Implement Fabric Permission API

fabric-item-api-v1/src/main/java/net/fabricmc/fabric/api/item/v1/DefaultItemComponentEvents.java

@@ -23,6 +23,7 @@
 
 import net.minecraft.core.HolderLookup;
 import net.minecraft.core.component.DataComponentMap;
+import net.minecraft.tags.TagKey;
 import net.minecraft.world.item.Item;
 
 import net.fabricmc.fabric.api.event.Event;
@@ -101,6 +102,15 @@ default void modify(Item item, Consumer<DataComponentMap.Builder> builderConsume
 		default void modify(Collection<Item> items, BiConsumer<DataComponentMap.Builder, Item> builderConsumer) {
 			modify(items::contains, builderConsumer);
 		}
+
+		/**
+		 * Modify the default data components of the specified items.
+		 * @param tag The tag with items to modify
+		 * @param builderConsumer A consumer that provides a {@link DataComponentMap.Builder} to modify the item's components.
+		 */
+		default void modify(TagKey<Item> tag, BiConsumer<DataComponentMap.Builder, Item> builderConsumer) {
+			modify(item -> item.builtInRegistryHolder().is(tag), builderConsumer);
+		}
 	}
 
 	@FunctionalInterface

fabric-permission-api-v1/build.gradle

@@ -0,0 +1,14 @@
+version = getSubprojectVersion(project)
+
+loom {
+	accessWidenerPath = file('src/main/resources/fabric-permission-api-v1.classtweaker')
+}
+
+moduleDependencies(project, [
+	":fabric-api-base"
+])
+
+testDependencies(project, [
+	":fabric-command-api-v2",
+	":fabric-lifecycle-events-v1"
+])

fabric-permission-api-v1/src/main/java/net/fabricmc/fabric/api/permission/v1/MutablePermissionContext.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * 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.fabricmc.fabric.api.permission.v1;
+
+import org.jspecify.annotations.Nullable;
+
+/**
+ * Mutable version of {@link PermissionContext}, intended for creation of custom context conditions.
+ */
+public interface MutablePermissionContext extends PermissionContext {
+	<T> MutablePermissionContext set(PermissionContext.Key<T> key, @Nullable T value);
+}

fabric-permission-api-v1/src/main/java/net/fabricmc/fabric/api/permission/v1/PermissionContext.java

@@ -0,0 +1,247 @@
+/*
+ * Copyright (c) 2016, 2017, 2018, 2019 FabricMC
+ *
+ * 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.fabricmc.fabric.api.permission.v1;
+
+import java.util.Objects;
+import java.util.Set;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+
+import org.jetbrains.annotations.ApiStatus;
+import org.jspecify.annotations.Nullable;
+
+import net.minecraft.commands.CommandSourceStack;
+import net.minecraft.core.BlockPos;
+import net.minecraft.resources.Identifier;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.permissions.PermissionLevel;
+import net.minecraft.server.players.NameAndId;
+import net.minecraft.world.entity.Entity;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.phys.Vec3;
+
+import net.fabricmc.fabric.impl.permission.CustomPermissionContext;
+import net.fabricmc.fabric.impl.permission.OverriddenPermissionContext;
+import net.fabricmc.fabric.impl.permission.PermissionContextKey;
+
+/**
+ * Interface representing context object used for permission checks, providing both required
+ * and additional values.
+ *
+ * <p>Permission checks should be applied by calling methods defined in {@link PermissionContextOwner}
+ * For command checks, you can use {@link PermissionPredicates}.
+ */
+public interface PermissionContext extends PermissionContextOwner {
+	/**
+	 * Represents name attached to the permission context.
+	 * There is no requirement for it to be unique, as it might be changed by external factors.
+	 * Mainly used to help with identifying system-type contexts or context with shared/nil uuid.
+	 * For entities, it defaults to the plain name, based on either custom name or entity type name.
+	 */
+	Key<String> NAME = PermissionContextKey.NAME;
+
+	/**
+	 * Represents position current position in which permission check is applied.
+	 */
+	Key<Vec3> POSITION = PermissionContextKey.POSITION;
+
+	/**
+	 * Represents position current block position in which permission check is applied.
+	 */
+	Key<BlockPos> BLOCK_POSITION = PermissionContextKey.BLOCK_POSITION;
+
+	/**
+	 * Represents entity for which permission check is applied.
+	 */
+	Key<Entity> ENTITY = PermissionContextKey.ENTITY;
+
+	/**
+	 * Represents command source stack for which permission check is applied.
+	 */
+	Key<CommandSourceStack> COMMAND_SOURCE_STACK = PermissionContextKey.COMMAND_SOURCE_STACK;
+
+	/**
+	 * Represents level for which permission check is applied.
+	 */
+	Key<Level> LEVEL = PermissionContextKey.LEVEL;
+
+	/**
+	 * Represents the server to which this context is attached to.
+	 */
+	Key<MinecraftServer> SERVER = PermissionContextKey.SERVER;
+
+	/**
+	 * Creates a custom context, without any optional values.
+	 *
+	 * @param uuid the uuid connected to this context
+	 * @param type type of the context
+	 * @param permissionLevel base permission level
+	 * @return mutable permission context
+	 */
+	static MutablePermissionContext create(UUID uuid, Type type, PermissionLevel permissionLevel) {
+		Objects.requireNonNull(uuid, "uuid cannot be null");
+		Objects.requireNonNull(type, "type cannot be null");
+		Objects.requireNonNull(permissionLevel, "permissionLevel cannot be null");
+
+		return new CustomPermissionContext(uuid, type, permissionLevel);
+	}
+
+	/**
+	 * Creates a context of offline player.
+	 * Do note that depending on the backing implementation, the check for offline players
+	 * might be noticeably slower, so using async check methods or checking them on non-main threads
+	 * is encouraged.
+	 *
+	 * @param uuid player's uuid
+	 * @param server the currently running server instance
+	 * @return mutable permission context
+	 */
+	static CompletableFuture<MutablePermissionContext> offlinePlayer(UUID uuid, MinecraftServer server) {
+		Objects.requireNonNull(uuid, "uuid cannot be null");
+		Objects.requireNonNull(server, "server cannot be null");
+
+		PermissionLevel permissionLevel = server.getProfilePermissions(new NameAndId(uuid, "")).level();
+		var ctx = new CustomPermissionContext(uuid, Type.PLAYER, permissionLevel);
+		ctx.set(PermissionContext.SERVER, server);
+
+		return PermissionEvents.PREPARE_OFFLINE_PLAYER.invoker().prepareOfflinePlayer(ctx, server).thenApply(_ -> ctx);
+	}
+
+	/**
+	 * Creates a context of offline player.
+	 * Do note that depending on the backing implementation, the check for offline players
+	 * might be noticeably slower, so using async check methods or checking them on non-main threads
+	 * is encouraged.
+	 *
+	 * @param nameAndId player's name and uuid
+	 * @param server the currently running server instance
+	 * @return mutable permission context
+	 */
+	static CompletableFuture<MutablePermissionContext> offlinePlayer(NameAndId nameAndId, MinecraftServer server) {
+		Objects.requireNonNull(nameAndId, "nameAndId cannot be null");
+		Objects.requireNonNull(server, "server cannot be null");
+
+		PermissionLevel permissionLevel = server.getProfilePermissions(nameAndId).level();
+		var ctx = new CustomPermissionContext(nameAndId.id(), Type.PLAYER, permissionLevel);
+		ctx.set(PermissionContext.NAME, nameAndId.name());
+		ctx.set(PermissionContext.SERVER, server);
+
+		return PermissionEvents.PREPARE_OFFLINE_PLAYER.invoker().prepareOfflinePlayer(ctx, server).thenApply(_ -> ctx);
+	}
+
+	/**
+	 * Creates a unique key, indented for attaching additional context data.
+	 * This key/value can't be serialized.
+	 *
+	 * @param identifier unique identifier
+	 * @param <T> type of attached
+	 * @return unique key
+	 */
+	static <T> Key<T> key(Identifier identifier) {
+		Objects.requireNonNull(identifier, "identifier cannot be null");
+
+		return PermissionContextKey.getOrCreateKey(identifier);
+	}
+
+	/**
+	 * UUID connected to this context.
+	 */
+	UUID uuid();
+
+	/**
+	 * The type of the context.
+	 */
+	Type type();
+
+	/**
+	 * Returns optional value attached to this context.
+	 *
+	 * @param key unique key
+	 * @param <T> type of value
+	 * @return stored value if it's present, null otherwise
+	 */
+	@Nullable
+	<T> T get(Key<T> key);
+
+	/**
+	 * Returns optional value attached to this context, with a fallback.
+	 *
+	 * @param key unique key
+	 * @param defaultValue fallback value, if it's not present
+	 * @param <T> type of value
+	 * @return stored value if it's present, otherwise defaultValue
+	 */
+	default <T> T orElse(Key<T> key, T defaultValue) {
+		T value = get(key);
+
+		return value != null ? value : defaultValue;
+	}
+
+	/**
+	 * Creates a mutable copy of this context.
+	 *
+	 * @return a new mutable permission context.
+	 */
+	default MutablePermissionContext mutable() {
+		return new OverriddenPermissionContext(this);
+	}
+
+	/**
+	 * Provides the vanilla permission level of the context.
+	 *
+	 * @return permission level of the context.
+	 */
+	PermissionLevel permissionLevel();
+
+	/**
+	 * Provides a set of defined permission context keys.
+	 *
+	 * @return unmodifiable set of permission keys.
+	 */
+	Set<Key<?>> keys();
+
+	@Override
+	default PermissionContext getPermissionContext() {
+		return this;
+	}
+
+	/**
+	 * Identifies the owner type of the permission context.
+	 */
+	enum Type {
+		PLAYER,
+		ENTITY,
+		SYSTEM,
+		OTHER
+	}
+
+	/**
+	 * Key used to represent additional permission context.
+	 * The context itself might be serializable, however it's not a strict requirement.
+	 *
+	 * @param <T> type of the context
+	 */
+	@ApiStatus.NonExtendable
+	interface Key<T> {
+		/**
+		 * Identifier representing this context.
+		 *
+		 * @return id of this key
+		 */
+		Identifier id();
+	}
+}