -> {
+                    connection.sendPacket(new PongPacket(clientPingEvent.getPayload()));
+                    connection.disconnect();
+                }).delay(clientPingEvent.getDelay()).schedule();
+            }
+        }
     }
 
     @Override

src/main/java/net/minestom/server/ping/ResponseData.java

@@ -29,6 +29,7 @@ public class ResponseData {
     private int online;
     private Component description;
     private String favicon;
+    private boolean playersHidden;
 
     /**
      * Constructs a new {@link ResponseData}.
@@ -41,6 +42,7 @@ public class ResponseData {
         this.maxPlayer = this.online + 1;
         this.description = DEFAULT_DESCRIPTION;
         this.favicon = "";
+        this.playersHidden = false;
     }
 
     /**
@@ -294,6 +296,25 @@ public class ResponseData {
         return this.entries;
     }
 
+    /**
+     * Sets whether the players are hidden or not.
+     * In the vanilla client, `???` will be displayed where the online and maximum players would be.
+     *
+     * @param playersHidden if the players are hidden
+     */
+    public void setPlayersHidden(boolean playersHidden) {
+        this.playersHidden = playersHidden;
+    }
+
+    /**
+     * Returns if the players are hidden or not.
+     *
+     * @return if the players are hidden
+     */
+    public boolean arePlayersHidden() {
+        return playersHidden;
+    }
+
     /**
      * Converts the response data into a {@link JsonObject}.
      *

src/main/java/net/minestom/server/ping/ServerListPingType.java

@@ -109,22 +109,25 @@ public enum ServerListPingType {
         versionObject.addProperty("name", data.getVersion());
         versionObject.addProperty("protocol", data.getProtocol());
 
-        // players info
+        JsonObject playersObject = null;
-        final JsonObject playersObject = new JsonObject();
+        if (!data.arePlayersHidden()) {
-        playersObject.addProperty("max", data.getMaxPlayer());
+            // players info
-        playersObject.addProperty("online", data.getOnline());
+            playersObject = new JsonObject();
+            playersObject.addProperty("max", data.getMaxPlayer());
+            playersObject.addProperty("online", data.getOnline());
 
-        // individual players
+            // individual players
-        final JsonArray sampleArray = new JsonArray();
+            final JsonArray sampleArray = new JsonArray();
-        for (NamedAndIdentified entry : data.getEntries()) {
+            for (NamedAndIdentified entry : data.getEntries()) {
-            JsonObject playerObject = new JsonObject();
+                JsonObject playerObject = new JsonObject();
-            playerObject.addProperty("name", SECTION.serialize(entry.getName()));
+                playerObject.addProperty("name", SECTION.serialize(entry.getName()));
-            playerObject.addProperty("id", entry.getUuid().toString());
+                playerObject.addProperty("id", entry.getUuid().toString());
-            sampleArray.add(playerObject);
+                sampleArray.add(playerObject);
+            }
+
+            playersObject.add("sample", sampleArray);
         }
 
-        playersObject.add("sample", sampleArray);
-
         final JsonObject jsonObject = new JsonObject();
         jsonObject.add("version", versionObject);
         jsonObject.add("players", playersObject);

src/test/java/demo/Main.java

@@ -6,6 +6,7 @@ import demo.blocks.UpdatableBlockDemo;
 import demo.commands.*;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.format.NamedTextColor;
+import net.kyori.adventure.text.format.Style;
 import net.kyori.adventure.text.format.TextColor;
 import net.kyori.adventure.text.format.TextDecoration;
 import net.minestom.server.MinecraftServer;
@@ -86,6 +87,9 @@ public class Main {
                         .append(Component.text(" VERSION: ", NamedTextColor.GRAY))
                         .append(Component.text(event.getConnection().getProtocolVersion()))));
             }
+            responseData.addEntry(NamedAndIdentified.named(Component.text("Time", NamedTextColor.YELLOW)
+                    .append(Component.text(": ", NamedTextColor.GRAY))
+                    .append(Component.text(System.currentTimeMillis(), Style.style(TextDecoration.ITALIC)))));
 
             // components will be converted the legacy section sign format so they are displayed in the client
             responseData.addEntry(NamedAndIdentified.named(Component.text("You can use ").append(Component.text("styling too!", NamedTextColor.RED, TextDecoration.BOLD))));
@@ -93,6 +97,7 @@ public class Main {
             // the data will be automatically converted to the correct format on response, so you can do RGB and it'll be downsampled!
             // on legacy versions, colors will be converted to the section format so it'll work there too
             responseData.setDescription(Component.text("This is a Minestom Server", TextColor.color(0x66b3ff)));
+            //responseData.setPlayersHidden(true);
         });
 
         PlayerInit.init();