Add api methods to load and save offline users

- Add more advanced locks to protect against simultaneous loads and saves - Update stats on join on the main thread to fix errors
Archy-X · Dec 28, 2024 · e04c24a · e04c24a
1 parent a22c808
commit e04c24a
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Showing 11 changed files with 140 additions and 31 deletions.
diff --git a/api/src/main/java/dev/aurelium/auraskills/api/user/SkillsUser.java b/api/src/main/java/dev/aurelium/auraskills/api/user/SkillsUser.java
@@ -14,6 +14,7 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.TimeUnit;
 
 public interface SkillsUser {
@@ -336,4 +337,14 @@ public interface SkillsUser {
      */
     void pauseActionBar(int duration, TimeUnit timeUnit);
 
+    /**
+     * Saves the user to persistent storage asynchronously. This is only recommended if the SkillsUser represents an
+     * offline user, as changes for online users are saved automatically on logout.
+     *
+     * @param removeFromMemory Whether to remove the user from memory after saving. Will not work if the user is online.
+     * @return A future signaling when the saving is complete. The future's value is true if successful, and false if an
+     * exception was thrown.
+     */
+    CompletableFuture<Boolean> save(boolean removeFromMemory);
+
 }
diff --git a/api/src/main/java/dev/aurelium/auraskills/api/user/UserManager.java b/api/src/main/java/dev/aurelium/auraskills/api/user/UserManager.java
@@ -1,6 +1,7 @@
 package dev.aurelium.auraskills.api.user;
 
 import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
 
 public interface UserManager {
 
@@ -17,4 +18,15 @@ public interface UserManager {
      */
     SkillsUser getUser(UUID playerId);
 
+    /**
+     * Loads an offline user from storage, or gets a user from memory if the player is online. When loading offline users,
+     * the returned {@link SkillsUser} may become out of date at any point if the user logs in, since joining will always
+     * load from storage. If the UUID doesn't represent a user that exists in either memory or storage, an empty
+     * {@link SkillsUser} object will be returned where {@link SkillsUser#isLoaded()} will return false.
+     *
+     * @param playerId the UUID of the player
+     * @return a future with the SkillsUser, which is provided after the user is loaded asynchronously
+     */
+    CompletableFuture<SkillsUser> loadUser(UUID playerId);
+
 }
diff --git a/bukkit/src/main/java/dev/aurelium/auraskills/bukkit/commands/SkillsRootCommand.java b/bukkit/src/main/java/dev/aurelium/auraskills/bukkit/commands/SkillsRootCommand.java
@@ -174,7 +174,7 @@ public void onSave(CommandSender sender) {
 			Locale locale = plugin.getLocale(sender);
 			for (User user : plugin.getUserManager().getOnlineUsers()) {
 				try {
-					plugin.getStorageProvider().save(user);
+					plugin.getStorageProvider().saveSafely(user);
 				} catch (Exception e) {
 					e.printStackTrace();
 				}

diff --git a/bukkit/src/main/java/dev/aurelium/auraskills/bukkit/listeners/PlayerJoinQuit.java b/bukkit/src/main/java/dev/aurelium/auraskills/bukkit/listeners/PlayerJoinQuit.java
@@ -57,7 +57,7 @@ public void onQuit(PlayerQuitEvent event) {
 
         plugin.getScheduler().executeAsync(() -> {
             try {
-                plugin.getStorageProvider().save(user);
+                plugin.getStorageProvider().saveSafely(user);
                 plugin.getUserManager().removeUser(player.getUniqueId());
             } catch (Exception e) {
                 e.printStackTrace();

diff --git a/common/src/main/java/dev/aurelium/auraskills/common/api/implementation/ApiSkillsUser.java b/common/src/main/java/dev/aurelium/auraskills/common/api/implementation/ApiSkillsUser.java
@@ -19,6 +19,7 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.TimeUnit;
 
 public class ApiSkillsUser implements SkillsUser {
@@ -255,4 +256,22 @@ public void pauseActionBar(int duration, TimeUnit timeUnit) {
         plugin.getUiProvider().getActionBarManager().setPaused(user, duration, timeUnit);
     }
 
+    @Override
+    public CompletableFuture<Boolean> save(boolean removeFromMemory) {
+        CompletableFuture<Boolean> future = new CompletableFuture<>();
+        plugin.getScheduler().executeAsync(() -> {
+            try {
+                plugin.getStorageProvider().saveSafely(user);
+                if (removeFromMemory) {
+                    plugin.getUserManager().removeUser(user.getUuid());
+                }
+                future.complete(true);
+            } catch (Exception e) {
+                e.printStackTrace();
+                future.complete(false);
+            }
+        });
+        return future;
+    }
+
 }
diff --git a/common/src/main/java/dev/aurelium/auraskills/common/api/implementation/ApiUserManager.java b/common/src/main/java/dev/aurelium/auraskills/common/api/implementation/ApiUserManager.java
@@ -6,6 +6,7 @@
 import dev.aurelium.auraskills.common.user.User;
 
 import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
 
 public class ApiUserManager implements UserManager {
 
@@ -24,4 +25,29 @@ public SkillsUser getUser(UUID playerId) {
         return new OfflineSkillsUser(plugin, playerId);
     }
 
+    @Override
+    public CompletableFuture<SkillsUser> loadUser(UUID playerId) {
+        CompletableFuture<SkillsUser> future = new CompletableFuture<>();
+        User onlineUser = plugin.getUserManager().getUser(playerId);
+        if (onlineUser != null) {
+            future.complete(new ApiSkillsUser(onlineUser));
+        } else {
+            plugin.getScheduler().executeAsync(() -> {
+                try {
+                    plugin.getStorageProvider().load(playerId);
+                    User loadedUser = plugin.getUserManager().getUser(playerId);
+                    if (loadedUser != null) {
+                        future.complete(new ApiSkillsUser(loadedUser));
+                    } else {
+                        future.complete(new OfflineSkillsUser(plugin, playerId));
+                    }
+                } catch (Exception e) {
+                    future.complete(new OfflineSkillsUser(plugin, playerId));
+                    e.printStackTrace();
+                }
+            });
+        }
+        return future;
+    }
+
 }
diff --git a/...on/src/main/java/dev/aurelium/auraskills/common/api/implementation/OfflineSkillsUser.java b/...on/src/main/java/dev/aurelium/auraskills/common/api/implementation/OfflineSkillsUser.java
@@ -13,6 +13,7 @@
 import org.jetbrains.annotations.Nullable;
 
 import java.util.*;
+import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.TimeUnit;
 
 public class OfflineSkillsUser implements SkillsUser {
@@ -224,4 +225,11 @@ public void sendActionBar(String message, int duration, TimeUnit timeUnit) {
     public void pauseActionBar(int duration, TimeUnit timeUnit) {
 
     }
+
+    @Override
+    public CompletableFuture<Boolean> save(boolean removeFromMemory) {
+        var future = new CompletableFuture<Boolean>();
+        future.complete(false);
+        return future;
+    }
 }
diff --git a/common/src/main/java/dev/aurelium/auraskills/common/storage/StorageProvider.java b/common/src/main/java/dev/aurelium/auraskills/common/storage/StorageProvider.java
@@ -12,32 +12,53 @@
 
 import java.util.List;
 import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
 
 public abstract class StorageProvider {
 
+    private static final long SAVE_TIMEOUT_MS = 2000;
+    private static final long LOAD_TIMEOUT_MS = 2000;
+
     public final AuraSkillsPlugin plugin;
     public final UserManager userManager;
+    private final ConcurrentHashMap<UUID, ReentrantReadWriteLock> userLocks = new ConcurrentHashMap<>();
 
     public StorageProvider(AuraSkillsPlugin plugin) {
         this.userManager = plugin.getUserManager();
         this.plugin = plugin;
     }
 
     public void load(UUID uuid) throws Exception {
-        User user = loadRaw(uuid);
-        fixInvalidData(user);
+        ReentrantReadWriteLock lock = getUserLock(uuid);
+        boolean lockAcquired = false;
+        try {
+            lockAcquired = lock.readLock().tryLock(LOAD_TIMEOUT_MS, TimeUnit.MILLISECONDS);
+            if (!lockAcquired) {
+                plugin.logger().warn("Load timout exceeded for user " + uuid);
+            }
 
-        plugin.getUserManager().addUser(user);
+            User user = loadRaw(uuid);
+            fixInvalidData(user);
 
-        // Update stats
-        plugin.getStatManager().updateStats(user);
+            plugin.getUserManager().addUser(user);
 
-        // Call event
-        plugin.getScheduler().executeSync(() -> plugin.getEventHandler().callUserLoadEvent(user));
+            plugin.getScheduler().executeSync(() -> {
+                plugin.getStatManager().updateStats(user); // Update stats
+                plugin.getEventHandler().callUserLoadEvent(user); // Call event
+            });
 
-        // Update permissions
-        plugin.getRewardManager().updatePermissions(user);
+            // Update permissions
+            plugin.getRewardManager().updatePermissions(user);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        } finally {
+            if (lockAcquired) {
+                lock.readLock().unlock();
+            }
+            removeUserLock(uuid, lock);
+        }
     }
 
     protected abstract User loadRaw(UUID uuid) throws Exception;
@@ -59,6 +80,26 @@ public void load(UUID uuid) throws Exception {
      */
     public abstract void applyState(UserState state) throws Exception;
 
+    public void saveSafely(@NotNull User user) {
+        ReentrantReadWriteLock lock = getUserLock(user.getUuid());
+        boolean lockAcquired = false;
+        try {
+            lockAcquired = lock.writeLock().tryLock(SAVE_TIMEOUT_MS, TimeUnit.MILLISECONDS);
+            if (!lockAcquired) {
+                plugin.logger().warn("Save timeout exceeded for user " + user.getUuid());
+                return;
+            }
+            save(user);
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            if (lockAcquired) {
+                lock.writeLock().unlock();
+            }
+            removeUserLock(user.getUuid(), lock);
+        }
+    }
+
     public abstract void save(@NotNull User user) throws Exception;
 
     public abstract void delete(UUID uuid) throws Exception;
@@ -77,12 +118,8 @@ public void startAutoSaving() {
             public void run() {
                 for (User user : userManager.getOnlineUsers()) {
                     try {
-                        if (user.isSaving()) {
-                            continue;
-                        }
-                        save(user);
+                        saveSafely(user);
                     } catch (Exception e) {
-                        user.setSaving(false);
                         plugin.logger().warn("Error running auto-save on user data:");
                         e.printStackTrace();
                     }
@@ -111,4 +148,14 @@ private void fixInvalidData(User user) {
         }
     }
 
+    protected ReentrantReadWriteLock getUserLock(UUID uuid) {
+        return userLocks.computeIfAbsent(uuid, id -> new ReentrantReadWriteLock());
+    }
+
+    protected void removeUserLock(UUID uuid, ReentrantReadWriteLock lock) {
+        if (lock.getReadLockCount() == 0 && !lock.isWriteLocked()) {
+            userLocks.remove(uuid);
+        }
+    }
+
 }
diff --git a/common/src/main/java/dev/aurelium/auraskills/common/storage/backup/BackupProvider.java b/common/src/main/java/dev/aurelium/auraskills/common/storage/backup/BackupProvider.java
@@ -44,7 +44,7 @@ public File saveBackup(boolean savePlayerData) throws Exception {
         // Save online players
         if (savePlayerData) {
             for (User user : plugin.getUserManager().getOnlineUsers()) {
-                plugin.getStorageProvider().save(user);
+                plugin.getStorageProvider().saveSafely(user);
             }
         }
 

diff --git a/common/src/main/java/dev/aurelium/auraskills/common/storage/file/FileStorageProvider.java b/common/src/main/java/dev/aurelium/auraskills/common/storage/file/FileStorageProvider.java
@@ -285,9 +285,6 @@ public void applyState(UserState state) throws Exception {
 
     @Override
     public void save(@NotNull User user) throws Exception {
-        if (user.isSaving()) return;
-        user.setSaving(true);
-
         CommentedConfigurationNode root = loadYamlFile(user.getUuid());
 
         root.node("uuid").set(user.getUuid().toString());
@@ -386,7 +383,6 @@ public void save(@NotNull User user) throws Exception {
         }
 
         saveYamlFile(root, user.getUuid());
-        user.setSaving(false);
     }
 
     private void saveYamlFile(CommentedConfigurationNode root, UUID uuid) throws ConfigurateException {

diff --git a/common/src/main/java/dev/aurelium/auraskills/common/user/User.java b/common/src/main/java/dev/aurelium/auraskills/common/user/User.java
@@ -54,7 +54,6 @@ public abstract class User {
     private long lastJobSelectTime;
     private final List<AntiAfkLog> sessionAntiAfkLogs;
 
-    private boolean saving;
     private boolean shouldSave;
     private boolean blank = true;
 
@@ -78,7 +77,6 @@ public User(UUID uuid, AuraSkillsPlugin plugin) {
         this.metadata = new ConcurrentHashMap<>();
         this.actionBarSettings = new ConcurrentHashMap<>();
         this.unclaimedItems = new LinkedList<>();
-        this.saving = false;
         this.shouldSave = true;
         this.mana = Traits.MAX_MANA.isEnabled() ? Traits.MAX_MANA.optionDouble("base") : 0.0;
         this.multipliers = new HashMap<>();
@@ -464,14 +462,6 @@ public int getJobLimit() {
 
     public abstract boolean canSelectJob(@NotNull Skill skill);
 
-    public boolean isSaving() {
-        return saving;
-    }
-
-    public void setSaving(boolean saving) {
-        this.saving = saving;
-    }
-
     public boolean shouldNotSave() {
         return !shouldSave;
     }