Sentinel

Sentinel is a Velocity plugin that securely links Minecraft accounts to Discord accounts. It integrates with a Discord bot to verify players before allowing login, helping to prevent impersonation and aiding in connecting players together. Sentinel also provides quarantine functionality to temporarily restrict access for problematic players.

Commands

Discord Commands

/link <code>
Link your Minecraft account to your Discord account.

/whois [discord: @user | minecraft: username]
Look up linked account info.

/quarantine

Purpose: Add a quarantine to a Discord user or show their current quarantine status.

Usage:

• Show status: /quarantine @user
• Add permanent quarantine: /quarantine @user reason:"Rule violation"
• Add temporary quarantine: /quarantine @user duration:2h reason:"Griefing"

Parameters:

• user (required): Discord user to quarantine
• duration (optional): Duration in format like 30m, 2h, 3d, 1w
• reason (optional): Reason for the quarantine

Duration formats:

• 30s = 30 seconds
• 15m = 15 minutes
• 2h = 2 hours
• 7d = 7 days
• 2w = 2 weeks

Features:

• Automatically kicks online players when quarantined
• Shows detailed status with colored Discord formatting
• Tracks creation time and administrator who created it
• Automatic cleanup of expired quarantines

/unquarantine

Purpose: Remove a quarantine from a Discord user.

Usage:

• /unquarantine @user

Parameters:

• user (required): Discord user to remove quarantine from

Features:

• Shows previous quarantine details when removing
• Only works if user is currently quarantined

Features

• Account Linking: Secure verification system linking Minecraft accounts to Discord
• Login Protection: Prevents unlinked accounts from joining (with configurable bypass servers)
• Role Management: Automatic Discord role assignment for linked players
• Quarantine System: Staff can quarantine problematic players with timed bans, preventing login and kicking online players
• Automatic Cleanup: Removes database entries for users who leave Discord
• Rate Limiting: Respects Discord API limits with intelligent rate limiting

Requirements

• Java 17+
• Velocity Proxy (tested on 3.4.0-SNAPSHOT)
• MySQL or MariaDB

Setup

1. Install the plugin
   Place the shaded JAR into your plugins/ folder on your Velocity proxy.

2. Configure MySQL and Discord
   On first run, plugins/sentinel/config.json will be created. Fill in your database credentials, Discord token, and optionally configure quarantine and staff roles:

   {
     "mysql": {
       "host": "localhost",
       "port": 3306,
       "database": "sentinel",
       "username": "sentinel_user",
       "password": "password"
     },
     "discord": {
       "token": "your_discord_bot_token",
       "linkedRole": "123456789012345678",
       "quarantineRole": "987654321098765432",
       "quarantineMessage": "Your account has been quarantined. Contact an administrator.",
       "staffRoles": ["111111111111111111", "222222222222222222"]
     },
     "bypassServers": {
       "servers": ["lobby", "auth"]
     }
   }

Configuration Options

• bypassServers: Server names that bypass Discord verification requirement. Useful for lobbies or auth servers where unverified players should be allowed.

• linkedRole: (Optional) Discord role ID automatically assigned to all linked players. When configured:

  • All existing linked accounts receive the role on bot startup (rate-limited)
  • New accounts that link immediately receive the role
  • Role synchronization spreads over ~20 minutes for large databases

• quarantineRole: (Optional) Discord role ID for quarantined players. When configured:

  • Applied/removed automatically when quarantines are added/removed
  • Used for Discord channel restrictions and effects
  • NOT used for login blocking - only database quarantines block login
  • Online players are immediately kicked when quarantined
  • Supports temporary bans with custom durations and reasons

• quarantineMessage: Default message shown to quarantined players (overridden by custom quarantine messages with details)

• staffRoles: Array of Discord role IDs that can use the /quarantine command