node-haxball/examples/plugins/CMD_breakConnection.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

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, "CMD_breakConnection", true, { // "breakConnection" 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 can make a player leave not by kicking him, but by breaking his connection. This should be improved with a permission mechanism.
    Available commands: 
    - !breakKick [id]: Break the connection of the player whose playerId=[id].`,
    allowFlags: AllowFlags.CreateRoom // We allow this plugin to be activated on CreateRoom only.
  });

  var connectionShouldBreak, permissionCtx, permissionIds, that = this;

  this.initialize = function(){
    connectionShouldBreak = {};
    permissionCtx = that.room.librariesMap.permissions?.createContext("breakConnection");
    if (permissionCtx)
      permissionIds = {
        breakKick: permissionCtx.addPermission("breakKick")
      };
    that.room.librariesMap.commands?.add({
      name: "breakKick",
      parameters: [{
        name: "playerId",
        type: VariableType.Integer,
        range: {
          min: 0
        }
      }],
      minParameterCount: 1,
      helpText: "Breaks the connection of a player, effectively kicking the player without actually kicking him/her.",
      callback: ({playerId}, byId) => {
        if (byId!=0 && !permissionCtx?.checkPlayerPermission(byId, permissionIds.breakKick)){
          that.room.librariesMap.commands?.announcePermissionDenied(byId);
          return;
        }
        connectionShouldBreak[playerId] = true; // mark player
      }
    });
  };

  this.finalize = function(){
    that.room.librariesMap.commands?.remove("breakKick");
    that.room.librariesMap.permissions?.removeContext(permissionCtx);
    connectionShouldBreak = null;
    permissionCtx = null;
    permissionIds = null;
  };

  this.onOperationReceived = function(type, msg, globalFrameNo, clientFrameNo, customData){ // this is host-only
    if (connectionShouldBreak[msg.byId]) // if player is marked
      throw ""; // connection is broken here. playerId will leave by himself without triggering a kick/ban event.
    return true;
  };

  this.onPlayerLeave = function(playerObj, reason, isBanned, byId, customData){
    // free extra memory allocated
    delete connectionShouldBreak[playerObj.id];
  };
};