refactor: add serialization identifier dependencies for applying data (#309)

* refactor: add serialization identifier dependencies for applying data

* fix: correct issues with deterministic sync order

* refactor: adjust base data type dependencies

* refactor: cleanup imports/trim whitespace

* docs: Document Identifier dependencies

* feat: fix issues with health scaling

common/src/main/java/net/william278/husksync/HuskSync.java

@@ -31,7 +31,7 @@ import net.william278.husksync.adapter.DataAdapter;
 import net.william278.husksync.config.ConfigProvider;
 import net.william278.husksync.data.Data;
 import net.william278.husksync.data.Identifier;
-import net.william278.husksync.data.Serializer;
+import net.william278.husksync.data.SerializerRegistry;
 import net.william278.husksync.database.Database;
 import net.william278.husksync.event.EventDispatcher;
 import net.william278.husksync.migrator.Migrator;
@@ -52,7 +52,7 @@ import java.util.logging.Level;
 /**
  * Abstract implementation of the HuskSync plugin.
  */
-public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider {
+public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider, SerializerRegistry {
 
     int SPIGOT_RESOURCE_ID = 97144;
 
@@ -98,43 +98,6 @@ public interface HuskSync extends Task.Supplier, EventDispatcher, ConfigProvider
     @NotNull
     DataAdapter getDataAdapter();
 
-    /**
-     * Returns the data serializer for the given {@link Identifier}
-     */
-    @NotNull
-    <T extends Data> Map<Identifier, Serializer<T>> getSerializers();
-
-    /**
-     * Register a data serializer for the given {@link Identifier}
-     *
-     * @param identifier the {@link Identifier}
-     * @param serializer the {@link Serializer}
-     */
-    default void registerSerializer(@NotNull Identifier identifier,
-                                    @NotNull Serializer<? extends Data> serializer) {
-        if (identifier.isCustom()) {
-            log(Level.INFO, String.format("Registered custom data type: %s", identifier));
-        }
-        getSerializers().put(identifier, (Serializer<Data>) serializer);
-    }
-
-    /**
-     * Get the {@link Identifier} for the given key
-     */
-    default Optional<Identifier> getIdentifier(@NotNull String key) {
-        return getSerializers().keySet().stream().filter(identifier -> identifier.toString().equals(key)).findFirst();
-    }
-
-    /**
-     * Get the set of registered data types
-     *
-     * @return the set of registered data types
-     */
-    @NotNull
-    default Set<Identifier> getRegisteredDataTypes() {
-        return getSerializers().keySet();
-    }
-
     /**
      * Returns the data syncer implementation
      *

common/src/main/java/net/william278/husksync/adapter/GsonAdapter.java

@@ -49,7 +49,7 @@ public class GsonAdapter implements DataAdapter {
 
     @Override
     @NotNull
-    public <A extends Adaptable> A fromBytes(@NotNull byte[] data, @NotNull Class<A> type) throws AdaptionException {
+    public <A extends Adaptable> A fromBytes(byte[] data, @NotNull Class<A> type) throws AdaptionException {
         return this.fromJson(new String(data, StandardCharsets.UTF_8), type);
     }
 

common/src/main/java/net/william278/husksync/adapter/SnappyGsonAdapter.java

@@ -31,7 +31,6 @@ public class SnappyGsonAdapter extends GsonAdapter {
         super(plugin);
     }
 
-    @NotNull
     @Override
     public <A extends Adaptable> byte[] toBytes(@NotNull A data) throws AdaptionException {
         try {
@@ -43,7 +42,7 @@ public class SnappyGsonAdapter extends GsonAdapter {
 
     @NotNull
     @Override
-    public <A extends Adaptable> A fromBytes(@NotNull byte[] data, @NotNull Class<A> type) throws AdaptionException {
+    public <A extends Adaptable> A fromBytes(byte[] data, @NotNull Class<A> type) throws AdaptionException {
         try {
             return super.fromBytes(decompressBytes(data), type);
         } catch (IOException e) {

common/src/main/java/net/william278/husksync/api/HuskSyncAPI.java

@@ -378,6 +378,17 @@ public class HuskSyncAPI {
         plugin.registerSerializer(identifier, serializer);
     }
 
+    /**
+     * Get a registered data serializer by its identifier
+     *
+     * @param identifier The identifier of the data type to get the serializer for
+     * @return The serializer for the given identifier, or an empty optional if the serializer isn't registered
+     * @since 3.5.4
+     */
+    public Optional<Serializer<Data>> getDataSerializer(@NotNull Identifier identifier) {
+        return plugin.getSerializer(identifier);
+    }
+
     /**
      * Get a {@link DataSnapshot.Unpacked} from a {@link DataSnapshot.Packed}
      *

common/src/main/java/net/william278/husksync/command/HuskSyncCommand.java

@@ -241,10 +241,19 @@ public class HuskSyncCommand extends Command implements TabProvider {
                 JoinConfiguration.commas(true),
                 plugin.getRegisteredDataTypes().stream().map(i -> {
                     boolean enabled = plugin.getSettings().getSynchronization().isFeatureEnabled(i);
-                    return Component.textOfChildren(Component
-                                    .text(i.toString()).appendSpace().append(Component.text(enabled ? '✔' : '❌')))
+                    return Component.textOfChildren(Component.text(i.toString())
+                                    .appendSpace().append(Component.text(enabled ? '✔' : '❌')))
                             .color(enabled ? NamedTextColor.GREEN : NamedTextColor.RED)
-                            .hoverEvent(HoverEvent.showText(Component.text(enabled ? "Enabled" : "Disabled")));
+                            .hoverEvent(HoverEvent.showText(
+                                    Component.text(enabled ? "Enabled" : "Disabled")
+                                            .append(Component.newline())
+                                            .append(Component.text("Dependencies: %s".formatted(i.getDependencies()
+                                                    .isEmpty() ? "(None)" : i.getDependencies().stream()
+                                                    .map(d -> "%s (%s)".formatted(
+                                                            d.getKey().value(), d.isRequired() ? "Required" : "Optional"
+                                                    )).collect(Collectors.joining(", ")))
+                                            ).color(NamedTextColor.GRAY))
+                            ));
                 }).toList()
         ));
 

common/src/main/java/net/william278/husksync/data/DataSnapshot.java

@@ -370,7 +370,7 @@ public class DataSnapshot {
     public static class Unpacked extends DataSnapshot implements DataHolder {
 
         @Expose(serialize = false, deserialize = false)
-        private final Map<Identifier, Data> deserialized;
+        private final TreeMap<Identifier, Data> deserialized;
 
         private Unpacked(@NotNull UUID id, boolean pinned, @NotNull OffsetDateTime timestamp,
                          @NotNull String saveCause, @NotNull String serverName, @NotNull Map<String, String> data,
@@ -381,7 +381,7 @@ public class DataSnapshot {
         }
 
         private Unpacked(@NotNull UUID id, boolean pinned, @NotNull OffsetDateTime timestamp,
-                         @NotNull String saveCause, @NotNull String serverName, @NotNull Map<Identifier, Data> data,
+                         @NotNull String saveCause, @NotNull String serverName, @NotNull TreeMap<Identifier, Data> data,
                          @NotNull Version minecraftVersion, @NotNull String platformType, int formatVersion) {
             super(id, pinned, timestamp, saveCause, serverName, Map.of(), minecraftVersion, platformType, formatVersion);
             this.deserialized = data;
@@ -389,25 +389,25 @@ public class DataSnapshot {
 
         @NotNull
         @ApiStatus.Internal
-        private Map<Identifier, Data> deserializeData(@NotNull HuskSync plugin) {
+        private TreeMap<Identifier, Data> deserializeData(@NotNull HuskSync plugin) {
             return data.entrySet().stream()
-                    .map((entry) -> plugin.getIdentifier(entry.getKey()).map(id -> Map.entry(
-                            id, plugin.getSerializers().get(id).deserialize(entry.getValue(), getMinecraftVersion())
-                    )).orElse(null))
-                    .filter(Objects::nonNull)
-                    .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+                    .filter(e -> plugin.getIdentifier(e.getKey()).isPresent())
+                    .map(entry -> Map.entry(plugin.getIdentifier(entry.getKey()).orElseThrow(), entry.getValue()))
+                    .collect(Collectors.toMap(
+                            Map.Entry::getKey,
+                            entry -> plugin.deserializeData(entry.getKey(), entry.getValue()),
+                            (a, b) -> b, () -> Maps.newTreeMap(SerializerRegistry.DEPENDENCY_ORDER_COMPARATOR)
+                    ));
         }
 
         @NotNull
         @ApiStatus.Internal
         private Map<String, String> serializeData(@NotNull HuskSync plugin) {
             return deserialized.entrySet().stream()
-                    .map((entry) -> Map.entry(entry.getKey().toString(),
-                            Objects.requireNonNull(
-                                    plugin.getSerializers().get(entry.getKey()),
-                                    String.format("No serializer found for %s", entry.getKey())
-                            ).serialize(entry.getValue())))
-                    .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue));
+                    .collect(Collectors.toMap(
+                            entry -> entry.getKey().toString(),
+                            entry -> plugin.serializeData(entry.getKey(), entry.getValue())
+                    ));
         }
 
         /**
@@ -453,12 +453,12 @@ public class DataSnapshot {
         private String serverName;
         private boolean pinned;
         private OffsetDateTime timestamp;
-        private final Map<Identifier, Data> data;
+        private final TreeMap<Identifier, Data> data;
 
         private Builder(@NotNull HuskSync plugin) {
             this.plugin = plugin;
             this.pinned = false;
-            this.data = Maps.newHashMap();
+            this.data = Maps.newTreeMap(SerializerRegistry.DEPENDENCY_ORDER_COMPARATOR);
             this.timestamp = OffsetDateTime.now();
             this.id = UUID.randomUUID();
             this.serverName = plugin.getServerName();

common/src/main/java/net/william278/husksync/data/Identifier.java

@@ -19,40 +19,81 @@
 
 package net.william278.husksync.data;
 
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
 import net.kyori.adventure.key.InvalidKeyException;
 import net.kyori.adventure.key.Key;
 import org.intellij.lang.annotations.Subst;
 import org.jetbrains.annotations.ApiStatus;
 import org.jetbrains.annotations.NotNull;
 
+import java.util.Collections;
+import java.util.Comparator;
 import java.util.Map;
+import java.util.Set;
 import java.util.stream.Stream;
 
 /**
  * Identifiers of different types of {@link Data}s
  */
+@Getter
 public class Identifier {
 
-    public static Identifier INVENTORY = huskSync("inventory", true);
-    public static Identifier ENDER_CHEST = huskSync("ender_chest", true);
-    public static Identifier POTION_EFFECTS = huskSync("potion_effects", true);
-    public static Identifier ADVANCEMENTS = huskSync("advancements", true);
-    public static Identifier LOCATION = huskSync("location", false);
-    public static Identifier STATISTICS = huskSync("statistics", true);
-    public static Identifier HEALTH = huskSync("health", true);
-    public static Identifier HUNGER = huskSync("hunger", true);
-    public static Identifier ATTRIBUTES = huskSync("attributes", true);
-    public static Identifier EXPERIENCE = huskSync("experience", true);
-    public static Identifier GAME_MODE = huskSync("game_mode", true);
-    public static Identifier FLIGHT_STATUS = huskSync("flight_status", true);
-    public static Identifier PERSISTENT_DATA = huskSync("persistent_data", true);
+    // Built-in identifiers
+    public static final Identifier PERSISTENT_DATA = huskSync("persistent_data", true);
+    public static final Identifier INVENTORY = huskSync("inventory", true);
+    public static final Identifier ENDER_CHEST = huskSync("ender_chest", true);
+    public static final Identifier ADVANCEMENTS = huskSync("advancements", true);
+    public static final Identifier STATISTICS = huskSync("statistics", true);
+    public static final Identifier POTION_EFFECTS = huskSync("potion_effects", true);
+    public static final Identifier GAME_MODE = huskSync("game_mode", false);
+    public static final Identifier FLIGHT_STATUS = huskSync("flight_status", true,
+            Dependency.optional("game_mode")
+    );
+    public static final Identifier ATTRIBUTES = huskSync("attributes", true,
+            Dependency.required("potion_effects")
+    );
+    public static final Identifier HEALTH = huskSync("health", true,
+            Dependency.optional("attributes")
+    );
+    public static final Identifier HUNGER = huskSync("hunger", true,
+            Dependency.optional("attributes")
+    );
+    public static final Identifier EXPERIENCE = huskSync("experience", true,
+            Dependency.optional("advancements")
+    );
+    public static final Identifier LOCATION = huskSync("location", false,
+            Dependency.optional("flight_status"),
+            Dependency.optional("potion_effects")
+    );
 
     private final Key key;
-    private final boolean configDefault;
+    private final boolean enabledByDefault;
+    @Getter
+    private final Set<Dependency> dependencies;
 
-    private Identifier(@NotNull Key key, boolean configDefault) {
+    private Identifier(@NotNull Key key, boolean enabledByDefault, @NotNull Set<Dependency> dependencies) {
         this.key = key;
-        this.configDefault = configDefault;
+        this.enabledByDefault = enabledByDefault;
+        this.dependencies = dependencies;
+    }
+
+    /**
+     * Create an identifier from a {@link Key}
+     *
+     * @param key          the key
+     * @param dependencies the dependencies
+     * @return the identifier
+     * @since 3.5.4
+     */
+    @NotNull
+    public static Identifier from(@NotNull Key key, @NotNull Set<Dependency> dependencies) {
+        if (key.namespace().equals("husksync")) {
+            throw new IllegalArgumentException("You cannot register a key with \"husksync\" as the namespace!");
+        }
+        return new Identifier(key, true, dependencies);
     }
 
     /**
@@ -64,10 +105,7 @@ public class Identifier {
      */
     @NotNull
     public static Identifier from(@NotNull Key key) {
-        if (key.namespace().equals("husksync")) {
-            throw new IllegalArgumentException("You cannot register a key with \"husksync\" as the namespace!");
-        }
-        return new Identifier(key, true);
+        return from(key, Collections.emptySet());
     }
 
     /**
@@ -83,25 +121,34 @@ public class Identifier {
         return from(Key.key(plugin, name));
     }
 
+    /**
+     * Create an identifier from a namespace, value, and dependencies
+     *
+     * @param plugin       the namespace
+     * @param name         the value
+     * @param dependencies the dependencies
+     * @return the identifier
+     * @since 3.5.4
+     */
+    @NotNull
+    public static Identifier from(@Subst("plugin") @NotNull String plugin, @Subst("null") @NotNull String name,
+                                  @NotNull Set<Dependency> dependencies) {
+        return from(Key.key(plugin, name), dependencies);
+    }
+
+    // Return an identifier with a HuskSync namespace
     @NotNull
     private static Identifier huskSync(@Subst("null") @NotNull String name,
                                        boolean configDefault) throws InvalidKeyException {
-        return new Identifier(Key.key("husksync", name), configDefault);
+        return new Identifier(Key.key("husksync", name), configDefault, Collections.emptySet());
     }
 
+    // Return an identifier with a HuskSync namespace
     @NotNull
-    @SuppressWarnings("unused")
-    private static Identifier parse(@NotNull String key) throws InvalidKeyException {
-        return huskSync(key, true);
-    }
-
-    public boolean isEnabledByDefault() {
-        return configDefault;
-    }
-
-    @NotNull
-    private Map.Entry<String, Boolean> getConfigEntry() {
-        return Map.entry(getKeyValue(), configDefault);
+    private static Identifier huskSync(@Subst("null") @NotNull String name,
+                                       @SuppressWarnings("SameParameterValue") boolean configDefault,
+                                       @NotNull Dependency... dependents) throws InvalidKeyException {
+        return new Identifier(Key.key("husksync", name), configDefault, Set.of(dependents));
     }
 
     /**
@@ -122,6 +169,17 @@ public class Identifier {
                 .toArray(Map.Entry[]::new));
     }
 
+    /**
+     * Returns {@code true} if the identifier depends on the given identifier
+     *
+     * @param identifier the identifier to check
+     * @return {@code true} if the identifier depends on the given identifier
+     * @since 3.5.4
+     */
+    public boolean dependsOn(@NotNull Identifier identifier) {
+        return dependencies.contains(Dependency.required(identifier.key));
+    }
+
     /**
      * Get the namespace of the identifier
      *
@@ -176,4 +234,85 @@ public class Identifier {
         return false;
     }
 
+    // Get the config entry for the identifier
+    @NotNull
+    private Map.Entry<String, Boolean> getConfigEntry() {
+        return Map.entry(getKeyValue(), enabledByDefault);
+    }
+
+    /**
+     * Compares two identifiers based on their dependencies.
+     * <p>
+     * If this identifier contains a dependency on the other, it should come after & vice versa
+     *
+     * @since 3.5.4
+     */
+    @NoArgsConstructor(access = AccessLevel.PACKAGE)
+    static class DependencyOrderComparator implements Comparator<Identifier> {
+
+        @Override
+        public int compare(@NotNull Identifier i1, @NotNull Identifier i2) {
+            if (i1.equals(i2)) {
+                return 0;
+            }
+            if (i1.dependsOn(i2)) {
+                if (i2.dependsOn(i1)) {
+                    throw new IllegalArgumentException(
+                            "Found circular dependency between %s and %s".formatted(i1.getKey(), i2.getKey())
+                    );
+                }
+                return 1;
+            }
+            return -1;
+        }
+
+    }
+
+    /**
+     * Represents a data dependency of an identifier
+     *
+     * @since 3.5.4
+     */
+    @Getter
+    @AllArgsConstructor(access = AccessLevel.PRIVATE)
+    public static class Dependency {
+        /**
+         * Key of the data dependency see {@code Identifier#key()}
+         */
+        private Key key;
+        /**
+         * Whether the data dependency is required to be present & enabled for the dependant data to enabled
+         */
+        private boolean required;
+
+        @NotNull
+        protected static Dependency required(@NotNull Key identifier) {
+            return new Dependency(identifier, true);
+        }
+
+        @NotNull
+        public static Dependency optional(@NotNull Key identifier) {
+            return new Dependency(identifier, false);
+        }
+
+        @NotNull
+        @SuppressWarnings("SameParameterValue")
+        private static Dependency required(@Subst("null") @NotNull String identifier) {
+            return required(Key.key("husksync", identifier));
+        }
+
+        @NotNull
+        private static Dependency optional(@Subst("null") @NotNull String identifier) {
+            return optional(Key.key("husksync", identifier));
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (obj instanceof Dependency other) {
+                return key.equals(other.key);
+            }
+            return false;
+        }
+    }
+
 }

common/src/main/java/net/william278/husksync/data/SerializerRegistry.java

@@ -0,0 +1,162 @@
+/*
+ * This file is part of HuskSync, licensed under the Apache License 2.0.
+ *
+ *  Copyright (c) William278 <will27528@gmail.com>
+ *  Copyright (c) contributors
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package net.william278.husksync.data;
+
+import net.william278.husksync.HuskSync;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.*;
+import java.util.logging.Level;
+
+public interface SerializerRegistry {
+
+    // Comparator for ordering identifiers based on dependency
+    @NotNull
+    @ApiStatus.Internal
+    Comparator<Identifier> DEPENDENCY_ORDER_COMPARATOR = new Identifier.DependencyOrderComparator();
+
+    /**
+     * Returns the data serializer for the given {@link Identifier}
+     *
+     * @since 3.0
+     */
+    @NotNull
+    <T extends Data> TreeMap<Identifier, Serializer<T>> getSerializers();
+
+    /**
+     * Register a data serializer for the given {@link Identifier}
+     *
+     * @param identifier the {@link Identifier}
+     * @param serializer the {@link Serializer}
+     * @since 3.0
+     */
+    @SuppressWarnings("unchecked")
+    default void registerSerializer(@NotNull Identifier identifier,
+                                    @NotNull Serializer<? extends Data> serializer) {
+        if (identifier.isCustom()) {
+            getPlugin().log(Level.INFO, "Registered custom data type: %s".formatted(identifier));
+        }
+        getSerializers().put(identifier, (Serializer<Data>) serializer);
+    }
+
+    /**
+     * Ensure dependencies for identifiers that have required dependencies are met
+     * <p>
+     * This checks the dependencies of all registered identifiers and throws an {@link IllegalStateException}
+     * if a dependency has not been registered or enabled via the config
+     *
+     * @since 3.5.4
+     */
+    default void validateDependencies() throws IllegalStateException {
+        getSerializers().keySet().stream().filter(this::isDataTypeEnabled)
+                .forEach(identifier -> {
+                    final List<String> unmet = identifier.getDependencies().stream()
+                            .filter(Identifier.Dependency::isRequired)
+                            .filter(dep -> !isDataTypeAvailable(dep.getKey().asString()))
+                            .map(dep -> dep.getKey().asString()).toList();
+                    if (!unmet.isEmpty()) {
+                        throw new IllegalStateException(
+                                "\"%s\" data requires the following disabled data types to facilitate syncing: %s"
+                                .formatted(identifier, String.join(", ", unmet))
+                        );
+                    }
+                });
+    }
+
+    /**
+     * Get the {@link Identifier} for the given key
+     *
+     * @since 3.0
+     */
+    default Optional<Identifier> getIdentifier(@NotNull String key) {
+        return getSerializers().keySet().stream()
+                .filter(id -> id.getKey().asString().equals(key)).findFirst();
+    }
+
+    /**
+     * Get a data serializer for the given {@link Identifier}
+     *
+     * @param identifier the {@link Identifier} to get the serializer for
+     * @return the {@link Serializer} for the given {@link Identifier}
+     * @since 3.5.4
+     */
+    default Optional<Serializer<Data>> getSerializer(@NotNull Identifier identifier) {
+        return getSerializers().entrySet().stream()
+                .filter(entry -> entry.getKey().getKey().equals(identifier.getKey()))
+                .map(Map.Entry::getValue).findFirst();
+    }
+
+    /**
+     * Serialize data for the given {@link Identifier}
+     *
+     * @param identifier the {@link Identifier} to serialize data for
+     * @param data       the data to serialize
+     * @return the serialized data
+     * @throws IllegalArgumentException if no serializer is found for the given {@link Identifier}
+     * @since 3.5.4
+     */
+    @NotNull
+    default String serializeData(@NotNull Identifier identifier, @NotNull Data data) throws IllegalStateException {
+        return getSerializer(identifier).map(serializer -> serializer.serialize(data))
+                .orElseThrow(() -> new IllegalStateException("No serializer found for %s".formatted(identifier)));
+    }
+
+    /**
+     * Deserialize data for the given {@link Identifier}
+     *
+     * @param identifier the {@link Identifier} to deserialize data for
+     * @param data       the data to deserialize
+     * @return the deserialized data
+     * @throws IllegalStateException if no serializer is found for the given {@link Identifier}
+     * @since 3.5.4
+     */
+    @NotNull
+    default Data deserializeData(@NotNull Identifier identifier, @NotNull String data) throws IllegalStateException {
+        return getSerializer(identifier).map(serializer -> serializer.deserialize(data)).orElseThrow(
+                () -> new IllegalStateException("No serializer found for %s".formatted(identifier))
+        );
+    }
+
+    /**
+     * Get the set of registered data types
+     *
+     * @return the set of registered data types
+     * @since 3.0
+     */
+    @NotNull
+    default Set<Identifier> getRegisteredDataTypes() {
+        return getSerializers().keySet();
+    }
+
+    // Returns if a data type is available and enabled in the config
+    private boolean isDataTypeAvailable(@NotNull String key) {
+        return getIdentifier(key).map(this::isDataTypeEnabled).orElse(false);
+    }
+
+    // Returns if a data type is enabled in the config
+    private boolean isDataTypeEnabled(@NotNull Identifier identifier) {
+        return getPlugin().getSettings().getSynchronization().isFeatureEnabled(identifier);
+    }
+
+    @NotNull
+    HuskSync getPlugin();
+
+}

common/src/main/java/net/william278/husksync/data/UserDataHolder.java

@@ -34,7 +34,7 @@ import java.util.logging.Level;
 public interface UserDataHolder extends DataHolder {
 
     /**
-     * Get the data that is enabled for syncing in the config
+     * Get the data enabled for syncing in the config
      *
      * @return the data that is enabled for syncing
      * @since 3.0