Implement Velocity metrics collection and plugin factory

Author: NonSwag

settings.gradle.kts

@@ -3,5 +3,6 @@ plugins {
 }
 
 rootProject.name = "dev-kits"
+include("bukkit")
 include("core")
-include("bukkit")
+include("velocity")

velocity/build.gradle.kts

@@ -0,0 +1,8 @@
+repositories {
+    maven("https://repo.papermc.io/repository/maven-public/")
+}
+
+dependencies {
+    api(project(":core"))
+    compileOnly("com.velocitypowered:velocity-api:3.4.0-SNAPSHOT")
+}

velocity/src/main/java/dev/faststats/velocity/VelocityMetrics.java

@@ -0,0 +1,32 @@
+package dev.faststats.velocity;
+
+import com.google.inject.Inject;
+import com.velocitypowered.api.plugin.annotation.DataDirectory;
+import com.velocitypowered.api.proxy.ProxyServer;
+import dev.faststats.core.Metrics;
+import org.slf4j.Logger;
+
+import java.nio.file.Path;
+
+/**
+ * Bukkit metrics implementation.
+ *
+ * @since 0.1.0
+ */
+public sealed interface VelocityMetrics extends Metrics permits VelocityMetricsImpl {
+    final class Factory extends VelocityMetricsImpl.Factory {
+        /**
+         * Creates a new metrics factory for Velocity.
+         *
+         * @param server        the velocity server
+         * @param logger        the logger
+         * @param dataDirectory the data directory
+         * @apiNote This instance is automatically injected into your plugin.
+         * @since 0.1.0
+         */
+        @Inject
+        private Factory(ProxyServer server, Logger logger, @DataDirectory Path dataDirectory) {
+            super(server, logger, dataDirectory);
+        }
+    }
+}

velocity/src/main/java/dev/faststats/velocity/VelocityMetricsImpl.java

@@ -0,0 +1,106 @@
+package dev.faststats.velocity;
+
+import com.google.gson.JsonObject;
+import com.velocitypowered.api.plugin.PluginContainer;
+import com.velocitypowered.api.plugin.annotation.DataDirectory;
+import com.velocitypowered.api.proxy.ProxyServer;
+import dev.faststats.core.Metrics;
+import dev.faststats.core.SimpleMetrics;
+import org.jetbrains.annotations.Async;
+import org.jspecify.annotations.Nullable;
+import org.slf4j.Logger;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.util.Optional;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Supplier;
+
+final class VelocityMetricsImpl extends SimpleMetrics implements VelocityMetrics {
+    private final Logger logger;
+    private final ProxyServer server;
+    private final PluginContainer plugin;
+
+    private VelocityMetricsImpl(
+            SimpleMetrics.Factory<?> factory,
+            Logger logger,
+            ProxyServer server,
+            Path config,
+            PluginContainer plugin
+    ) throws IOException, IllegalStateException {
+        super(factory, config);
+
+        this.logger = logger;
+        this.server = server;
+        this.plugin = plugin;
+
+        startSubmitting();
+    }
+
+    @Async.Schedule
+    private void startSubmitting() {
+        startSubmitting(0, 30, TimeUnit.MINUTES);
+    }
+
+    @Override
+    protected void appendDefaultData(JsonObject charts) {
+        var pluginVersion = plugin.getDescription().getVersion().orElse("unknown");
+        var size = server.getPlayerCount();
+
+        charts.addProperty("online_mode", server.getConfiguration().isOnlineMode());
+        charts.addProperty("plugin_version", pluginVersion);
+        charts.addProperty("server_type", server.getVersion().getName());
+        charts.addProperty("proxy_version", server.getVersion().getVersion());
+        charts.addProperty("proxy_vendor", server.getVersion().getVendor());
+        if (size != 0) charts.addProperty("player_count", size);
+    }
+
+    @Override
+    protected void error(String message, @Nullable Throwable throwable) {
+        if (!isDebug()) return;
+        var msg = "[" + VelocityMetricsImpl.class.getName() + "]: " + message;
+        logger.error(msg, throwable);
+    }
+
+    @Override
+    protected void warn(String message) {
+        if (!isDebug()) return;
+        var msg = "[" + VelocityMetricsImpl.class.getName() + "]: " + message;
+        logger.warn(msg);
+    }
+
+    @Override
+    protected void info(String message) {
+        if (!isDebug()) return;
+        var msg = "[" + VelocityMetricsImpl.class.getName() + "]: " + message;
+        logger.info(msg);
+    }
+
+    private <T> Optional<T> tryOrEmpty(Supplier<@Nullable T> supplier) {
+        try {
+            return Optional.ofNullable(supplier.get());
+        } catch (NoSuchMethodError | Exception e) {
+            error("Failed to call supplier", e);
+            return Optional.empty();
+        }
+    }
+
+    static class Factory extends SimpleMetrics.Factory<Object> {
+        protected final Logger logger;
+        protected final Path dataDirectory;
+        protected final ProxyServer server;
+
+        public Factory(ProxyServer server, Logger logger, @DataDirectory Path dataDirectory) {
+            this.logger = logger;
+            this.dataDirectory = dataDirectory;
+            this.server = server;
+        }
+
+        @Override
+        public Metrics create(Object plugin) throws IOException, IllegalStateException, IllegalArgumentException {
+            var faststats = dataDirectory.resolveSibling("faststats");
+            var container = server.getPluginManager().ensurePluginContainer(plugin);
+            return new VelocityMetricsImpl(this, logger, server, faststats.resolve("config.json"), container);
+        }
+    }
+}

velocity/src/main/java/module-info.java

@@ -0,0 +1,15 @@
+import org.jspecify.annotations.NullMarked;
+
+@NullMarked
+module dev.faststats.velocity {
+    exports dev.faststats.velocity;
+
+    requires com.google.gson;
+    requires com.google.guice;
+    requires com.velocitypowered.api;
+    requires dev.faststats.core;
+    requires org.slf4j;
+
+    requires static org.jetbrains.annotations;
+    requires static org.jspecify;
+}