node-haxball/examples/plugins/consoleHelper.js

The most powerful and lightweight API that allows you to develop your original Haxball(www.haxball.com) host, client, and standalone applications both on node.js and browser environments and also includes every possible hack and functionality that you can

const vm = require("vm"); // you need to install this package manually in order to use it. (npm install vm)

module.exports = function(API){
  const { OperationType, VariableType, ConnectionState, AllowFlags, Direction, CollisionFlags, CameraFollow, BackgroundType, GamePlayState, BanEntryType, Callback, Utils, Room, Replay, Query, Library, RoomConfig, Plugin, Renderer, Errors, Language, EventFactory, Impl } = API;

  Object.setPrototypeOf(this, Plugin.prototype);
  Plugin.call(this, "consoleHelper", true, { // "consoleHelper" is plugin's name, "true" means "activated just after initialization". Every plugin should have a unique name.
    version: "0.1",
    author: "abc",
    description: `This plugin lets us write commands in the console and executes them. We do not need this inside a browser, this is useful for node.js. Only commands inside the room object are supported.
    Example usage: If you want to use room.setKeyState(5), just write setKeyState(5) and press enter.`,
    allowFlags: AllowFlags.CreateRoom | AllowFlags.JoinRoom // We allow this plugin to be activated on both CreateRoom and JoinRoom.
  });

  var that = this, stdin, listener = function(d) {
    try {
      vm.runInContext(d.toString().trim(), that.room); // process the string as a command in the room context.
    } catch (err) {
      console.error(`Error while executing the command: ${err}`);
    }
  };

  this.initialize = function(){
    vm.createContext(that.room); // setup context for room object.
    stdin = process.openStdin(); // read from standard input (console, in this case)
    stdin.addListener("data", listener); // triggered when we press enter in console.
  };

  this.finalize = function(){
    stdin.removeListener("data", listener);
    listener = null;
    stdin = null;
  };
};