Libby (AlessioDP)

Changes in this fork

2.0.0 Beta

A beta version of the 2.0.0 update is available on the gradle branch, with many changes and improvements. Try it out!

Libby

A runtime dependency management library for plugins running in Java-based Minecraft server platforms.

Libraries can be downloaded from Maven repositories (or direct URLs) into a plugin's data folder, relocated and then loaded into the plugin's classpath at runtime.

Why use runtime dependency management?

Due to file size constraints on plugin hosting services like SpigotMC, some plugins with bundled dependencies become too large to be uploaded.

Using runtime dependency management, dependencies are downloaded and cached by the server and don't need to be bundled with the plugin, which significantly reduces the size of the plugin jar.

A smaller plugin jar also means shorter download times and less network strain for authors who self-host their plugins on servers with limited bandwidth.

Usage

Firstly, add the maven artifact to your pom.xml

<!-- Libby (AlessioDP) Repository -->
<repository>
  <id>AlessioDP</id>
  <url>https://repo.alessiodp.com/releases/</url>
</repository>

<dependency>
    <groupId>net.byteflux</groupId>
    <artifactId>libby-bukkit</artifactId> <!-- Replace bukkit if you're using another platform -->
    <version>1.3.1</version>
</dependency>

Remember to always relocate Libby to avoid conflicts

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <configuration>
        <relocations>
            <relocation>
                <pattern>net.byteflux.libby</pattern>
                <shadedPattern>yourPackage.libs.net.byteflux.libby</shadedPattern>
            </relocation>
        </relocations>
    </configuration>
</plugin>

Then, create a new LibraryManager instance

// Create a library manager for a Bukkit/Spigot plugin
BukkitLibraryManager bukkitLibraryManager = new BukkitLibraryManager(plugin);

// Create a library manager for a Bungee plugin
BungeeLibraryManager bungeeLibraryManager = new BungeeLibraryManager(plugin);

// Also Nukkit, Sponge, and Velocity are supported

Create a Library instance with the library builder

Library lib = Library.builder()
    .groupId("your{}dependency{}groupId") // "{}" is replaced with ".", useful to avoid unwanted changes made by maven-shade-plugin
    .artifactId("artifactId")
    .version("version")
     // The following are optional

     // Sets an id for the library
    .id("my-lib")
     // Relocation is applied to the downloaded jar before loading it
    .relocate("package{}to{}relocate", "the{}relocated{}package") // "{}" is replaced with ".", useful to avoid unwanted changes made by maven-shade-plugin
     // The library is loaded into an IsolatedClassLoader, which is in common between every library with the same id
    .isolatedLoad(true)
    .classifier("customClassifier")
    .checksum("Base64-encoded SHA-256 checksum")
    .build();

Finally, add Maven Central (or other repositories) to the library manager and download your library. To do this, you can use the LibraryManager#loadLibrary(Library libraryToLoad) method, which automatically downloads and then loads the provided library.

libraryManager.addMavenCentral();
libraryManager.loadLibrary(lib);

Complete code

BukkitLibraryManager libraryManager = new BukkitLibraryManager(plugin);

Library lib = Library.builder()
    .groupId("your{}dependency{}groupId") // "{}" is replaced with ".", useful to avoid unwanted changes made by maven-shade-plugin
    .artifactId("artifactId")
    .version("version")
     // The following are optional

     // Sets an id for the library
    .id("my-lib")
     // Relocation is applied to the downloaded jar before loading it
    .relocate("package{}to{}relocate", "the{}relocated{}package") // "{}" is replaced with ".", useful to avoid unwanted changes made by maven-shade-plugin
     // The library is loaded into an IsolatedClassLoader, which is in common between every library with the same id
    .isolatedLoad(true)
    .classifier("customClassifier")
    .checksum("Base64-encoded SHA-256 checksum")
    .build();

libraryManager.addMavenCentral();
libraryManager.loadLibrary(lib);

Credits

Special thanks to:

Luck for LuckPerms and its dependency management system which was the original inspiration for this project and another thanks for jar-relocator which is used by Libby to perform jar relocations.
Glare for convincing me (Byteflux) that I should publish this library instead of letting it sit around collecting dust :)