Phantom Panel

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

Architecture

Phantom Panel is built on what I'm calling a Server-Agent architecture:

• The Server is provides a web interface, persists data in a database, and sends commands to the Agents.
• One or more Agents receive commands from the Server, manage the Minecraft server processes, and report on their status.

This architecture has several goals and benefits:

1. The Server and Agents can run on separate computers, in separate containers, or a mixture of both.
2. The Server and Agents can be updated independently.
   • The Server can receive new features, bug fixes, and security updates without the need to shutdown every Minecraft server.
   • Agent updates can be staggered or delayed. For example, if you have Agents in different geographical locations, you could schedule around timezones and update them at times 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 Server 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 Server), but if there is an Agent update that is compatible with older Servers, 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 two target images: phantom-server and phantom-agent.

Both images put the built application into the /app folder. The Agent image also installs Java 8, 16, 17, and 18.

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

Server

The Server comprises 3 key areas:

• Web server that provides the web interface.
• RPC server that Agents connect to.
• Database connection that requires a PostgreSQL database server in order to persist data.

The configuration for these is set via environment variables.

Agent Key

When the Server starts for the first time, it will generate and an Agent Key. The Agent Key contains an encryption certificate and an authorization token, which are needed for the Agents to connect to the Server.

The Agent Key has two forms:

• A binary file stored in /data/secrets/agent.key that the Agents can read.
• A plaintext-encoded version the Server outputs into the logs on every startup, that can be passed to the Agents in an environemnt variable.

Storage

Use volumes to persist the whole /data folder.

Environment variables

• 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: /
• RPC Server
  • RPC_SERVER_HOST is the host. Default: 0.0.0.0
  • RPC_SERVER_PORT is the port. Default: 9401
• PostgreSQL Database Server
  • 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:

• Server Communication
  • SERVER_HOST is the hostname of the Server.
  • SERVER_PORT is the RPC port of the Server. Default: 9401
  • AGENT_NAME is the display name of the Agent. Emoji are allowed.
  • AGENT_KEY is the plaintext-encoded version of Agent Key.
  • AGENT_KEY_FILE is a path to the Agent Key binary file.
• 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
• 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

Logging

Both the Server and Agent 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. 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: 9402
   • 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 and use one of the provided run configurations:
   • Server starts the Server.
   • Agent 1, Agent 2, Agent 3 start one of the Agents.
   • Server + Agent starts the Server and Agent 1.
   • Server + Agent x3 starts the Server and Agent 1, 2, and 3.

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.