Add configuration interface to expose certain config values (#12273)

paper-api/src/main/java/io/papermc/paper/configuration/ServerConfiguration.java

@@ -0,0 +1,24 @@
+package io.papermc.paper.configuration;
+
+/**
+ * Represents the configuration settings for a server.
+ * <p>
+ * This interface doesn't aim to cover every possible server configuration
+ * option but focuses on selected critical settings and behaviors.
+ */
+public interface ServerConfiguration {
+
+    /**
+     * Gets whether the server is in online mode.
+     * <p>
+     * This method returns true if:
+     * <ul>
+     * <li>The server is in {@link org.bukkit.Server#getOnlineMode online mode},</li>
+     * <li>Velocity is enabled and configured to be in online mode, or</li>
+     * <li>BungeeCord is enabled and configured to be in online mode.</li>
+     * </ul>
+     *
+     * @return whether the server is in online mode or behind a proxy configured for online mode
+     */
+    boolean isProxyOnlineMode();
+}

paper-api/src/main/java/org/bukkit/Bukkit.java

@@ -14,6 +14,7 @@ import java.util.Set;
 import java.util.UUID;
 import java.util.function.Consumer;
 import java.util.logging.Logger;
+import io.papermc.paper.configuration.ServerConfiguration;
 import net.kyori.adventure.text.Component;
 import org.bukkit.Warning.WarningState;
 import org.bukkit.advancement.Advancement;
@@ -1435,6 +1436,15 @@ public final class Bukkit {
         return server.getOnlineMode();
     }
 
+    /**
+     * Retrieves the server configuration.
+     *
+     * @return the instance of ServerConfiguration containing the server's configuration details
+     */
+    public static @NotNull ServerConfiguration getServerConfig() {
+        return server.getServerConfig();
+    }
+
     /**
      * Gets whether this server allows flying or not.
      *

paper-api/src/main/java/org/bukkit/Server.java

@@ -14,6 +14,7 @@ import java.util.Set;
 import java.util.UUID;
 import java.util.function.Consumer;
 import java.util.logging.Logger;
+import io.papermc.paper.configuration.ServerConfiguration;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.minimessage.MiniMessage;
 import net.kyori.adventure.text.minimessage.tag.resolver.TagResolver;
@@ -1267,6 +1268,13 @@ public interface Server extends PluginMessageRecipient, net.kyori.adventure.audi
      */
     public boolean getOnlineMode();
 
+    /**
+     * Retrieves the server configuration.
+     *
+     * @return the instance of ServerConfiguration containing the server's configuration details
+     */
+    @NotNull ServerConfiguration getServerConfig();
+
     /**
      * Gets whether this server allows flying or not.
      *
@@ -2319,6 +2327,7 @@ public interface Server extends PluginMessageRecipient, net.kyori.adventure.audi
          * @deprecated Server config options may be renamed or removed without notice. Prefer using existing API
          *  wherever possible, rather than directly reading from a server config.
          *
+         * @see #getServerConfig()
          * @return The server's spigot config.
          */
         @Deprecated(since = "1.21.4", forRemoval = true)
@@ -2331,6 +2340,7 @@ public interface Server extends PluginMessageRecipient, net.kyori.adventure.audi
          * @deprecated Server config options may be renamed or removed without notice. Prefer using existing API
          *  wherever possible, rather than directly reading from a server config.
          *
+         * @see #getServerConfig()
          * @return The server's bukkit config.
          */
         // Paper start
@@ -2345,6 +2355,7 @@ public interface Server extends PluginMessageRecipient, net.kyori.adventure.audi
          * @deprecated Server config options may be renamed or removed without notice. Prefer using existing API
          *  wherever possible, rather than directly reading from a server config.
          *
+         * @see #getServerConfig()
          * @return The server's spigot config.
          */
         @Deprecated(since = "1.21.4", forRemoval = true)
@@ -2358,6 +2369,7 @@ public interface Server extends PluginMessageRecipient, net.kyori.adventure.audi
          * @deprecated Server config options may be renamed or removed without notice. Prefer using existing API
          *  wherever possible, rather than directly reading from a server config.
          *
+         * @see #getServerConfig()
          * @return The server's paper config.
          */
         @Deprecated(since = "1.21.4", forRemoval = true)

paper-server/src/main/java/io/papermc/paper/configuration/PaperServerConfiguration.java

@@ -0,0 +1,9 @@
+package io.papermc.paper.configuration;
+
+public class PaperServerConfiguration implements ServerConfiguration {
+
+    @Override
+    public boolean isProxyOnlineMode() {
+        return GlobalConfiguration.get().proxies.isProxyOnlineMode();
+    }
+}

paper-server/src/main/java/org/bukkit/craftbukkit/CraftServer.java

@@ -12,6 +12,8 @@ import com.mojang.brigadier.StringReader;
 import com.mojang.brigadier.exceptions.CommandSyntaxException;
 import com.mojang.serialization.Dynamic;
 import com.mojang.serialization.Lifecycle;
+import io.papermc.paper.configuration.PaperServerConfiguration;
+import io.papermc.paper.configuration.ServerConfiguration;
 import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
 import java.awt.image.BufferedImage;
 import java.io.ByteArrayOutputStream;
@@ -313,6 +315,7 @@ public final class CraftServer implements Server {
     private final io.papermc.paper.logging.SysoutCatcher sysoutCatcher = new io.papermc.paper.logging.SysoutCatcher();
     private final io.papermc.paper.potion.PaperPotionBrewer potionBrewer;
     public final io.papermc.paper.SparksFly spark;
+    private final ServerConfiguration serverConfig = new PaperServerConfiguration();
 
     // Paper start - Folia region threading API
     private final io.papermc.paper.threadedregions.scheduler.FallbackRegionScheduler regionizedScheduler = new io.papermc.paper.threadedregions.scheduler.FallbackRegionScheduler();
@@ -1869,6 +1872,11 @@ public final class CraftServer implements Server {
         return this.console.usesAuthentication();
     }
 
+    @Override
+    public @NotNull ServerConfiguration getServerConfig() {
+        return serverConfig;
+    }
+
     @Override
     public boolean getAllowFlight() {
         return this.console.isFlightAllowed();