ViaProxyVBUCheck

A ViaProxy plugin that detects whether the ViaBedrockUtility mod is installed on the client when connecting to Bedrock servers, and notifies players to install it if missing.

Features

• Detects ViaBedrockUtility mod presence via custom payload channel registration
• Triggers precisely when the player enters the world (not a simple timer), by intercepting the first PLAY-state packet (JoinGame)
• Only activates for Bedrock server connections
• Two notification modes based on client version:
  • 1.21.6+: Native Minecraft Dialog popup
  • Older versions: Chat message with clickable download URL
• Fully configurable message text, download URL, and dialog appearance

Installation

1. Download the latest VBUCheck-x.x.x.jar from Releases
2. Place the JAR in ViaProxy's plugins/ directory
3. Start ViaProxy — a default config.yml will be generated in plugins/VBUCheck/

Building from Source

Requires ViaProxy and ViaBedrock published to mavenLocal:

# In ViaVersion directory
./gradlew publishToMavenLocal

# In ViaBedrock directory
./gradlew publishToMavenLocal

# Then build the plugin
./gradlew build

The output JAR will be at build/libs/VBUCheck-1.0.0.jar.

Configuration

On first run, plugins/VBUCheck/config.yml is generated:

# Enable/disable the check
enabled: true

# Delay in milliseconds after entering the world before sending the notification (0 = immediate)
delay-ms: 1000

# Notification message text
message: "检测到您未安装 ViaBedrockUtility Mod，部分功能（自定义实体、皮肤等）将无法正常显示。请安装该 Mod 以获得最佳体验。"

# Download URL (clickable in chat messages for pre-1.21.6 clients)
download-url: "https://github.com/RaphiMC/ViaBedrockUtility/releases"

# Dialog title (1.21.6+ only)
dialog-title: "提示"

# Dialog close button text (1.21.6+ only)
dialog-close-button: "我知道了"

How It Works

1. On ConnectEvent, the plugin checks if the target is a Bedrock server and registers a custom PacketHandler
2. The handler monitors server-to-client packets via handleP2S() and detects the first PLAY-state packet (the JoinGame packet), which indicates the player has entered the world
3. After an optional configurable delay, it checks ChannelStorage for the viabedrockutility:confirm channel — which ViaBedrockUtility registers during the CONFIGURATION phase
4. If the channel is not found, it sends a Dialog (1.21.6+) or a system chat message (older versions) to the player

License

This project is open source under the MIT License.