fix(database): load SQL libraries with Quark

build.gradle.kts

@@ -66,19 +66,27 @@ dependencies {
     implementation(libs.xseries)
     implementation(libs.adventure.platform.bukkit)
     implementation(libs.triumph.gui)
-    implementation(libs.hikaricp)
-    implementation(libs.jdbi.core)
-    implementation(libs.jdbi.sqlobject)
-    implementation(libs.mariadb.client)
     implementation(libs.quark.bukkit)
 
     /*
-     * Kotlin is compiled against locally, but downloaded and loaded at runtime
-     * by Quark to reduce the SpigotMC upload jar size.
+     * Large runtime libraries are compiled against locally, but downloaded and loaded
+     * by Quark to keep the file size slim.
      */
     compileOnly(libs.kotlin.stdlib)
     quark(libs.kotlin.stdlib)
 
+    compileOnly(libs.hikaricp)
+    quark(libs.hikaricp)
+
+    compileOnly(libs.jdbi.core)
+    quark(libs.jdbi.core)
+
+    compileOnly(libs.jdbi.sqlobject)
+    quark(libs.jdbi.sqlobject)
+
+    compileOnly(libs.mariadb.client)
+    quark(libs.mariadb.client)
+
     /*
      * Provided by the server or by other plugins at runtime.
      * These must not be bundled or relocated.
@@ -284,20 +292,7 @@ tasks.named<ShadowJar>("shadowJar") {
     }
 
     /*
-     * Database stack
-     */
-    relocate("com.zaxxer.hikari", "$relocationRoot.hikari") {
-        skipStringConstants = true
-    }
-    relocate("org.jdbi", "$relocationRoot.jdbi") {
-        skipStringConstants = true
-    }
-    relocate("org.mariadb.jdbc", "$relocationRoot.mariadb") {
-        skipStringConstants = true
-    }
-
-    /*
-     * Common transitive libraries pulled by the database/config stack.
+     * Common transitive libraries pulled by shaded dependencies.
      * These are intentionally narrow to avoid relocating server/plugin APIs.
      */
     relocate("org.antlr", "$relocationRoot.antlr") {
@@ -376,10 +371,8 @@ fun RunServer.configureGuildsRunServer(target: MinecraftRunTarget) {
     downloadPlugins {
         /*
          * EssentialsX:
-         * Hangar marks this release as an external download, so run-task's
-         * Hangar downloader returns 404. Use GitHub Releases instead.
          */
-        url("https://ci.ender.zone/job/EssentialsX/lastSuccessfulBuild/artifact/jars/EssentialsX-2.22.0-dev+112-5baf239.jar")
+        github("EssentialsX", "Essentials", "2.22.0", "EssentialsX-2.22.0.jar")
 
         /*
          * LuckPerms:

src/main/java/me/glaremasters/guilds/database/DatabaseManager.java

@@ -59,7 +59,7 @@ public DatabaseManager(SettingsManager settingsManager, DatabaseBackend backend)
         switch (backend) {
             case MYSQL:
                 config.setPoolName("Guilds MySQL Connection Pool");
-                config.setDataSourceClassName(requireDataSourceName(
+                config.setDataSourceClassName(requireDataSourceClassName(
                         backend,
                         "com.mysql.cj.jdbc.MysqlDataSource",
                         "com.mysql.jdbc.jdbc2.optional.MysqlDataSource"
@@ -77,11 +77,12 @@ public DatabaseManager(SettingsManager settingsManager, DatabaseBackend backend)
                 break;
             case SQLITE:
                 config.setPoolName("Guilds SQLite Connection Pool");
+                config.setDriverClassName(requireDriverClassName(backend, "org.sqlite.JDBC"));
                 config.setJdbcUrl("jdbc:sqlite:plugins/Guilds/guilds.db");
                 break;
             case MARIADB:
                 config.setPoolName("Guilds MariaDB Connection Pool");
-                config.setDataSourceClassName(requireDataSourceName(
+                config.setDataSourceClassName(requireDataSourceClassName(
                         backend,
                         "org.mariadb.jdbc.MariaDbDataSource"
                 ));
@@ -130,22 +131,41 @@ public HikariDataSource getHikari() {
         return hikari;
     }
 
-    private static String requireDataSourceName(DatabaseBackend backend, String... classNames) throws IOException {
+    private static String requireDataSourceClassName(DatabaseBackend backend, String... classNames) throws IOException {
+        return requireClassName("datasource", backend, classNames);
+    }
+
+    private static String requireDriverClassName(DatabaseBackend backend, String... classNames) throws IOException {
+        return requireClassName("driver", backend, classNames);
+    }
+
+    private static String requireClassName(String classType, DatabaseBackend backend, String... classNames) throws IOException {
         for (String className : classNames) {
             if (isClassAvailable(className)) {
                 return className;
             }
         }
 
         throw new IOException(
-                "No datasource class is available for the " + backend.getBackendName() +
-                        " backend. Tried: " + Arrays.toString(classNames)
+                "No " + classType + " class is available for the " + backend.getBackendName() +
+                        " backend. Tried: " + Arrays.toString(classNames) +
+                        ". Ensure the selected backend's JDBC driver is available to the server/plugin runtime."
         );
     }
 
     private static boolean isClassAvailable(String className) {
+        return isClassAvailable(className, DatabaseManager.class.getClassLoader()) ||
+                isClassAvailable(className, Thread.currentThread().getContextClassLoader()) ||
+                isClassAvailable(className, ClassLoader.getSystemClassLoader());
+    }
+
+    private static boolean isClassAvailable(String className, ClassLoader classLoader) {
+        if (classLoader == null) {
+            return false;
+        }
+
         try {
-            Class.forName(className);
+            Class.forName(className, false, classLoader);
             return true;
         } catch (ClassNotFoundException ignored) {
             return false;
@@ -158,7 +178,8 @@ private static String getConnectionDetails(
             HikariConfig config
     ) {
         if (backend == DatabaseBackend.SQLITE) {
-            return "jdbcUrl=" + config.getJdbcUrl();
+            return "jdbcUrl=" + config.getJdbcUrl() +
+                    ", driver=" + config.getDriverClassName();
         }
 
         return "host=" + settingsManager.getProperty(StorageSettings.SQL_HOST) +