Add API methods and command tests for new ActionLog system

Integrate log commands with new log backend method
Implement paginated logs for all storage backends
2024-06-16 21:11:07 +01:00 · 2024-06-16 20:45:05 +01:00 · 2024-06-16 20:45:05 +01:00 · 2024-06-16 20:45:04 +01:00 · 2024-06-16 20:45:04 +01:00 · 2024-06-16 10:45:47 +01:00
896 changed files with 31700 additions and 8898 deletions
@@ -1,40 +0,0 @@
---
-name: 🐛  Bug report
-about: Report an issue or problem with the way LuckPerms is functioning.
-title: ''
-labels: 'type: issue'
-assignees: ''
-
---
-
-<!-- Before going any further, please check to see if your problem is fixed by updating to a newer version. The latest development builds can be obtained from https://luckperms.net/download -->
-
-### Description
-<!-- Please provide a short description of the issue in the space below. -->
-
-
-### Reproduction steps
-<!-- Please provide a clear list of steps we should follow in order to reproduce your issue in the space below. -->
-
-1. Open the config.yml file and set example to true.
-2. Restart the server
-3. Run /lp user example permission set x from the console
-4. See error
-
-
-### Expected behaviour
-<!-- Please provide a description of what you expected to happen. -->
-
-
-### Environment details
-<!-- Please provide details of your server environment in the space below. -->
-
-* Server type/version: `ExampleSpigot` running version `1.12.2` build `???`
-* LuckPerms version: `v???`
-
-<!-- If you think it would be helpful, please also include a "pastebin" of any relevant config files or log output. You should use https://gist.github.com/ to upload, then include the link below. -->
-
-
-### Any other relevant details
-<!-- Please include any other relevant details in the space below. -->
-
@@ -0,0 +1,63 @@
+name: 🐛  Bug report
+description: Report an issue or problem with the way LuckPerms is functioning.
+labels: ["type: issue"]
+body:
+  - type: markdown
+    attributes:
+      value: "Before going any further, please check to see if your problem is fixed by updating to a newer version. The latest development builds can be obtained from https://luckperms.net/download"
+  - type: textarea
+    id: description
+    attributes:
+      label: Description
+      description: Please provide a short description of the issue in the space below.
+      placeholder: Description goes here!
+    validations:
+      required: true
+  - type: textarea
+    id: reproduction-steps
+    attributes:
+      label: Reproduction Steps
+      description: Please provide a clear list of steps we should follow in order to reproduce your issue in the space below.
+      placeholder: List reproduction steps here, please!
+    validations:
+      required: true
+  - type: textarea
+    id: expected-behaviour
+    attributes:
+      label: Expected Behaviour
+      description: Please provide a description of what you expected to happen.
+      placeholder: Describe what you expected to happen here.
+    validations:
+      required: true
+  - type: input
+    id: server-info
+    attributes:
+      label: Server Details
+      description: Please provide a description of the server details, including type and specific version number.
+      placeholder: 'git-Paper-124 (MC: 1.17.1)'
+    validations:
+      required: true
+  - type: input
+    id: luckperms-version
+    attributes:
+      label: LuckPerms Version
+      description: Please provide the specific, precise version number of LuckPerms you are using to reproduce this bug.
+      placeholder: v5.3.70
+    validations:
+      required: true
+  - type: textarea
+    id: logs
+    attributes:
+      label: Logs and Configs
+      description: If you think it would be helpful, please also include a pastebin of any relevant config files or log output. You should use https://gist.github.com/ to upload, then include the link below. 
+      placeholder: https://gist.github.com/HelpfulBugReporter/ThisIsAVeryUsefulLogOutput
+    validations:
+      required: false
+  - type: textarea
+    id: extra-info
+    attributes:
+      label: Extra Details
+      description: Please include any other relevant details in the space below.
+      placeholder: I was able to reproduce this only at the end of a rainbow.
+    validations:
+      required: false
@@ -1,16 +0,0 @@
---
-name: 💡  Suggestion
-about: Suggest an idea for an improvement or change to LuckPerms.
-title: ''
-labels: 'type: suggestion'
-assignees: ''
-
---
-
-### Description
-<!-- Please provide a short description of the suggestion in the space below. -->
-
-
-### Proposed behaviour
-<!-- Please provide a short explanation of how the feature should work / be changed, and how this will effect the project. -->
-
@@ -0,0 +1,31 @@
+name: 💡  Suggestion
+description: Suggest an idea for an improvement or change to LuckPerms.
+labels: ["type: suggestion"]
+body:
+  - type: markdown
+    attributes:
+      value: "Before going any further, please check to see if your suggestion has already been added by checking the [wiki](https://luckperms.net/wiki/Home). The latest development builds can be obtained from https://luckperms.net/download"
+  - type: textarea
+    id: description
+    attributes:
+      label: Description
+      description: Please provide a short description of your suggestion in the space below.
+      placeholder: Hello, perhaps you should...
+    validations:
+      required: true
+  - type: textarea
+    id: proposed-behaviour
+    attributes:
+      label: Proposed Behaviour
+      description: Please provide a short explanation of how the feature should work / be changed, and how this will affect the project.
+      placeholder: It would...
+    validations:
+      required: true
+  - type: textarea
+    id: extra-info
+    attributes:
+      label: Extra Details
+      description: Please include any other relevant details in the space below.
+      placeholder: I think this should only function at the end of a rainbow.
+    validations:
+      required: false
@@ -0,0 +1,130 @@
+name: Build Gradle and Publish Docker image
+
+on:
+  push:
+    branches:
+      - 'master'
+    tags:
+      - 'v*'
+  pull_request:
+    branches:
+      - 'master'
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  build-gradle:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - name: validate gradle wrapper
+        uses: gradle/wrapper-validation-action@v1
+
+      - uses: actions/setup-java@v3
+        with:
+          distribution: 'temurin'
+          java-version: '21'
+
+      - name: Setup Gradle
+        uses: gradle/gradle-build-action@v2
+
+      - name: Run build and tests with Gradle wrapper
+        run: ./gradlew test build -PdockerTests
+
+      - name: Publish test report
+        uses: mikepenz/action-junit-report@v3
+        if: success() || failure()
+        with:
+          report_paths: '**/build/test-results/test/TEST-*.xml'
+          annotate_notice: true
+          detailed_summary: true
+
+      - name: Upload all artifacts
+        uses: actions/upload-artifact@v3
+        with:
+          name: jars
+          path: |
+            bukkit/loader/build/libs/LuckPerms-Bukkit-*.jar
+            bukkit-legacy/loader/build/libs/LuckPerms-Bukkit-Legacy-*.jar
+            bungee/loader/build/libs/LuckPerms-Bungee-*.jar
+            sponge/loader/build/libs/LuckPerms-Sponge-*.jar
+            nukkit/loader/build/libs/LuckPerms-Nukkit-*.jar
+            velocity/build/libs/LuckPerms-Velocity-*.jar
+            fabric/build/libs/LuckPerms-Fabric-*.jar
+            forge/loader/build/libs/LuckPerms-Forge-*.jar
+            standalone/loader/build/libs/LuckPerms-Standalone-*.jar
+
+      - name: Upload standalone artifact
+        uses: actions/upload-artifact@v3
+        with:
+          name: standalone-binary
+          path: standalone/loader/build/libs/LuckPerms-Standalone-*.jar
+
+
+  build-docker:
+    needs: build-gradle
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - name: Retrieve saved standalone jar artifact
+        uses: actions/download-artifact@v3
+        with:
+          name: standalone-binary
+          path: standalone/docker/
+
+      - name: Remove version number from jar artifact name
+        run: mv standalone/docker/LuckPerms-Standalone-*.jar standalone/docker/luckperms-standalone.jar
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v1
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v1
+
+      - name: Log in to the Container registry
+        uses: docker/login-action@v1
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Determine the LuckPerms version
+        run: |
+          echo "luckperms_version=$(git describe --tags | awk -F "-" '{print $1 "." $2}')" >> "$GITHUB_ENV"
+
+      - name: Extract metadata for Docker
+        id: meta
+        uses: docker/metadata-action@v3
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          flavor: |
+            latest=${{ github.ref == 'refs/heads/master' }}
+          tags: |
+            type=schedule
+            type=ref,event=branch
+            type=ref,event=tag
+            type=ref,event=pr
+            type=raw,enable=${{ github.ref == 'refs/heads/master' }},value=${{ env.luckperms_version }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v2
+        with:
+          context: standalone/docker/
+          platforms: linux/amd64,linux/arm64
+          push: ${{ github.event_name != 'pull_request' }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
@@ -1,3 +1,6 @@
+### LuckPerms Standalone ###
+standalone/loader/data/
+
 ### Gradle & IntelliJ ###
 .gradle/
 /.idea/
@@ -8,7 +8,7 @@ Before reporting a bug or issue, please make sure that the issue is actually bei

 If you're unsure, feel free to ask using the above resources BEFORE making a report.

-Bugs or issues should be reported using the [GitHub Issues tab](https://github.com/lucko/LuckPerms/issues).
+Bugs or issues should be reported using the [GitHub Issues tab](https://github.com/LuckPerms/LuckPerms/issues).

 ### :pencil: Want to contribute code?
 #### Pull Requests
@@ -23,4 +23,4 @@ The project is split up into a few separate modules.

 * **API** - The public, semantically versioned API used by other plugins wishing to integrate with and retrieve data from LuckPerms. This module (for the most part) does not contain any implementation itself, and is provided by the plugin.
 * **Common** - The common module contains most of the code which implements the respective LuckPerms plugins. This abstract module reduces duplicated code throughout the project.
-* **Bukkit, BungeeCord, Sponge, Nukkit, Velocity & Fabric** - Each use the common module to implement plugins on the respective server platforms.
+* **Bukkit, BungeeCord, Fabric, Forge, Nukkit, Sponge & Velocity** - Each use the common module to implement plugins on the respective server platforms.
@@ -1,4 +1,4 @@
-![](https://i.imgur.com/ToguFkQ.png "Banner")
+![](https://raw.githubusercontent.com/LuckPerms/branding/master/banner/banner.png "Banner")
 # LuckPerms
 [![Build Status](https://ci.lucko.me/job/LuckPerms/badge/icon)](https://ci.lucko.me/job/LuckPerms/)
 [![javadoc](https://javadoc.io/badge2/net.luckperms/api/javadoc.svg)](https://javadoc.io/doc/net.luckperms/api)
@@ -24,17 +24,23 @@ For more information, see the wiki article on [Why LuckPerms?](https://luckperms
 LuckPerms uses Gradle to handle dependencies & building.

 #### Requirements
-* Java 8 JDK or newer
+* Java 21 JDK or newer
 * Git

 #### Compiling from source
 ```sh
-git clone https://github.com/lucko/LuckPerms.git
+git clone https://github.com/LuckPerms/LuckPerms.git
 cd LuckPerms/
 ./gradlew build
 ```

-You can find the output jars in the `build/libs` directories.
+You can find the output jars in the `loader/build/libs` or `build/libs` directories.
+
+## Tests
+There are some automated tests which run during each build.
+
+* Unit tests are defined in [`common/src/test`](https://github.com/LuckPerms/LuckPerms/tree/master/common/src/test)
+* Integration tests are defined in [`standalone/src/test`](https://github.com/LuckPerms/LuckPerms/tree/master/standalone/src/test).

 ## Contributing
 #### Pull Requests
@@ -47,7 +53,7 @@ The project is split up into a few separate modules.

 * **API** - The public, semantically versioned API used by other plugins wishing to integrate with and retrieve data from LuckPerms. This module (for the most part) does not contain any implementation itself, and is provided by the plugin.
 * **Common** - The common module contains most of the code which implements the respective LuckPerms plugins. This abstract module reduces duplicated code throughout the project.
-* **Bukkit, BungeeCord, Sponge, Fabric, Nukkit & Velocity** - Each use the common module to implement plugins on the respective server platforms.
+* **Bukkit, BungeeCord, Fabric, Forge, Nukkit, Sponge & Velocity** - Each use the common module to implement plugins on the respective server platforms.

 ## License
-LuckPerms is licensed under the permissive MIT license. Please see [`LICENSE.txt`](https://github.com/lucko/LuckPerms/blob/master/LICENSE.txt) for more info.
+LuckPerms is licensed under the permissive MIT license. Please see [`LICENSE.txt`](https://github.com/LuckPerms/LuckPerms/blob/master/LICENSE.txt) for more info.
@@ -1,9 +1,15 @@
 group = 'net.luckperms'
-project.version = '5.3'
+project.version = '5.4'
+
+jar {
+    manifest {
+        attributes('Automatic-Module-Name': 'net.luckperms.api')
+    }
+}

 dependencies {
-    compileOnly 'org.checkerframework:checker-qual:3.8.0'
-    compileOnly 'org.jetbrains:annotations:20.1.0'
+    compileOnly 'org.checkerframework:checker-qual:3.21.2'
+    compileOnly 'org.jetbrains:annotations:23.1.0'
 }

 // Only used occasionally for deployment - not needed for normal builds.
@@ -17,87 +23,84 @@ if (project.hasProperty('sonatypeUsername') && project.hasProperty('sonatypePass
        options.encoding = 'UTF-8'
        options.charSet = 'UTF-8'
        options.links(
-                'https://docs.oracle.com/javase/8/docs/api/',
                'https://checkerframework.org/api/',
-                'https://javadoc.io/static/org.jetbrains/annotations/20.1.0/'
+                'https://javadoc.io/static/org.jetbrains/annotations/23.0.0/'
        )
        options.addStringOption('Xdoclint:none', '-quiet')
+        options.addStringOption('-since', '5.0,5.1,5.2,5.3,5.4,5.5')
+
+        if (JavaVersion.current() > JavaVersion.VERSION_1_8) {
+            options.links.add('https://docs.oracle.com/en/java/javase/11/docs/api/')
+        } else {
+            options.links.add('https://docs.oracle.com/javase/8/docs/api/')
+        }
    }

-    task javadocJar(type: Jar, dependsOn: javadoc) {
-        classifier 'javadoc'
-        from javadoc.destinationDir
+    java {
+        withJavadocJar()
+        withSourcesJar()
    }

-    task sourcesJar(type: Jar) {
-        classifier 'sources'
-        from sourceSets.main.allSource
-    }
-
-    artifacts {
-        archives javadocJar
-        archives sourcesJar
-    }
-
-    signing {
-        useGpgCmd()
-        sign configurations.archives
-    }
-
-    uploadArchives {
+    publishing {
        repositories {
-            mavenDeployer {
-                beforeDeployment { MavenDeployment deployment -> signing.signPom(deployment) }
+            maven {
+                def releasesRepoUrl = 'https://oss.sonatype.org/service/local/staging/deploy/maven2/'
+                def snapshotsRepoUrl = 'https://oss.sonatype.org/content/repositories/snapshots/'
+                url = version.endsWith('SNAPSHOT') ? snapshotsRepoUrl : releasesRepoUrl

-                repository(url: 'https://oss.sonatype.org/service/local/staging/deploy/maven2/') {
-                    authentication(userName: sonatypeUsername, password: sonatypePassword)
+                credentials {
+                    username sonatypeUsername
+                    password sonatypePassword
                }
+            }
+        }

-                snapshotRepository(url: 'https://oss.sonatype.org/content/repositories/snapshots/') {
-                    authentication(userName: sonatypeUsername, password: sonatypePassword)
-                }
+        publications {
+            mavenJava(MavenPublication) {
+                artifactId = 'api'
+
+                from components.java

                pom {
-                    project {
-                        name 'LuckPerms API'
-                        description 'A permissions plugin for Minecraft servers.'
-                        url 'https://luckperms.net'
+                    name = 'LuckPerms API'
+                    description = 'A permissions plugin for Minecraft servers.'
+                    url = 'https://luckperms.net'

-                        licenses {
-                            license {
-                                name 'MIT'
-                                url 'https://opensource.org/licenses/MIT'
-                            }
+                    licenses {
+                        license {
+                            name = 'MIT'
+                            url = 'https://opensource.org/licenses/MIT'
                        }
+                    }

-                        developers {
-                            developer {
-                                id 'lucko'
-                                name 'Luck'
-                                url 'https://lucko.me'
-                                email 'git@lucko.me'
-                            }
+                    developers {
+                        developer {
+                            id = 'lucko'
+                            name = 'Luck'
+                            url = 'https://lucko.me'
+                            email = 'git@lucko.me'
                        }
+                    }

-                        scm {
-                            connection 'scm:git:https://github.com/lucko/LuckPerms.git'
-                            developerConnection 'scm:git:git@github.com:lucko/LuckPerms.git'
-                            url 'https://github.com/lucko/LuckPerms'
-                        }
+                    scm {
+                        connection = 'scm:git:https://github.com/LuckPerms/LuckPerms.git'
+                        developerConnection = 'scm:git:git@github.com:LuckPerms/LuckPerms.git'
+                        url = 'https://github.com/LuckPerms/LuckPerms'
+                    }

-                        ciManagement {
-                            system 'Jenkins'
-                            url 'https://ci.lucko.me/job/LuckPerms'
-                        }
-
-                        issueManagement {
-                            system 'GitHub'
-                            url 'https://github.com/lucko/LuckPerms/issues'
-                        }
+                    issueManagement {
+                        system = 'GitHub'
+                        url = 'https://github.com/LuckPerms/LuckPerms/issues'
                    }
                }
            }
        }
    }
+
+    signing {
+        useGpgCmd()
+        sign publishing.publications.mavenJava
+        required = true
+    }
 }
 */
@@ -8,10 +8,11 @@
    <li><a target="_top" href="https://luckperms.net">Project Website</a></li>
    <li><a target="_top" href="https://luckperms.net/wiki/Developer-API">Wiki - API Introduction</a></li>
    <li><a target="_top" href="https://luckperms.net/wiki/Developer-API-Usage">Wiki - API Usage</a></li>
+    <li><a target="_top" href="https://github.com/LuckPerms/LuckPerms">Source Code</a></li>
 </ul>
 <h4>Maven</h4>
 <p>
-    The API artifact is deployed to Maven Central under
+    The API artifact is deployed to Maven Central with
    <a target="_top" href="https://search.maven.org/artifact/net.luckperms/api">
        group id: <b><code>net.luckperms</code></b>, artifact id: <b><code>api</code></b>.
    </a>
@@ -26,6 +26,7 @@
 package net.luckperms.api;

 import net.luckperms.api.actionlog.ActionLogger;
+import net.luckperms.api.actionlog.filter.ActionFilterFactory;
 import net.luckperms.api.context.ContextCalculator;
 import net.luckperms.api.context.ContextManager;
 import net.luckperms.api.event.EventBus;
@@ -40,13 +41,13 @@ import net.luckperms.api.model.user.User;
 import net.luckperms.api.model.user.UserManager;
 import net.luckperms.api.node.NodeBuilderRegistry;
 import net.luckperms.api.node.matcher.NodeMatcherFactory;
+import net.luckperms.api.platform.Health;
 import net.luckperms.api.platform.Platform;
 import net.luckperms.api.platform.PlayerAdapter;
 import net.luckperms.api.platform.PluginMetadata;
 import net.luckperms.api.query.QueryOptionsRegistry;
 import net.luckperms.api.track.Track;
 import net.luckperms.api.track.TrackManager;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.ApiStatus.Internal;

@@ -220,6 +221,17 @@ public interface LuckPerms {
     */
    @NonNull CompletableFuture<Void> runUpdateTask();

+    /**
+     * Executes a health check.
+     *
+     * <p>This task checks if the LuckPerms implementation is running and
+     * whether it has a connection to the database (if applicable).</p>
+     *
+     * @return the health status
+     * @since 5.5
+     */
+    @NonNull Health runHealthCheck();
+
    /**
     * Registers a {@link MessengerProvider} for use by the platform.
     *
@@ -256,4 +268,14 @@ public interface LuckPerms {
    @Internal
    @NonNull NodeMatcherFactory getNodeMatcherFactory();

+    /**
+     * Gets the {@link ActionFilterFactory}.
+     *
+     * @return the action filter factory
+     * @since 5.5
+     */
+    @Internal
+    @NonNull
+    ActionFilterFactory getActionFilterFactory();
+
 }
@@ -48,6 +48,7 @@ public final class LuckPermsProvider {
     * @throws IllegalStateException if the API is not loaded yet
     */
    public static @NonNull LuckPerms get() {
+        LuckPerms instance = LuckPermsProvider.instance;
        if (instance == null) {
            throw new NotLoadedException();
        }
@@ -76,9 +77,9 @@ public final class LuckPermsProvider {
        private static final String MESSAGE = "The LuckPerms API isn't loaded yet!\n" +
                "This could be because:\n" +
                "  a) the LuckPerms plugin is not installed or it failed to enable\n" +
-                "  b) your plugin does not declare a dependency on LuckPerms\n" +
-                "  c) you are attempting to use the API before plugins reach the 'enable' phase\n" +
-                "     (call the #get method in onEnable, not in your plugin constructor!)\n";
+                "  b) the plugin in the stacktrace does not declare a dependency on LuckPerms\n" +
+                "  c) the plugin in the stacktrace is retrieving the API before the plugin 'enable' phase\n" +
+                "     (call the #get method in onEnable, not the constructor!)\n";

        NotLoadedException() {
            super(MESSAGE);
@@ -26,9 +26,9 @@
 package net.luckperms.api.actionlog;

 import net.luckperms.api.LuckPermsProvider;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
+import org.jetbrains.annotations.ApiStatus.NonExtendable;

 import java.time.Instant;
 import java.util.Optional;
@@ -36,7 +36,10 @@ import java.util.UUID;

 /**
 * Represents a logged action.
+ *
+ * <p>API users should not implement this interface directly.</p>
 */
+@NonExtendable
 public interface Action extends Comparable<Action> {

    /**
@@ -82,6 +85,7 @@ public interface Action extends Comparable<Action> {
    /**
     * Represents the source of an action.
     */
+    @NonExtendable
    interface Source {

        /**
@@ -103,6 +107,7 @@ public interface Action extends Comparable<Action> {
    /**
     * Represents the target of an action.
     */
+    @NonExtendable
    interface Target {

        /**
@@ -127,7 +132,7 @@ public interface Action extends Comparable<Action> {
        @NonNull Type getType();

        /**
-         * Represents the type of a {@link Target}.
+         * Represents the type of {@link Target}.
         */
        enum Type {
            USER, GROUP, TRACK
@@ -170,7 +175,7 @@ public interface Action extends Comparable<Action> {
         * @param type the type
         * @return the builder
         */
-        @NonNull Builder targetType(Action.Target.Type type);
+        @NonNull Builder targetType(Target.@NonNull Type type);

        /**
         * Sets the acted object for the entry.
@@ -25,6 +25,7 @@

 package net.luckperms.api.actionlog;

+import net.luckperms.api.actionlog.filter.ActionFilter;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -40,7 +41,11 @@ import java.util.UUID;
 * You can add to the log using the {@link ActionLogger}, and then request an updated copy.</p>
 *
 * <p>All methods are thread safe, and return immutable and thread safe collections.</p>
+ *
+ * @deprecated Use {@link ActionLogger#queryActions(ActionFilter)} or
+ * {@link ActionLogger#queryActions(ActionFilter, int, int)} instead.
 */
+@Deprecated
 public interface ActionLog {

    /**
@@ -25,10 +25,11 @@

 package net.luckperms.api.actionlog;

-import net.luckperms.api.messaging.MessagingService;
-
+import net.luckperms.api.actionlog.filter.ActionFilter;
+import net.luckperms.api.util.Page;
 import org.checkerframework.checker.nullness.qual.NonNull;

+import java.util.List;
 import java.util.concurrent.CompletableFuture;

 /**
@@ -47,43 +48,78 @@ public interface ActionLogger {
     * Gets a {@link ActionLog} instance from the plugin storage.
     *
     * @return a log instance
+     * @deprecated Use {@link #queryActions(ActionFilter)} or {@link #queryActions(ActionFilter, int, int)} instead. These methods
+     * are more efficient (they don't load the full action log into memory) and allow for pagination.
     */
+    @Deprecated
    @NonNull CompletableFuture<ActionLog> getLog();

    /**
-     * Submits a log entry to the plugin to be handled.
+     * Gets all actions from the action log matching the given {@code filter}.
     *
-     * <p>This method submits the log to the storage provider and broadcasts
-     * it.</p>
+     * <p>If the filter is {@code null}, all actions will be returned.</p>
     *
-     * <p>It is therefore roughly equivalent to calling
-     * {@link #submitToStorage(Action)} and {@link #broadcastAction(Action)},
-     * however, using this method is preferred to making the calls individually.</p>
+     * <p>Unlike {@link #queryActions(ActionFilter, int, int)}, this method does not implement any pagination and will return
+     * all entries at once.</p>
     *
-     * <p>If you want to submit a log entry but don't know which method to pick,
+     * @param filter the filter, optional
+     * @return the actions
+     * @since 5.5
+     */
+    @NonNull CompletableFuture<List<Action>> queryActions(@NonNull ActionFilter filter);
+
+    /**
+     * Gets a page of actions from the action log matching the given {@code filter}.
+     *
+     * <p>If the filter is {@code null}, all actions will be returned.</p>
+     *
+     * @param filter the filter, optional
+     * @param pageSize the size of the page
+     * @param pageNumber the page number
+     * @return the page of actions
+     * @since 5.5
+     */
+    @NonNull CompletableFuture<Page<Action>> queryActions(@NonNull ActionFilter filter, int pageSize, int pageNumber);
+
+    /**
+     * Submits a logged action to LuckPerms.
+     *
+     * <p>This method submits the action to the storage provider to be persisted in the action log.
+     * It also broadcasts it to administrator players on the current instance and to admins on other
+     * connected servers if a messaging service is configured.</p>
+     *
+     * <p>It is roughly equivalent to calling
+     * {@link #submitToStorage(Action)} followed by {@link #broadcastAction(Action)},
+     * however using this method is preferred to making the calls individually.</p>
+     *
+     * <p>If you want to submit an action log entry but don't know which method to pick,
     * use this one.</p>
     *
     * @param entry the entry to submit
-     * @return a future which will complete when the action is done
+     * @return a future which will complete when the action is submitted
     */
    @NonNull CompletableFuture<Void> submit(@NonNull Action entry);

    /**
-     * Submits a log entry to the plugins storage handler.
+     * Submits a logged action to LuckPerms and persists it in the storage backend.
+     *
+     * <p>This method does not broadcast the action or send it through the messaging service.</p>
     *
     * @param entry the entry to submit
-     * @return a future which will complete when the action is done
+     * @return a future which will complete when the action is submitted
     */
    @NonNull CompletableFuture<Void> submitToStorage(@NonNull Action entry);

    /**
-     * Submits a log entry to the plugins log broadcasting handler.
+     * Submits a logged action to LuckPerms and broadcasts it to administrators.
     *
-     * <p>If enabled, this method will also dispatch the log entry via the
-     * plugins {@link MessagingService}.</p>
+     * <p>The broadcast is made to administrator players on the current instance
+     * and to admins on other connected servers if a messaging service is configured.</p>
+     *
+     * <p>This method does not save the action to the plugin storage backend.</p>
     *
     * @param entry the entry to submit
-     * @return a future which will complete when the action is done
+     * @return a future which will complete when the action is broadcasted
     */
    @NonNull CompletableFuture<Void> broadcastAction(@NonNull Action entry);

@@ -0,0 +1,114 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.api.actionlog.filter;
+
+import net.luckperms.api.LuckPermsProvider;
+import net.luckperms.api.actionlog.Action;
+import org.jetbrains.annotations.ApiStatus.NonExtendable;
+
+import java.util.UUID;
+import java.util.function.Predicate;
+
+/**
+ * A predicate filter which matches certain {@link Action}s.
+ *
+ * <p>API users should not implement this interface directly.</p>
+ *
+ * @since 5.5
+ */
+@NonExtendable
+public interface ActionFilter extends Predicate<Action> {
+
+    /**
+     * Gets an {@link ActionFilter} which matches any action.
+     *
+     * @return the matcher
+     */
+    static ActionFilter any() {
+        return LuckPermsProvider.get().getActionFilterFactory().any();
+    }
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions with a specific source user.
+     *
+     * @param uniqueId the source user unique id
+     * @return the matcher
+     */
+    static ActionFilter source(UUID uniqueId) {
+        return LuckPermsProvider.get().getActionFilterFactory().source(uniqueId);
+    }
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions which target a specific user.
+     *
+     * @param uniqueId the target user unique id
+     * @return the matcher
+     */
+    static ActionFilter user(UUID uniqueId) {
+        return LuckPermsProvider.get().getActionFilterFactory().user(uniqueId);
+    }
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions which target a specific group.
+     *
+     * @param name the target group name
+     * @return the matcher
+     */
+    static ActionFilter group(String name) {
+        return LuckPermsProvider.get().getActionFilterFactory().group(name);
+    }
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions which target a specific track.
+     *
+     * @param name the target track name
+     * @return the matcher
+     */
+    static ActionFilter track(String name) {
+        return LuckPermsProvider.get().getActionFilterFactory().track(name);
+    }
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions which contain a specific search query in the source name,
+     * target name or description.
+     *
+     * @param query the search query
+     * @return the matcher
+     */
+    static ActionFilter search(String query) {
+        return LuckPermsProvider.get().getActionFilterFactory().search(query);
+    }
+
+    /**
+     * Tests to see if the given {@link Action} matches the filter.
+     *
+     * @param action the action to test
+     * @return true if the action matched
+     */
+    @Override
+    boolean test(Action action);
+
+}
@@ -0,0 +1,88 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.api.actionlog.filter;
+
+import org.jetbrains.annotations.ApiStatus.Internal;
+
+import java.util.UUID;
+
+/**
+ * A factory which creates {@link ActionFilter}s.
+ *
+ * @since 5.5
+ */
+@Internal
+public interface ActionFilterFactory {
+
+    /**
+     * Gets an {@link ActionFilter} which matches any action.
+     *
+     * @return the matcher
+     */
+    ActionFilter any();
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions with a specific source user.
+     *
+     * @param uniqueId the source user unique id
+     * @return the matcher
+     */
+    ActionFilter source(UUID uniqueId);
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions which target a specific user.
+     *
+     * @param uniqueId the target user unique id
+     * @return the matcher
+     */
+    ActionFilter user(UUID uniqueId);
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions which target a specific group.
+     *
+     * @param name the target group name
+     * @return the matcher
+     */
+    ActionFilter group(String name);
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions which target a specific track.
+     *
+     * @param name the target track name
+     * @return the matcher
+     */
+    ActionFilter track(String name);
+
+    /**
+     * Gets an {@link ActionFilter} which matches actions which contain a specific search query in the source name,
+     * target name or description.
+     *
+     * @param query the search query
+     * @return the matcher
+     */
+    ActionFilter search(String query);
+
+}
@@ -0,0 +1,29 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+/**
+ * {@link net.luckperms.api.actionlog.Action} filters.
+ */
+package net.luckperms.api.actionlog.filter;
@@ -26,11 +26,14 @@
 package net.luckperms.api.cacheddata;

 import net.luckperms.api.query.QueryOptions;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
 * Holds cached lookup data for a given set of query options.
+ *
+ * <p>All calls will account for inheritance, as well as any default data
+ * provided by the platform. These calls are heavily cached and are therefore
+ * fast.</p>
 */
 public interface CachedData {

@@ -30,7 +30,6 @@ import net.luckperms.api.model.PermissionHolder;
 import net.luckperms.api.model.group.Group;
 import net.luckperms.api.model.user.User;
 import net.luckperms.api.query.QueryOptions;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.concurrent.CompletableFuture;
@@ -39,7 +38,7 @@ import java.util.concurrent.CompletableFuture;
 * Holds cached permission and meta lookup data for a {@link PermissionHolder}.
 *
 * <p>All calls will account for inheritance, as well as any default data
- * provided by the platform. This calls are heavily cached and are therefore
+ * provided by the platform. These calls are heavily cached and are therefore
 * fast.</p>
 */
 public interface CachedDataManager {
@@ -81,11 +80,10 @@ public interface CachedDataManager {
     * <p>For {@link User}s, the most appropriate query options will be their
     * {@link ContextManager#getQueryOptions(User) current active query options} if the
     * corresponding player is online, and otherwise, will fallback to
-     * {@link ContextManager#getStaticQueryOptions() the current static query options}
-     * if they are offline.</p>
+     * {@link ContextManager#getStaticQueryOptions() the current static query options}.</p>
     *
     * <p>For {@link Group}s, the most appropriate query options will always be
-     * {@link ContextManager#getStaticQueryOptions()} the current static query options.</p>
+     * {@link ContextManager#getStaticQueryOptions() the current static query options}.</p>
     *
     * @return a permission data instance
     * @since 5.1
@@ -99,11 +97,10 @@ public interface CachedDataManager {
     * <p>For {@link User}s, the most appropriate query options will be their
     * {@link ContextManager#getQueryOptions(User) current active query options} if the
     * corresponding player is online, and otherwise, will fallback to
-     * {@link ContextManager#getStaticQueryOptions() the current static query options}
-     * if they are offline.</p>
+     * {@link ContextManager#getStaticQueryOptions() the current static query options}.</p>
     *
     * <p>For {@link Group}s, the most appropriate query options will always be
-     * {@link ContextManager#getStaticQueryOptions()} the current static query options.</p>
+     * {@link ContextManager#getStaticQueryOptions() the current static query options}.</p>
     *
     * @return a meta data instance
     * @since 5.1
@@ -118,7 +115,7 @@ public interface CachedDataManager {
    void invalidate();

    /**
-     * Invalidates all of the underlying Permission calculators.
+     * Invalidates all underlying permission calculators.
     *
     * <p>Can be called to allow for an update in defaults.</p>
     */
@@ -26,7 +26,10 @@
 package net.luckperms.api.cacheddata;

 import net.luckperms.api.metastacking.MetaStackDefinition;
-
+import net.luckperms.api.node.types.MetaNode;
+import net.luckperms.api.node.types.PrefixNode;
+import net.luckperms.api.node.types.SuffixNode;
+import net.luckperms.api.node.types.WeightNode;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.Unmodifiable;
@@ -39,16 +42,40 @@ import java.util.function.Function;

 /**
 * Holds cached meta lookup data for a specific set of contexts.
+ * 
+ * <p>Meta data refers to {@link PrefixNode prefixes}, {@link SuffixNode suffixes} and
+ * {@link MetaNode meta (options)} held by a permission holder.</p>
+ *
+ * <p>All calls will account for inheritance, as well as any default data
+ * provided by the platform. These calls are heavily cached and are therefore
+ * fast.</p>
 */
 public interface CachedMetaData extends CachedData {

+    /**
+     * Query a meta value for the given {@code key}.
+     * 
+     * <p>This method will always return a {@link Result}, but the
+     * {@link Result#result() inner result} {@link String} will be null if a value
+     * for the given key was not found.</p>
+     *
+     * @param key the key
+     * @return a result containing the value
+     * @since 5.4
+     */
+    @NonNull Result<String, MetaNode> queryMetaValue(@NonNull String key);
+
    /**
     * Gets a value for the given meta key.
+     * 
+     * <p>If no such meta value exists for the given key, {@code null} is returned.</p>
     *
     * @param key the key
     * @return the value
     */
-    @Nullable String getMetaValue(@NonNull String key);
+    default @Nullable String getMetaValue(@NonNull String key) {
+        return queryMetaValue(key).result();
+    }

    /**
     * Gets a value for the given meta key, and runs it through the given {@code transformer}.
@@ -81,37 +108,121 @@ public interface CachedMetaData extends CachedData {
    }

    /**
-     * Gets the holder's highest priority prefix, or null if the holder has no prefixes
+     * Query for a prefix.
+     * 
+     * <p>This method uses the rules defined by the {@link #getPrefixStackDefinition() prefix stack}
+     * to produce a {@link String} output.</p>
+     * 
+     * <p>Assuming the default configuration is used, this will usually be the value of the
+     * holder's highest priority prefix node.</p>
+     * 
+     * <p>This method will always return a {@link Result}, but the
+     * {@link Result#result() inner result} {@link String} will be null if
+     * a the resultant prefix stack contained no elements.</p>
+     *
+     * @return a result containing the prefix
+     * @since 5.4
+     */
+    @NonNull Result<String, PrefixNode> queryPrefix();
+
+    /**
+     * Gets the prefix.
+     * 
+     * <p>This method uses the rules defined by the {@link #getPrefixStackDefinition() prefix stack}
+     * to produce a {@link String} output.</p>
+     * 
+     * <p>Assuming the default configuration is used, this will usually be the value of the
+     * holder's highest priority prefix node.</p>
+     * 
+     * <p>If the resultant prefix stack contained no elements, {@code null} is returned.</p>
     *
     * @return a prefix string, or null
     */
-    @Nullable String getPrefix();
+    default @Nullable String getPrefix() {
+        return queryPrefix().result();
+    }

    /**
-     * Gets the holder's highest priority suffix, or null if the holder has no suffixes
+     * Query for a suffix.
+     *
+     * <p>This method uses the rules defined by the {@link #getSuffixStackDefinition() suffix stack}
+     * to produce a {@link String} output.</p>
+     *
+     * <p>Assuming the default configuration is used, this will usually be the value of the
+     * holder's highest priority suffix node.</p>
+     *
+     * <p>This method will always return a {@link Result}, but the
+     * {@link Result#result() inner result} {@link String} will be null if
+     * a the resultant suffix stack contained no elements.</p>
+     *
+     * @return a result containing the suffix
+     * @since 5.4
+     */
+    @NonNull Result<String, SuffixNode> querySuffix();
+
+    /**
+     * Gets the suffix.
+     *
+     * <p>This method uses the rules defined by the {@link #getSuffixStackDefinition() suffix stack}
+     * to produce a {@link String} output.</p>
+     *
+     * <p>Assuming the default configuration is used, this will usually be the value of the
+     * holder's highest priority suffix node.</p>
+     *
+     * <p>If the resultant suffix stack contained no elements, {@code null} is returned.</p>
     *
     * @return a suffix string, or null
     */
-    @Nullable String getSuffix();
+    default @Nullable String getSuffix() {
+        return querySuffix().result();
+    }

    /**
-     * Gets an immutable copy of the meta this holder has.
+     * Query for a weight.
     *
-     * @return an immutable map of meta
+     * <p>This method will always return a {@link Result}, and the
+     * {@link Result#result() inner result} {@link Integer} will never be null.
+     * A value of {@code 0} is equivalent to null.</p>
+     *
+     * @return a result containing the weight
+     * @since 5.5
+     */
+    @NonNull Result<Integer, WeightNode> queryWeight();
+
+    /**
+     * Gets the weight.
+     *
+     * <p>If the there is no defined weight, {@code 0} is returned.</p>
+     *
+     * @return the weight
+     * @since 5.5
+     */
+    default int getWeight() {
+        return queryWeight().result();
+    }
+
+    /**
+     * Gets a map of all accumulated {@link MetaNode meta}.
+     *
+     * <p>Prefer using the {@link #getMetaValue(String)} method for querying values.</p>
+     *
+     * @return a map of meta
     */
    @NonNull @Unmodifiable Map<String, List<String>> getMeta();

    /**
-     * Gets an immutable sorted map of all of the prefixes the holder has, whereby the first
-     * value is the highest priority prefix.
+     * Gets a sorted map of all accumulated {@link PrefixNode prefixes}.
+     *
+     * <p>Prefer using the {@link #getPrefix()} method for querying.</p>
     *
     * @return a sorted map of prefixes
     */
    @NonNull @Unmodifiable SortedMap<Integer, String> getPrefixes();

    /**
-     * Gets an immutable sorted map of all of the suffixes the holder has, whereby the first
-     * value is the highest priority suffix.
+     * Gets a sorted map of all accumulated {@link SuffixNode suffixes}.
+     *
+     * <p>Prefer using the {@link #getSuffix()} method for querying.</p>
     *
     * @return a sorted map of suffixes
     */
@@ -128,14 +239,14 @@ public interface CachedMetaData extends CachedData {
    @Nullable String getPrimaryGroup();

    /**
-     * Gets the definition used for the prefix stack
+     * Gets the definition used for the prefix stack.
     *
     * @return the definition used for the prefix stack
     */
    @NonNull MetaStackDefinition getPrefixStackDefinition();

    /**
-     * Gets the definition used for the suffix stack
+     * Gets the definition used for the suffix stack.
     *
     * @return the definition used for the suffix stack
     */
@@ -25,8 +25,8 @@

 package net.luckperms.api.cacheddata;

+import net.luckperms.api.node.Node;
 import net.luckperms.api.util.Tristate;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -34,17 +34,39 @@ import java.util.Map;

 /**
 * Holds cached permission lookup data for a specific set of contexts.
+ *
+ * <p>All calls will account for inheritance, as well as any default data
+ * provided by the platform. These calls are heavily cached and are therefore
+ * fast.</p>
 */
 public interface CachedPermissionData extends CachedData {

    /**
-     * Gets a permission check result for the given permission node.
+     * Performs a permission check for the given {@code permission} node.
+     *
+     * <p>This check is equivalent to the "hasPermission" method call on most platforms.
+     * You can use {@link Tristate#asBoolean()} if you need a truthy result.</p>
+     *
+     * @param permission the permission node
+     * @return a result containing the tristate
+     * @throws NullPointerException if permission is null
+     * @since 5.4
+     */
+    @NonNull Result<Tristate, Node> queryPermission(@NonNull String permission);
+
+    /**
+     * Performs a permission check for the given {@code permission} node.
+     *
+     * <p>This check is equivalent to the "hasPermission" method call on most platforms.
+     * You can use {@link Tristate#asBoolean()} if you need a truthy result.</p>
     *
     * @param permission the permission node
     * @return a tristate result
     * @throws NullPointerException if permission is null
     */
-    @NonNull Tristate checkPermission(@NonNull String permission);
+    default @NonNull Tristate checkPermission(@NonNull String permission) {
+        return queryPermission(permission).result();
+    }

    /**
     * Invalidates the underlying permission calculator cache.
@@ -0,0 +1,81 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.api.cacheddata;
+
+import net.luckperms.api.node.Node;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+/**
+ * Represents the result of a cached data lookup.
+ *
+ * <p>You can find "the holder that has the node that caused this result"
+ * using the following code:</p>
+ * <p></p>
+ * <blockquote>
+ * <pre>
+ * public static {@link net.luckperms.api.model.PermissionHolder.Identifier} holderThatHasTheNodeThatCausedTheResult(Result&lt;?, ?&gt; result) {
+ *     {@link Node} node = result.node();
+ *     if (node == null) {
+ *         return null;
+ *     }
+ *     {@link net.luckperms.api.node.metadata.types.InheritanceOriginMetadata} origin = node.getMetadata(InheritanceOriginMetadata.KEY).orElse(null);
+ *     if (origin == null) {
+ *         return null;
+ *     }
+ *     return origin.getOrigin();
+ * }
+ * </pre>
+ *
+ * <p>Combined with the node itself, this is all the information needed to determine
+ * the root cause of the result.</p>
+ * </blockquote>
+ *
+ * <p>The nullability of {@link #result()} is purposely undefined to allow the
+ * flexibility for methods using {@link Result} to declare it. In general, if the {@code T} type
+ * has a nullable/undefined value, then the return of {@link #result()} will be non-null,
+ * and if not, it will be nullable.</p>
+ *
+ * @param <T> the result type
+ * @param <N> the node type
+ * @since 5.4
+ */
+public interface Result<T, N extends Node> {
+
+    /**
+     * Gets the underlying result.
+     *
+     * @return the underlying result
+     */
+    T result();
+
+    /**
+     * Gets the node that caused the result.
+     *
+     * @return the causing node
+     */
+    @Nullable N node();
+
+}
@@ -24,7 +24,7 @@
 */

 /**
- * CachedData lookup API for {@link net.luckperms.api.model.user.User}s and
+ * Caches permission checks and meta lookups for {@link net.luckperms.api.model.user.User}s and
 * {@link net.luckperms.api.model.group.Group}s.
 */
 package net.luckperms.api.cacheddata;
@@ -103,7 +103,7 @@ public interface ContextCalculator<T> {
     *
     * @return a set of potential contexts
     */
-    default ContextSet estimatePotentialContexts() {
+    default @NonNull ContextSet estimatePotentialContexts() {
        return ImmutableContextSet.empty();
    }

@@ -28,7 +28,6 @@ package net.luckperms.api.context;
 import net.luckperms.api.model.user.User;
 import net.luckperms.api.query.QueryMode;
 import net.luckperms.api.query.QueryOptions;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.ApiStatus.Internal;

@@ -26,7 +26,6 @@
 package net.luckperms.api.context;

 import net.luckperms.api.LuckPermsProvider;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.Objects;
@@ -119,7 +118,7 @@ public interface ImmutableContextSet extends ContextSet {
        }

        /**
-         * Adds of of the contexts in another {@link ContextSet} to the set.
+         * Adds all the contexts in another {@link ContextSet} to the set.
         *
         * @param contextSet the set to add from
         * @return the builder
@@ -26,7 +26,6 @@
 package net.luckperms.api.context;

 import net.luckperms.api.LuckPermsProvider;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.Objects;
@@ -94,7 +93,7 @@ public interface MutableContextSet extends ContextSet {
    }

    /**
-     * Adds of of the contexts in another {@link ContextSet} to this set.
+     * Adds all the contexts in another {@link ContextSet} to this set.
     *
     * @param contextSet the set to add from
     * @throws NullPointerException if the contextSet is null
@@ -26,7 +26,6 @@
 package net.luckperms.api.event;

 import net.luckperms.api.LuckPerms;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -28,7 +28,6 @@ package net.luckperms.api.event.context;
 import net.luckperms.api.context.ContextManager;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.Optional;
@@ -28,7 +28,6 @@ package net.luckperms.api.event.extension;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.extension.Extension;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.cacheddata.CachedDataManager;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.group.Group;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.cause.CreationCause;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.group.Group;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.cacheddata.CachedDataManager;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.group.Group;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.cause.DeletionCause;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.node.Node;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.Set;
@@ -28,7 +28,6 @@ package net.luckperms.api.event.group;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.group.Group;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.actionlog.Action;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.Cancellable;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.actionlog.Action;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.Cancellable;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.UUID;
@@ -30,7 +30,6 @@ import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.Cancellable;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.platform.PlatformEntity;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.actionlog.Action;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.Cancellable;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -28,13 +28,16 @@ package net.luckperms.api.event.log;
 import net.luckperms.api.actionlog.Action;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.UUID;

 /**
- * Called when a log entry is received via the MessagingService
+ * Called when a log entry is received via the MessagingService.
+ *
+ * <p>Note: listening to this event is the same as listening to the {@link LogBroadcastEvent}
+ * and filtering for {@link LogBroadcastEvent#getOrigin() origin} =
+ * {@link net.luckperms.api.event.log.LogBroadcastEvent.Origin#REMOTE REMOTE}.</p>
 */
 public interface LogReceiveEvent extends LuckPermsEvent {

@@ -0,0 +1,59 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.api.event.messaging;
+
+import net.luckperms.api.event.LuckPermsEvent;
+import net.luckperms.api.event.util.Param;
+import net.luckperms.api.messaging.MessagingService;
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+/**
+ * Called when a custom payload message is received via the {@link MessagingService}.
+ *
+ * <p>This event is effectively the 'other end' of
+ * {@link MessagingService#sendCustomMessage(String, String)}.</p>
+ *
+ * @since 5.5
+ */
+public interface CustomMessageReceiveEvent extends LuckPermsEvent {
+
+    /**
+     * Gets the channel id.
+     *
+     * @return the channel id
+     */
+    @Param(0)
+    @NonNull String getChannelId();
+
+    /**
+     * Gets the custom payload that was sent.
+     *
+     * @return the custom payload
+     */
+    @Param(1)
+    @NonNull String getPayload();
+
+}
@@ -0,0 +1,29 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+/**
+ * Events relating to the {@link net.luckperms.api.messaging.MessagingService}.
+ */
+package net.luckperms.api.event.messaging;
@@ -27,7 +27,6 @@ package net.luckperms.api.event.node;

 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.node.Node;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -27,7 +27,6 @@ package net.luckperms.api.event.node;

 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.node.Node;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -32,7 +32,6 @@ import net.luckperms.api.model.data.DataType;
 import net.luckperms.api.model.group.Group;
 import net.luckperms.api.model.user.User;
 import net.luckperms.api.node.Node;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -27,7 +27,6 @@ package net.luckperms.api.event.node;

 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.node.Node;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -29,7 +29,6 @@ import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.PlayerSaveResult;
 import net.luckperms.api.model.user.UserManager;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.UUID;
@@ -29,7 +29,6 @@ import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.user.User;
 import net.luckperms.api.util.Result;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;

@@ -28,7 +28,6 @@ package net.luckperms.api.event.player.lookup;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.ResultEvent;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.Objects;
@@ -56,6 +55,22 @@ public interface UniqueIdDetermineTypeEvent extends LuckPermsEvent, ResultEvent<
     */
    String TYPE_UNAUTHENTICATED = "unauthenticated";

+    /**
+     * The players UUID most likely belongs to a NPC (non-player character).
+     *
+     * <p>Usually indicated by the UUID being {@link UUID#version() version} 2.</p>
+     *
+     * @since 5.4
+     */
+    String TYPE_NPC = "npc";
+
+    /**
+     * Unknown UUID type.
+     *
+     * @since 5.4
+     */
+    String TYPE_UNKNOWN = "unknown";
+
    /**
     * Gets the {@link UUID unique id} being queried.
     *
@@ -28,7 +28,6 @@ package net.luckperms.api.event.player.lookup;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.ResultEvent;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;

@@ -28,7 +28,6 @@ package net.luckperms.api.event.player.lookup;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.ResultEvent;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;

@@ -27,7 +27,6 @@ package net.luckperms.api.event.player.lookup;

 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.concurrent.atomic.AtomicBoolean;
@@ -26,7 +26,6 @@
 package net.luckperms.api.event.source;

 import net.luckperms.api.platform.PlatformEntity;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -26,7 +26,6 @@
 package net.luckperms.api.event.source;

 import net.luckperms.api.platform.PlatformEntity;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -0,0 +1,81 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.api.event.sync;
+
+import net.luckperms.api.event.LuckPermsEvent;
+import net.luckperms.api.event.util.Param;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+import java.util.UUID;
+
+/**
+ * Called after a network synchronisation task has been completed.
+ *
+ * <p>Note: the generic {@link PostSyncEvent} will also be called for {@link SyncType#FULL full syncs}.</p>
+ *
+ * @since 5.5
+ */
+public interface PostNetworkSyncEvent extends LuckPermsEvent {
+
+    /**
+     * Gets the ID of the sync request
+     *
+     * @return the id of the sync request
+     */
+    @Param(0)
+    @NonNull UUID getSyncId();
+
+    /**
+     * Gets the sync type.
+     *
+     * @return the sync type
+     */
+    @Param(1)
+    @NonNull SyncType getType();
+
+    /**
+     * Gets if a sync occurred.
+     *
+     * <p>For {@link SyncType} = {@link SyncType#FULL FULL}, this method always returns true.</p>
+     *
+     * <p>For {@link SyncType} = {@link SyncType#SPECIFIC_USER SPECIFIC_USER}, this method returns true if the
+     * user in question was online/loaded in memory at the time, and false otherwise.</p>
+     *
+     * @return if a sync occurred
+     */
+    @Param(2)
+    boolean didSyncOccur();
+
+    /**
+     * Gets the unique id of the specific user that has been synced, if applicable.
+     *
+     * @return the unique id of the specific user
+     */
+    @Param(3)
+    @Nullable UUID getSpecificUserUniqueId();
+
+}
@@ -28,7 +28,10 @@ package net.luckperms.api.event.sync;
 import net.luckperms.api.event.LuckPermsEvent;

 /**
- * Called when an sync task has been completed
+ * Called after a full synchronisation task has been completed.
+ *
+ * <p>Note: this event is also called after synchronisations that were triggered over the network.
+ * In other words, this event will be called in addition to {@link PostNetworkSyncEvent}.</p>
 */
 public interface PostSyncEvent extends LuckPermsEvent {

@@ -28,13 +28,16 @@ package net.luckperms.api.event.sync;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.Cancellable;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;

 import java.util.UUID;

 /**
- * Called before a received network sync task runs
+ * Called after a request for synchronisation has been received via the messaging service,
+ * but before it has actually been completed.
+ *
+ * <p>Note: the generic {@link PreSyncEvent} will also be called for {@link SyncType#FULL full syncs}.</p>
 */
 public interface PreNetworkSyncEvent extends LuckPermsEvent, Cancellable {

@@ -46,4 +49,22 @@ public interface PreNetworkSyncEvent extends LuckPermsEvent, Cancellable {
    @Param(0)
    @NonNull UUID getSyncId();

+    /**
+     * Gets the sync type.
+     *
+     * @return the sync type
+     * @since 5.5
+     */
+    @Param(1)
+    @NonNull SyncType getType();
+
+    /**
+     * Gets the unique id of the specific user that will be synced, if applicable.
+     *
+     * @return the unique id of the specific user
+     * @since 5.5
+     */
+    @Param(2)
+    @Nullable UUID getSpecificUserUniqueId();
+
 }
@@ -29,7 +29,10 @@ import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.Cancellable;

 /**
- * Called before a sync task runs
+ * Called just before a full synchronisation task runs.
+ *
+ * <p>Note: this event is also called before synchronisations that were triggered over the network.
+ * In other words, this event will be called in addition to {@link PreNetworkSyncEvent}.</p>
 */
 public interface PreSyncEvent extends LuckPermsEvent, Cancellable {

@@ -23,20 +23,23 @@
 *  SOFTWARE.
 */

-package org.spongepowered.api.service.permission;
-
-import java.util.concurrent.CompletableFuture;
+package net.luckperms.api.event.sync;

 /**
- * This is included, as the interface didn't exist in API6.
- * We just shade it into the LP jar so we can still implement it. :)
+ * Represents the type of synchronisation task.
+ *
+ * @since 5.5
 */
-public interface SubjectReference {
+public enum SyncType {

-    String getCollectionIdentifier();
+    /**
+     * A full sync will be performed - all groups, users and tracks
+     */
+    FULL,

-    String getSubjectIdentifier();
+    /**
+     * Only a specific user will be synced
+     */
+    SPECIFIC_USER

-    CompletableFuture<Subject> resolve();
-
-}
+}
@@ -29,7 +29,6 @@ import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.cause.CreationCause;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.track.Track;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -28,7 +28,6 @@ package net.luckperms.api.event.track;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.cause.DeletionCause;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.List;
@@ -28,7 +28,6 @@ package net.luckperms.api.event.track;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.track.Track;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -26,7 +26,6 @@
 package net.luckperms.api.event.track.mutate;

 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -28,7 +28,6 @@ package net.luckperms.api.event.track.mutate;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.track.Track;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -26,7 +26,6 @@
 package net.luckperms.api.event.track.mutate;

 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -26,7 +26,6 @@
 package net.luckperms.api.event.type;

 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.concurrent.atomic.AtomicBoolean;
@@ -26,7 +26,6 @@
 package net.luckperms.api.event.type;

 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.concurrent.atomic.AtomicReference;
@@ -27,7 +27,6 @@ package net.luckperms.api.event.type;

 import net.luckperms.api.event.source.Source;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.cacheddata.CachedDataManager;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.user.User;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.cacheddata.CachedDataManager;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.user.User;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -27,7 +27,6 @@ package net.luckperms.api.event.user;

 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.UUID;
@@ -28,7 +28,6 @@ package net.luckperms.api.event.user;
 import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.user.User;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -29,7 +29,6 @@ import net.luckperms.api.event.LuckPermsEvent;
 import net.luckperms.api.event.type.Cancellable;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.user.User;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -30,7 +30,6 @@ import net.luckperms.api.event.type.Sourced;
 import net.luckperms.api.event.util.Param;
 import net.luckperms.api.model.user.User;
 import net.luckperms.api.track.Track;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.Optional;
@@ -26,12 +26,12 @@
 package net.luckperms.api.messaging;

 import net.luckperms.api.LuckPerms;
+import net.luckperms.api.event.messaging.CustomMessageReceiveEvent;
 import net.luckperms.api.model.user.User;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
- * A means to push changes to other servers using the platforms networking
+ * A means to send messages to other servers using the platforms networking
 */
 public interface MessagingService {

@@ -40,7 +40,7 @@ public interface MessagingService {
     *
     * @return the name of this messaging service
     */
-    String getName();
+    @NonNull String getName();

    /**
     * Uses the messaging service to inform other servers about a general
@@ -72,4 +72,44 @@ public interface MessagingService {
     */
    void pushUserUpdate(@NonNull User user);

+    /**
+     * Uses the messaging service to send a message with a custom payload.
+     *
+     * <p>The intended use case of this functionality is to allow plugins/mods
+     * to send <b>lightweight</b> and <b>permissions-related</b> custom messages
+     * between instances, piggy-backing on top of the messenger abstraction
+     * already built into LuckPerms.</p>
+     *
+     * <p>It is <b>not</b> intended as a full message broker replacement/abstraction.
+     * Note that some of the messenger implementations in LuckPerms cannot handle
+     * a high volume of messages being sent (for example the SQL messenger).
+     * Additionally, some implementations do not give any guarantees that a message
+     * will be delivered on time or even at all (for example the plugin message
+     * messengers).</p>
+     *
+     * <p>With all of that in mind, please consider that if you are using this
+     * functionality to send messages that have nothing to do with LuckPerms or
+     * permissions, or that require guarantees around delivery reliability, you
+     * are most likely misusing the API and would be better off building your own
+     * integration with a message broker.</p>
+     *
+     * <p>Whilst there is (currently) no strict validation, it is recommended
+     * that the channel id should use the same format as Minecraft resource locations /
+     * namespaced keys. For example, a plugin called "SuperRanks" sending rank-up
+     * notifications using custom payload messages might use the channel id
+     * {@code "superranks:notifications"} for this purpose.</p>
+     *
+     * <p>The payload can be any valid UTF-8 string.</p>
+     *
+     * <p>The message will be delivered asynchronously.</p>
+     *
+     * <p>Other LuckPerms instances that receive the message will publish it to API
+     * consumers using the {@link CustomMessageReceiveEvent}.</p>
+     *
+     * @param channelId the channel id
+     * @param payload the message payload
+     * @since 5.5
+     */
+    void sendCustomMessage(@NonNull String channelId, @NonNull String payload);
+
 }
@@ -27,7 +27,6 @@ package net.luckperms.api.messenger;

 import net.luckperms.api.messenger.message.Message;
 import net.luckperms.api.messenger.message.OutgoingMessage;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.ApiStatus.NonExtendable;

@@ -27,7 +27,6 @@ package net.luckperms.api.messenger;

 import net.luckperms.api.messenger.message.Message;
 import net.luckperms.api.messenger.message.OutgoingMessage;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.ApiStatus.OverrideOnly;

@@ -26,7 +26,6 @@
 package net.luckperms.api.messenger;

 import net.luckperms.api.LuckPerms;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.ApiStatus.OverrideOnly;

@@ -26,7 +26,6 @@
 package net.luckperms.api.messenger.message;

 import net.luckperms.api.messenger.Messenger;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.ApiStatus.NonExtendable;

@@ -26,7 +26,6 @@
 package net.luckperms.api.messenger.message;

 import net.luckperms.api.messenger.IncomingMessageConsumer;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -27,7 +27,6 @@ package net.luckperms.api.messenger.message.type;

 import net.luckperms.api.actionlog.Action;
 import net.luckperms.api.messenger.message.Message;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -0,0 +1,56 @@
+/*
+ * This file is part of LuckPerms, licensed under the MIT License.
+ *
+ *  Copyright (c) lucko (Luck) <luck@lucko.me>
+ *  Copyright (c) contributors
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in all
+ *  copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ *  SOFTWARE.
+ */
+
+package net.luckperms.api.messenger.message.type;
+
+import net.luckperms.api.messenger.message.Message;
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+/**
+ * Represents a "custom payload" message.
+ *
+ * <p>Used by API consumers to send custom messages between servers.</p>
+ *
+ * @see net.luckperms.api.messaging.MessagingService#sendCustomMessage(String, String)
+ * @see net.luckperms.api.event.messaging.CustomMessageReceiveEvent
+ * @since 5.5
+ */
+public interface CustomMessage extends Message {
+
+    /**
+     * Gets the channel identifier.
+     *
+     * @return the namespace
+     */
+    @NonNull String getChannelId();
+
+    /**
+     * Gets the payload.
+     *
+     * @return the payload
+     */
+    @NonNull String getPayload();
+
+}
@@ -26,7 +26,6 @@
 package net.luckperms.api.messenger.message.type;

 import net.luckperms.api.messenger.message.Message;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.UUID;
@@ -26,7 +26,6 @@
 package net.luckperms.api.metastacking;

 import net.luckperms.api.query.OptionKey;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -27,7 +27,6 @@ package net.luckperms.api.metastacking;

 import net.luckperms.api.node.ChatMetaType;
 import net.luckperms.api.node.types.ChatMetaNode;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;

@@ -35,7 +35,6 @@ import net.luckperms.api.node.Node;
 import net.luckperms.api.node.NodeType;
 import net.luckperms.api.query.Flag;
 import net.luckperms.api.query.QueryOptions;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -26,7 +26,6 @@
 package net.luckperms.api.model;

 import net.luckperms.api.model.user.UserManager;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.Unmodifiable;
@@ -29,7 +29,6 @@ import net.luckperms.api.model.PermissionHolder;
 import net.luckperms.api.node.Node;
 import net.luckperms.api.track.Track;
 import net.luckperms.api.util.Result;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -35,7 +35,6 @@ import net.luckperms.api.model.user.UserManager;
 import net.luckperms.api.node.Node;
 import net.luckperms.api.node.NodeEqualityPredicate;
 import net.luckperms.api.util.Tristate;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.Unmodifiable;

@@ -27,7 +27,6 @@ package net.luckperms.api.model.group;

 import net.luckperms.api.model.PermissionHolder;
 import net.luckperms.api.query.QueryOptions;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;

@@ -28,7 +28,6 @@ package net.luckperms.api.model.group;
 import net.luckperms.api.node.HeldNode;
 import net.luckperms.api.node.Node;
 import net.luckperms.api.node.matcher.NodeMatcher;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.Unmodifiable;
@@ -27,7 +27,6 @@ package net.luckperms.api.model.user;

 import net.luckperms.api.model.PermissionHolder;
 import net.luckperms.api.model.data.DataMutateResult;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;

@@ -29,7 +29,6 @@ import net.luckperms.api.model.PlayerSaveResult;
 import net.luckperms.api.node.HeldNode;
 import net.luckperms.api.node.Node;
 import net.luckperms.api.node.matcher.NodeMatcher;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.Unmodifiable;
@@ -28,9 +28,10 @@ package net.luckperms.api.node;
 import net.luckperms.api.node.types.ChatMetaNode;
 import net.luckperms.api.node.types.PrefixNode;
 import net.luckperms.api.node.types.SuffixNode;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

+import java.util.Locale;
+
 /**
 * Represents a type of chat meta
 */
@@ -70,7 +71,7 @@ public enum ChatMetaType {
    private final NodeType<? extends ChatMetaNode<?, ?>> nodeType;

    ChatMetaType(NodeType<? extends ChatMetaNode<?, ?>> nodeType) {
-        this.name = nodeType.name().toLowerCase();
+        this.name = nodeType.name().toLowerCase(Locale.ROOT);
        this.nodeType = nodeType;
    }

@@ -26,7 +26,6 @@
 package net.luckperms.api.node;

 import net.luckperms.api.model.PermissionHolder;
-
 import org.checkerframework.checker.nullness.qual.NonNull;

 /**
@@ -36,7 +36,6 @@ import net.luckperms.api.node.types.PrefixNode;
 import net.luckperms.api.node.types.RegexPermissionNode;
 import net.luckperms.api.node.types.SuffixNode;
 import net.luckperms.api.node.types.WeightNode;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.ApiStatus.NonExtendable;
@@ -201,11 +200,11 @@ public interface Node {
    /**
     * Gets the metadata corresponding to the given <code>key</code>, if present.
     *
-     * @param key the key
     * @param <T> the metadata type
+     * @param key the key
     * @return the data, if present
     */
-    <T> Optional<T> getMetadata(NodeMetadataKey<T> key);
+    <T> Optional<T> getMetadata(@NonNull NodeMetadataKey<T> key);

    /**
     * Gets the metadata corresponding to the given <code>key</code>, throwing an exception
@@ -216,7 +215,7 @@ public interface Node {
     * @return the data
     * @throws IllegalStateException if data isn't present
     */
-    default <T> T metadata(NodeMetadataKey<T> key) throws IllegalStateException {
+    default <T> T metadata(@NonNull NodeMetadataKey<T> key) throws IllegalStateException {
        return getMetadata(key).orElseThrow(() -> new IllegalStateException("Node '" + getKey() + "' does not have '" + key.name() + "' attached."));
    }

@@ -27,7 +27,6 @@ package net.luckperms.api.node;

 import net.luckperms.api.context.ContextSet;
 import net.luckperms.api.node.metadata.NodeMetadataKey;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 import org.jetbrains.annotations.ApiStatus.NonExtendable;
@@ -109,7 +108,7 @@ public interface NodeBuilder<N extends ScopedNode<N, B>, B extends NodeBuilder<N
     * @param unit     the unit <code>duration</code> is measured in
     * @return the builder
     */
-    default @NonNull B expiry(long duration, TimeUnit unit) {
+    default @NonNull B expiry(long duration, @NonNull TimeUnit unit) {
        if (duration <= 0) {
            throw new IllegalArgumentException("duration must be positive");
        }
@@ -33,7 +33,6 @@ import net.luckperms.api.node.types.PrefixNode;
 import net.luckperms.api.node.types.RegexPermissionNode;
 import net.luckperms.api.node.types.SuffixNode;
 import net.luckperms.api.node.types.WeightNode;
-
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.jetbrains.annotations.ApiStatus.Internal;

@@ -34,6 +34,7 @@ import net.luckperms.api.node.types.PrefixNode;
 import net.luckperms.api.node.types.RegexPermissionNode;
 import net.luckperms.api.node.types.SuffixNode;
 import net.luckperms.api.node.types.WeightNode;
+import org.checkerframework.checker.nullness.qual.NonNull;

 import java.util.Objects;
 import java.util.Optional;
@@ -48,59 +49,105 @@ public interface NodeType<T extends Node> {
    /**
     * Node type for {@link PermissionNode}.
     */
-    NodeType<PermissionNode> PERMISSION = new SimpleNodeType<>("PERMISSION", n ->  n instanceof PermissionNode, n -> (PermissionNode) n);
+    NodeType<PermissionNode> PERMISSION = new SimpleNodeType<>(
+            "PERMISSION",
+            n -> n instanceof PermissionNode,
+            n -> (PermissionNode) n
+    );

    /**
     * Node type for {@link RegexPermissionNode}.
     */
-    NodeType<RegexPermissionNode> REGEX_PERMISSION = new SimpleNodeType<>("REGEX_PERMISSION", n ->  n instanceof RegexPermissionNode, n -> (RegexPermissionNode) n);
+    NodeType<RegexPermissionNode> REGEX_PERMISSION = new SimpleNodeType<>(
+            "REGEX_PERMISSION",
+            n -> n instanceof RegexPermissionNode,
+            n -> (RegexPermissionNode) n
+    );

    /**
     * Node type for {@link InheritanceNode}.
     */
-    NodeType<InheritanceNode> INHERITANCE = new SimpleNodeType<>("INHERITANCE", n ->  n instanceof InheritanceNode, n -> (InheritanceNode) n);
+    NodeType<InheritanceNode> INHERITANCE = new SimpleNodeType<>(
+            "INHERITANCE",
+            n -> n instanceof InheritanceNode,
+            n -> (InheritanceNode) n
+    );

    /**
     * Node type for {@link PrefixNode}.
     */
-    NodeType<PrefixNode> PREFIX = new SimpleNodeType<>("PREFIX", n ->  n instanceof PrefixNode, n -> (PrefixNode) n);
+    NodeType<PrefixNode> PREFIX = new SimpleNodeType<>(
+            "PREFIX",
+            n -> n instanceof PrefixNode,
+            n -> (PrefixNode) n
+    );

    /**
     * Node type for {@link SuffixNode}.
     */
-    NodeType<SuffixNode> SUFFIX = new SimpleNodeType<>("SUFFIX", n ->  n instanceof SuffixNode, n -> (SuffixNode) n);
+    NodeType<SuffixNode> SUFFIX = new SimpleNodeType<>(
+            "SUFFIX",
+            n -> n instanceof SuffixNode,
+            n -> (SuffixNode) n
+    );

    /**
     * Node type for {@link MetaNode}.
     */
-    NodeType<MetaNode> META = new SimpleNodeType<>("META", n ->  n instanceof MetaNode, n -> (MetaNode) n);
+    NodeType<MetaNode> META = new SimpleNodeType<>(
+            "META",
+            n -> n instanceof MetaNode,
+            n -> (MetaNode) n
+    );

    /**
     * Node type for {@link WeightNode}.
     */
-    NodeType<WeightNode> WEIGHT = new SimpleNodeType<>("WEIGHT", n ->  n instanceof WeightNode, n -> (WeightNode) n);
+    NodeType<WeightNode> WEIGHT = new SimpleNodeType<>(
+            "WEIGHT",
+            n -> n instanceof WeightNode,
+            n -> (WeightNode) n
+    );

    /**
     * Node type for {@link DisplayNameNode}.
     */
-    NodeType<DisplayNameNode> DISPLAY_NAME = new SimpleNodeType<>("DISPLAY_NAME", n ->  n instanceof DisplayNameNode, n -> (DisplayNameNode) n);
+    NodeType<DisplayNameNode> DISPLAY_NAME = new SimpleNodeType<>(
+            "DISPLAY_NAME",
+            n -> n instanceof DisplayNameNode,
+            n -> (DisplayNameNode) n
+    );

    /**
     * Node type for {@link ChatMetaNode}.
+     *
+     * <p>This is an abstract type, and therefore will never
+     * be returned from {@link Node#getType()}.</p>
     */
-    NodeType<ChatMetaNode<?, ?>> CHAT_META = new SimpleNodeType<>("CHAT_META", n ->  n instanceof ChatMetaNode<?, ?>, n -> (ChatMetaNode<?, ?>) n);
+    NodeType<ChatMetaNode<?, ?>> CHAT_META = new SimpleNodeType<>(
+            "CHAT_META",
+            n -> n instanceof ChatMetaNode<?, ?>,
+            n -> (ChatMetaNode<?, ?>) n
+    );

    /**
     * Node type for {@link ChatMetaNode} or {@link MetaNode}.
+     *
+     * <p>This is an abstract type, and therefore will never
+     * be returned from {@link Node#getType()}.</p>
     */
-    NodeType<Node> META_OR_CHAT_META = new SimpleNodeType<>("META_OR_CHAT_META", n ->  META.matches(n) || CHAT_META.matches(n), Function.identity());
+    NodeType<Node> META_OR_CHAT_META = new SimpleNodeType<>(
+            "META_OR_CHAT_META",
+            n -> META.matches(n) || CHAT_META.matches(n),
+            Function.identity()
+    );

    /**
     * Gets a name for the node type.
     *
     * @return a name
     */
-    String name();
+    @NonNull String name();

    /**
     * Returns if the passed node matches the type
@@ -108,7 +155,7 @@ public interface NodeType<T extends Node> {
     * @param node the node to test
     * @return true if the node has the same type
     */
-    boolean matches(Node node);
+    boolean matches(@NonNull Node node);

    /**
     * Casts the given {@link Node} to the type defined by the {@link NodeType}.
@@ -120,7 +167,7 @@ public interface NodeType<T extends Node> {
     * @return the casted node
     * @throws IllegalArgumentException if the node to cast does not match the type
     */
-    T cast(Node node);
+    @NonNull T cast(@NonNull Node node);

    /**
     * Attempts to cast the given {@link Node} to the type defined by the
@@ -132,7 +179,7 @@ public interface NodeType<T extends Node> {
     * @param node the node to cast
     * @return an optional, possibly containing a casted node
     */
-    default Optional<T> tryCast(Node node) {
+    default @NonNull Optional<T> tryCast(@NonNull Node node) {
        Objects.requireNonNull(node, "node");
        if (!matches(node)) {
            return Optional.empty();
@@ -147,7 +194,7 @@ public interface NodeType<T extends Node> {
     *
     * @return a predicate for the {@link #matches(Node)} method.
     */
-    default Predicate<Node> predicate() {
+    default @NonNull Predicate<Node> predicate() {
        return this::matches;
    }

@@ -159,7 +206,7 @@ public interface NodeType<T extends Node> {
     * @param and a predicate to AND with the result of the type match check
     * @return a matching predicate, ANDed with the given predicate parameter
     */
-    default Predicate<Node> predicate(Predicate<? super T> and) {
+    default @NonNull Predicate<Node> predicate(@NonNull Predicate<? super T> and) {
        return node -> matches(node) && and.test(cast(node));
    }