Use Paper player profiles if available.

Also fall back to caching to memory if SQLite can't be linked.
This is a common issue with (bad) server hosts who mount /tmp as noexec,
which causes sqlite's native binaries to fail to link.

config/checkstyle/import-control.xml

@@ -16,9 +16,14 @@
     <allow pkg="org.khelekore"/>
     <allow pkg="org.flywaydb"/>
     <allow pkg="org.yaml"/>
-    <allow pkg="org.json"/>
     <allow pkg="org.enginehub.piston"/>
 
+    <subpackage name="util.profile.resolver">
+      <allow pkg="org.bukkit"/>
+      <allow pkg="io.papermc.lib"/>
+      <allow pkg="com.destroystokyo.paper"/>
+    </subpackage>
+
     <subpackage name="bukkit">
       <allow pkg="org.bukkit"/>
       <allow pkg="org.bstats.bukkit"/>
@@ -26,16 +31,6 @@
       <allow pkg="com.destroystokyo.paper"/>
     </subpackage>
 
-    <subpackage name="sponge">
-      <allow pkg="org.spongepowered"/>
-      <allow pkg="org.bstats.sponge"/>
-      <allow pkg="com.flowpowered"/>
-    </subpackage>
-
-    <subpackage name="forge">
-      <allow pkg="net.minecraft"/>
-      <allow pkg="net.minecraftforge"/>
-    </subpackage>
   </subpackage>
 
 </import-control>

worldguard-bukkit/src/main/java/com/sk89q/worldguard/bukkit/BukkitWorldGuardPlatform.java

@@ -25,6 +25,7 @@ import com.sk89q.worldedit.world.gamemode.GameMode;
 import com.sk89q.worldedit.world.gamemode.GameModes;
 import com.sk89q.worldguard.LocalPlayer;
 import com.sk89q.worldguard.WorldGuard;
+import com.sk89q.worldguard.util.profile.resolver.PaperProfileService;
 import com.sk89q.worldguard.bukkit.protection.events.flags.FlagContextCreateEvent;
 import com.sk89q.worldguard.bukkit.session.BukkitSessionManager;
 import com.sk89q.worldguard.bukkit.util.report.PerformanceReport;
@@ -39,12 +40,20 @@ import com.sk89q.worldguard.internal.platform.WorldGuardPlatform;
 import com.sk89q.worldguard.protection.flags.FlagContext;
 import com.sk89q.worldguard.protection.regions.RegionContainer;
 import com.sk89q.worldguard.session.SessionManager;
+import com.sk89q.worldguard.util.profile.cache.ProfileCache;
+import com.sk89q.worldguard.util.profile.resolver.BukkitPlayerService;
+import com.sk89q.worldguard.util.profile.resolver.CacheForwardingService;
+import com.sk89q.worldguard.util.profile.resolver.CombinedProfileService;
+import com.sk89q.worldguard.util.profile.resolver.HttpRepositoryService;
+import com.sk89q.worldguard.util.profile.resolver.ProfileService;
+import io.papermc.lib.PaperLib;
 import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.permissions.Permissible;
 
 import java.nio.file.Path;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 import java.util.stream.Collectors;
@@ -228,4 +237,18 @@ public class BukkitWorldGuardPlatform implements WorldGuardPlatform {
         report.add(new WorldReport());
         report.add(new PerformanceReport());
     }
+
+    @Override
+    public ProfileService createProfileService(ProfileCache profileCache) {
+        List<ProfileService> services = new ArrayList<>();
+        if (PaperLib.isPaper()) {
+            // Paper has a shared cache, and will do lookups for us if needed
+            services.add(PaperProfileService.getInstance());
+        } else {
+            services.add(BukkitPlayerService.getInstance());
+            services.add(HttpRepositoryService.forMinecraft());
+        }
+        return new CacheForwardingService(new CombinedProfileService(services),
+                profileCache);
+    }
 }

worldguard-bukkit/src/main/java/com/sk89q/worldguard/util/profile/resolver/PaperProfileService.java

@@ -0,0 +1,57 @@
+/*
+ * WorldGuard, a suite of tools for Minecraft
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldGuard team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldguard.util.profile.resolver;
+
+import com.destroystokyo.paper.profile.PlayerProfile;
+import com.sk89q.worldguard.util.profile.Profile;
+import io.papermc.lib.PaperLib;
+import org.bukkit.Bukkit;
+
+import javax.annotation.Nullable;
+
+public final class PaperProfileService extends SingleRequestService {
+    private static final PaperProfileService INSTANCE = new PaperProfileService();
+
+    private PaperProfileService() {
+        if (!PaperLib.isPaper()) {
+            throw new IllegalStateException("Attempt to access PaperProfileService on non-Paper server.");
+        }
+    }
+
+    @Override
+    public int getIdealRequestLimit() {
+        return Integer.MAX_VALUE;
+    }
+
+    @Override
+    @Nullable
+    public Profile findByName(String name) {
+        PlayerProfile profile = Bukkit.createProfile(name);
+        if (profile.complete(false)) {
+            //noinspection ConstantConditions - completeFromCache guarantees non-null on success
+            return new Profile(profile.getId(), profile.getName());
+        }
+        return null;
+    }
+
+    public static PaperProfileService getInstance() {
+        return INSTANCE;
+    }
+}

worldguard-core/src/main/java/com/sk89q/worldguard/WorldGuard.java

@@ -27,10 +27,6 @@ import com.sk89q.minecraft.util.commands.CommandException;
 import com.sk89q.worldguard.util.profile.cache.HashMapCache;
 import com.sk89q.worldguard.util.profile.cache.ProfileCache;
 import com.sk89q.worldguard.util.profile.cache.SQLiteCache;
-import com.sk89q.worldguard.util.profile.resolver.BukkitPlayerService;
-import com.sk89q.worldguard.util.profile.resolver.CacheForwardingService;
-import com.sk89q.worldguard.util.profile.resolver.CombinedProfileService;
-import com.sk89q.worldguard.util.profile.resolver.HttpRepositoryService;
 import com.sk89q.worldguard.util.profile.resolver.ProfileService;
 import com.sk89q.worldedit.extension.platform.Actor;
 import com.sk89q.worldedit.util.task.SimpleSupervisor;
@@ -85,16 +81,12 @@ public final class WorldGuard {
 
         try {
             profileCache = new SQLiteCache(new File(cacheDir, "profiles.sqlite"));
-        } catch (IOException e) {
-            logger.log(Level.WARNING, "Failed to initialize SQLite profile cache");
+        } catch (IOException | UnsatisfiedLinkError ignored) {
+            logger.log(Level.WARNING, "Failed to initialize SQLite profile cache. Cache is memory-only.");
             profileCache = new HashMapCache();
         }
 
-        profileService = new CacheForwardingService(
-                new CombinedProfileService(
-                        BukkitPlayerService.getInstance(),
-                        HttpRepositoryService.forMinecraft()),
-                profileCache);
+        profileService = getPlatform().createProfileService(profileCache);
 
         getPlatform().load();
     }

worldguard-core/src/main/java/com/sk89q/worldguard/internal/platform/WorldGuardPlatform.java

@@ -27,6 +27,8 @@ import com.sk89q.worldguard.config.ConfigurationManager;
 import com.sk89q.worldguard.protection.flags.FlagContext;
 import com.sk89q.worldguard.protection.regions.RegionContainer;
 import com.sk89q.worldguard.session.SessionManager;
+import com.sk89q.worldguard.util.profile.cache.ProfileCache;
+import com.sk89q.worldguard.util.profile.resolver.ProfileService;
 
 import java.nio.file.Path;
 
@@ -148,4 +150,9 @@ public interface WorldGuardPlatform {
      * @param report The reportlist
      */
     void addPlatformReports(ReportList report);
+
+    /**
+     * Internal use.
+     */
+    ProfileService createProfileService(ProfileCache profileCache);
 }