Phantom Panel

Phantom Panel is a work-in-progress web interface for managing Minecraft servers.

Architecture

Phantom Panel has 3 types of services:

• The Web provides a web interface for the Controller.
• The Controller manages all state and persists it in a database, and communicates with Agents.
• One or more Agents receive commands from the Controller, manage the Minecraft server processes, and report on their status.

This architecture has several goals and benefits:

1. The services can run on separate computers, in separate containers, or a mixture of both.
2. The services can be updated independently.
   • The Controller or Web can receive updates without the need to shut down every Minecraft server.
   • Agent updates can be staggered or delayed. For example, if the Agents are in different geographical locations, each can be updated at a time when people are unlikely to be online.
3. Agents are lightweight processes which should have minimal impact on the performance of Minecraft servers.

When an official Controller update is released, it will work with older versions of Agents. There is no guarantee it will also work in reverse (updated Agents and an older Controller), but if there is an Agent update that is compatible with an older Controller, it will be mentioned in the release notes.

Note that compatibility is only guaranteed when using official releases. If you build the project from a version of the source between two official releases, you have to understand which changes break compatibility.

Usage

This project is work-in-progress, and currently has no official releases. Feel free to try it and experiment, but there will be missing features, bugs, and breaking changes.

For a quick start, I recommend using Docker or another containerization platform. The Dockerfile in the root of the repository can build three target images: phantom-web, phantom-controller, and phantom-agent.

All images put the built application into the /app folder. The Agent image includes Java 8, 16, 17, and 21.

Files are stored relative to the working directory. In the provided images, the working directory is set to /data.

Important

The 3 services communicate with each other using TLS. Due to inconsistent TLS support and implementation quirks between operating systems, Phantom Panel is intended to run only on Linux with up-to-date OpenSSL libraries. Support for other operating systems only exists for the purposes of local development, and components running on different operating systems may not be able to communicate with each other.

Controller

The Controller comprises 3 key areas:

• Agent RPC server that Agents connect to.
• Web RPC server that the Web connects to.
• PostgreSQL database connection to persist data.

The configuration for these is set via environment variables.

Secrets

Each Agent requires its own Agent Key, and the Web server requires a Web Key. These must be passed to the services in an environment variable or a file.

When the Controller starts for the first time, it will generate two certificate files (agent.pfx and web.pfx), which are used for TLS communication, and a Web authentication token file (web.auth). These files must only be accessible to the Controller itself.

Since there is only one Web server, there is only one Web Key, which is generated from the Web certificate and authentication token files. The Controller prints the Web Key to standard output on every start. Agents and their Agent Keys are managed through the Web interface, and their authentication tokens are stored in the database.

Storage

Use volumes to persist the whole /data folder.

Environment variables

• Agent RPC Server
  • AGENT_RPC_SERVER_HOST is the host. Default: 0.0.0.0
  • AGENT_RPC_SERVER_PORT is the port. Default: 9401
• Web RPC Server
  • WEB_RPC_SERVER_HOST is the host. Default: 0.0.0.0
  • WEB_RPC_SERVER_PORT is the port. Default: 9402
• PostgreSQL Database Connection
  • PG_HOST is the hostname.
  • PG_PORT is the port.
  • PG_USER is the username.
  • PG_PASS is the password.
  • PG_DATABASE is the database name.

Agent

Storage

The /data folder will contain two folders:

• /data/data for persistent files
• /data/temp for volatile files (such as downloaded Minecraft .jar files)

Use volumes to persist either the whole /data folder, or just /data/data if you don't want to persist the volatile files.

Environment Variables

• Controller Communication
  • CONTROLLER_HOST is the hostname of the Controller.
  • CONTROLLER_PORT is the Agent RPC port of the Controller. Default: 9401
  • AGENT_KEY is the Agent Key. Mutually exclusive with AGENT_KEY_FILE.
  • AGENT_KEY_FILE is a path to a file containing the Agent Key. Mutually exclusive with AGENT_KEY.
• Agent Configuration
  • MAX_INSTANCES is the number of instances that can be created.
  • MAX_MEMORY is the maximum amount of RAM that can be distributed among all instances. Use a positive integer with an optional suffix 'M' for MB, or 'G' for GB. Examples: 4096M, 16G
  • MAX_CONCURRENT_BACKUP_COMPRESSION_TASKS is how many backup compression tasks can run at the same time. Limiting concurrent compression tasks limits memory usage of compression, but it increases time between backups because the next backup is only scheduled once the current one completes. Default: 1
• Minecraft Configuration
  • JAVA_SEARCH_PATH is a path to a folder which will be searched for Java runtime installations. Linux default: /usr/lib/jvm
  • ALLOWED_SERVER_PORTS is a comma-separated list of ports and port ranges that can be used as Minecraft Server ports. Example: 25565,25900,26000-27000
  • ALLOWED_RCON_PORTS is a comma-separated list of ports and port ranges that can be used as Minecraft RCON ports. Example: 25575,25901,36000-37000

Web

Storage

Use volumes to persist the whole /data folder.

Environment Variables

• Controller Communication
  • CONTROLLER_HOST is the hostname of the Controller.
  • CONTROLLER_PORT is the Web RPC port of the Controller. Default: 9402
  • WEB_KEY is the Web Key. Mutually exclusive with WEB_KEY_FILE.
  • WEB_KEY_FILE is a path to a file containing the Web Key. Mutually exclusive with WEB_KEY.
• Web Server
  • WEB_SERVER_HOST is the host. Default: 0.0.0.0
  • WEB_SERVER_PORT is the port. Default: 9400
  • WEB_BASE_PATH is the base path of every URL. Must begin with a slash. Default: /

Logging

All services support a LOG_LEVEL environment variable to set the minimum log level. Possible values:

• VERBOSE
• DEBUG
• INFORMATION
• WARNING
• ERROR

If the environment variable is omitted, the log level is set to VERBOSE for Debug builds and INFORMATION for Release builds.

Development

The repository includes a Rider projects with several run configurations. The .workdir folder in the root of the repository is used for storage, including secret files intended for development use only. Here's how to get started:

1. You will need a local PostgreSQL instance. If you have Docker, you can enter the Docker folder in this repository, and run docker compose up. Otherwise, you will need to set it up manually with the following configuration:
   • Host: localhost
   • Port: 9403
   • User: postgres
   • Password: development
   • Database: postgres
2. Install one or more Java versions into the ~/.jdks folder (%USERPROFILE%\.jdks on Windows).
3. Open the project in Rider.
4. Launch the Controller and Web run configurations.
5. Open the website and create an account.
6. Create 1-3 Agents on the website. For each, create a .workdir/AgentX/key file containing the respective Agent Key.
7. Launch any of the Agent 1, Agent 2, Agent 3 run configurations.

Bootstrap

The project uses Bootstrap 5 with a custom theme and several other customizations. The sources are in the Phantom.Server.Web.Bootstrap project.

If you make any changes to the sources, you will need to use the Compile Bootstrap run configuration, then restart the Server to load the new version. This is not done automatically, and it requires Node and npm.