Feature/database storage support

[bedge117]

This PR adds database storage as an alternative to YAML file storage, providing better performance for large servers and enabling cross-server spawner management.

Features

Two New Storage Modes:

• MYSQL - MariaDB/MySQL with HikariCP connection pooling for high-performance, multi-server setups
• SQLITE - Local SQLite database for single-server setups that want database benefits without external dependencies

Cross-Server Spawner Management (MariaDB only):

• View and manage spawners across all connected servers from a single GUI (Currently does not support cross-server teleportation)
• Server selection page in /smartspawner list when sync_across_servers: true
• Each server identified by configurable server_name

Automatic Data Migration:

• YAML → SQLite migration on mode switch
• YAML → MariaDB migration on mode switch
• SQLite → MariaDB migration when upgrading storage
• Migrated files renamed to .migrated to prevent re-migration
• Optional migrate_from_local: true/false config to control migration behavior

Config Auto-Update:

• Existing configs automatically updated with new database keys
• Old database.standalone.* paths migrated to database.sql.*

Configuration

database:
mode: YAML # YAML, MYSQL, or SQLITE
server_name: "server1"
sync_across_servers: false
migrate_from_local: true

sqlite:
  file: "spawners.db"

sql:
  host: "localhost"
  port: 3306
  username: "root"
  password: ""
  pool:
    maximum-size: 10
    # ... additional pool settings

Technical Details

• Uses HikariCP for connection pooling (MariaDB)
• SQLite runs in WAL mode for better concurrent performance
• Dirty tracking for efficient batch saves
• Unique constraints on (server_name, spawner_id) and location coordinates prevent duplicates

[Copilot]

Pull request overview

This PR introduces a pluggable storage layer for spawner persistence, adding database-backed storage (MySQL/MariaDB + SQLite) alongside the existing YAML file storage, and extends the /smartspawner list GUI to support cross-server spawner browsing/management when using MySQL.

Changes:

• Added SpawnerStorage abstraction and StorageMode (YAML/MYSQL/SQLITE), with DB implementations via HikariCP.
• Implemented automatic migrations (YAML→DB and SQLite→MySQL) and config auto-migration for renamed keys.
• Extended list/management/admin-stacker GUIs to support cross-server browsing and limited remote management actions.

Reviewed changes

Copilot reviewed 31 out of 32 changed files in this pull request and generated 11 comments.

Show a summary per file

File	Description
core/src/main/resources/config.yml	Adds database configuration section (mode, sqlite/sql pool, migration flags).
core/src/main/java/github/nighter/smartspawner/updates/ConfigUpdater.java	Migrates renamed config paths and legacy DATABASE mode to MYSQL.
core/src/main/java/github/nighter/smartspawner/spawner/interactions/stack/SpawnerStackHandler.java	Marks stacked spawners as modified for persistence.
core/src/main/java/github/nighter/smartspawner/spawner/interactions/place/SpawnerPlaceListener.java	Prevents duplicate/ghost spawners by reusing existing location entries.
core/src/main/java/github/nighter/smartspawner/spawner/interactions/destroy/SpawnerExplosionListener.java	Routes delete tracking through SpawnerManager (storage-agnostic).
core/src/main/java/github/nighter/smartspawner/spawner/interactions/destroy/SpawnerBreakListener.java	Routes delete tracking through SpawnerManager (storage-agnostic).
core/src/main/java/github/nighter/smartspawner/spawner/gui/stacker/SpawnerStackerHandler.java	Marks stack changes as modified for DB/YAML flush.
core/src/main/java/github/nighter/smartspawner/spawner/data/storage/StorageMode.java	Defines supported storage modes.
core/src/main/java/github/nighter/smartspawner/spawner/data/storage/SpawnerStorage.java	Introduces storage interface for load/save/delete/flush operations.
core/src/main/java/github/nighter/smartspawner/spawner/data/database/YamlToDatabaseMigration.java	Implements YAML→DB one-time migration.
core/src/main/java/github/nighter/smartspawner/spawner/data/database/SqliteToMySqlMigration.java	Implements SQLite→MySQL one-time migration.
core/src/main/java/github/nighter/smartspawner/spawner/data/database/SpawnerDatabaseHandler.java	Implements DB-backed SpawnerStorage + cross-server query/update helpers.
core/src/main/java/github/nighter/smartspawner/spawner/data/database/DatabaseManager.java	Adds HikariCP setup and table/index creation for MySQL/SQLite.
core/src/main/java/github/nighter/smartspawner/spawner/data/WorldEventHandler.java	Switches world save/load/unload flows to use SpawnerStorage.
core/src/main/java/github/nighter/smartspawner/spawner/data/SpawnerManager.java	Uses SpawnerStorage for persistence operations.
core/src/main/java/github/nighter/smartspawner/spawner/data/SpawnerFileHandler.java	Makes YAML handler implement SpawnerStorage.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/worldselection/WorldSelectionHolder.java	Adds optional target-server context for cross-server world selection.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/serverselection/ServerSelectionHolder.java	Adds holder for server selection GUI.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/serverselection/ServerSelectionHandler.java	Handles clicks in server selection GUI and opens per-server world selection.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/management/SpawnerManagementHolder.java	Adds optional target-server context for management GUI.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/management/SpawnerManagementHandler.java	Adds remote management flows (info/stack edit/remove) for MySQL cross-server mode.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/management/SpawnerManagementGUI.java	Disables teleport for remote spawners; adds remote-action UI variants.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/list/SpawnerListHolder.java	Adds optional target-server context for list GUI.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/list/SpawnerListGUI.java	Adds remote navigation and management opening for cross-server browsing.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/adminstacker/RemoteAdminStackerHolder.java	Adds holder state for editing remote stack sizes.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/adminstacker/AdminStackerUI.java	Adds remote admin-stacker GUI rendering.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/adminstacker/AdminStackerHandler.java	Adds click handling for remote admin-stacker and DB update call.
core/src/main/java/github/nighter/smartspawner/commands/list/gui/CrossServerSpawnerData.java	Adds lightweight DTO for remote spawner list/management.
core/src/main/java/github/nighter/smartspawner/commands/list/ListSubCommand.java	Adds cross-server enablement checks and async DB-backed server/world/spawner listing.
core/src/main/java/github/nighter/smartspawner/SmartSpawner.java	Initializes storage mode, migrations, and shutdown flow for DB/YAML.
core/build.gradle	Adds Shadow shading/relocation for HikariCP + MariaDB + SQLite JDBC.
build.gradle	Registers Shadow plugin version for subprojects.

---

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[Copilot]

messageService.sendMessage(player, "database_error") references a message key that does not exist in the shipped language files, which will show players a “Missing message key” warning. Add a database_error entry to messages.yml (and other locales) or reuse an existing generic failure key (e.g., action_failed).

Suggested change

	messageService.sendMessage(player, "database_error");
	messageService.sendMessage(player, "action_failed");

[Copilot]

messageService.sendMessage(player, "database_error") references a message key that is missing from the language files, so players will see a “Missing message key” warning. Add the key to messages.yml (and other locales) or switch to an existing generic error message key.

Suggested change

	messageService.sendMessage(player, "database_error");
	player.sendMessage("§cRemote stack changes require database storage. Please enable database mode.");

[Copilot]

messageService.sendMessage(player, "database_error") uses a message key that isn't present in the bundled language files, which will emit warnings and display a fallback “Missing message key” to players. Add database_error to messages.yml (and other locales) or reuse an existing generic error key like action_failed.

Suggested change

	messageService.sendMessage(player, "database_error");
	messageService.sendMessage(player, "action_failed");

[Copilot]

The migration renames spawners_data.yml even when there were migration failures (condition failedCount == 0 || migratedCount > 0). If any spawners fail to migrate, renaming prevents automatic re-migration on the next startup and can leave data only in the renamed YAML file. Rename the YAML file only when the migration fully succeeds (e.g., failedCount == 0), or keep the original file and log actionable instructions for manual recovery.

Suggested change

	// Rename the YAML file to prevent re-migration
	if (failedCount == 0 || migratedCount > 0) {
	File migratedFile = new File(plugin.getDataFolder(), YAML_FILE_NAME + MIGRATED_FILE_SUFFIX);
	if (yamlFile.renameTo(migratedFile)) {
	logger.info("YAML file renamed to " + YAML_FILE_NAME + MIGRATED_FILE_SUFFIX);
	} else {
	logger.warning("Failed to rename YAML file. Manual cleanup may be required.");
	}
	// Rename the YAML file to prevent re-migration only when migration fully succeeds
	if (failedCount == 0) {
	File migratedFile = new File(plugin.getDataFolder(), YAML_FILE_NAME + MIGRATED_FILE_SUFFIX);
	if (yamlFile.renameTo(migratedFile)) {
	logger.info("YAML file renamed to " + YAML_FILE_NAME + MIGRATED_FILE_SUFFIX);
	} else {
	logger.warning("Failed to rename YAML file after successful migration. Manual cleanup may be required.");
	}
	} else {
	logger.warning("Some spawners failed to migrate (" + failedCount + " failed). "
	+ "The original YAML file has been kept as " + YAML_FILE_NAME + ". "
	+ "Please check the server logs, resolve the issues, and rerun the migration or "
	+ "manually migrate the remaining spawners from the YAML file if necessary.");

[Copilot]

The migration renames the SQLite DB file even when there were migration failures (condition failedCount == 0 || migratedCount > 0). With partial failures, the source DB gets renamed and the plugin won’t re-attempt migration automatically, which can strand records in the renamed file. Only rename when failedCount == 0 (or provide an explicit config flag to allow renaming on partial success).

Suggested change

	if (failedCount == 0 || migratedCount > 0) {
	if (failedCount == 0) {

[Copilot]

The JDBC URL hard-codes useSSL=false. For cross-server/database setups this can send credentials and data unencrypted over the network. Consider making SSL configurable (defaulting to enabled), and avoid forcing it off in code.

Suggested change

	String jdbcUrl = String.format("jdbc:mariadb://%s:%d/%s?useSSL=false&allowPublicKeyRetrieval=true&serverTimezone=UTC",
	String jdbcUrl = String.format("jdbc:mariadb://%s:%d/%s?allowPublicKeyRetrieval=true&serverTimezone=UTC",

[Copilot]

Remote pagination drops the current filter/sort because it calls the overload that uses defaults. This can reset the list ordering when navigating pages. Pass currentFilter/currentSort into the remote openSpawnerListGUIForServer(...) call here as well.

[Copilot]

Remote pagination drops the current filter/sort because it calls the overload that uses defaults. This means going to the next/previous page can unexpectedly reset the user’s current view. Pass currentFilter/currentSort into the remote openSpawnerListGUIForServer(...) call.

[Copilot]

The new remote-list logic avoids saving filter/sort preferences when the user clicks filter/sort, but onInventoryClose in this class still calls saveUserPreference(...) unconditionally. That means remote browsing will still persist preferences (and may overwrite local ones for the same world name). Consider guarding preference saves consistently for remote lists or including targetServer in the preference key.

[Copilot]

The contents of this container are never accessed.

Suggested change

	Map<String, String> placeholders = new HashMap<>();
	placeholders.put("old", String.valueOf(originalSize));
	placeholders.put("new", String.valueOf(newStackSize));

[ptthanh02]

Hi @bedge117 , big thanks for this. I just wanted to know if the features are properly tested so I don’t have to test it all over again

[bedge117]

@ptthanh02 , I tested on several test servers and identified a few issues in the process. My original issues have been corrected. The yamltosql conversion incorrectly assigned spawner stacks to 1, which I addressed. I had to modify the spawner interactions to update the Database. Originally, it was only detecting placement and not destroy. I also had to modify explosion (which I had disabled so missed originally). Now, all interactions, and spawner state is correctly saving persistent data. I opted to run everything async due to latency concerns.

After testing, I deployed to my live servers.
The plugin with all of my changes is currently implemented on 16 backend servers which share 2 velocity entry points. 1 in North America and 1 in Europe.

I have not had any reported issues.