[Feat] Database Storage Backend with Smart Migration

[derrickmehaffy]

Summary

Add MariaDB/MySQL and PostgreSQL storage backends as alternatives to the current JSON file storage, targeting larger servers where file I/O becomes a bottleneck. Include a storage abstraction layer and a smart migration system for converting data between backends.

Features

Storage Abstraction Layer

• Common StorageProvider interface used by all managers
• Implementations: JsonStorageProvider (current), MySQLStorageProvider, PostgreSQLStorageProvider
• All managers interact through the abstraction — no direct file I/O

Database Backends

• MariaDB/MySQL support
• PostgreSQL support
• Connection pooling via HikariCP
• Prepared statements for all queries
• Proper schema with indexes for common lookups (player UUID, faction ID, chunk coordinates)

Configuration

{
  "storage": {
    "type": "json",
    "database": {
      "host": "localhost",
      "port": 3306,
      "database": "hyperfactions",
      "username": "root",
      "password": "",
      "pool-size": 10
    }
  }
}

Smart Migration

• /f admin migrate <from> <to> — Migrate data between backends (e.g., json mysql)
• Pre-migration backup (automatic)
• Progress reporting during migration
• Validation after migration (record count comparison)
• Rollback capability if migration fails

What Gets Migrated

• Faction data (all fields)
• Player data (memberships, power, profiles)
• Claim data (territory ownership)
• Relations (ally/enemy/neutral)
• Economy data (balances, transaction history)
• Zone data (safezones, warzones)
• Backup metadata

Design Principles

• JSON remains the default — zero-config for small servers
• Database backends are optional — no required dependencies
• HikariCP and database drivers loaded only when configured
• All operations remain async (CompletableFuture)

Origin

New feature for large server scalability. Not from original roadmap.