implement chat logger

.gitignore

@@ -2,4 +2,5 @@ dist/
 node_modules/
 /*.png
 /*.db
+/*.log
 /config.toml

src/server/game.ts

@@ -3,6 +3,7 @@ import { RequestHandler } from 'express';
 import { IcyNetUser } from '../common/types/user';
 import { CharacterPacket, PositionUpdatePacket } from '../common/types/packet';
 import { Persistence } from './object/persistence';
+import { Logger } from './object/logger';
 
 const PLACEHOLDER_USER = (socket: Socket): IcyNetUser => {
   const randomName = `player-${socket.id.substring(0, 8)}`;
@@ -19,6 +20,7 @@ export class Game {
   private _connections: Socket[] = [];
   private _changedPlayers: number[] = [];
   private _db = new Persistence();
+  private _log = new Logger();
 
   constructor(private io: Server, private session: RequestHandler) {}
 
@@ -32,6 +34,7 @@ export class Game {
 
   async initialize() {
     await this._db.initialize();
+    this._log.initialize();
 
     this.io.use((socket, next) =>
       this.session(socket.request as any, {} as any, next as any),
@@ -57,6 +60,7 @@ export class Game {
 
       if (user) {
         socket.broadcast.emit('playerjoin', publicUserInfo);
+        this._log.writeEvent('PlayerJoin', `<${user.display_name}:${user.id}>`);
 
         socket.data.user = user;
         socket.data.playerinfo = {
@@ -89,6 +93,7 @@ export class Game {
 
         socket.on('chat-send', (raw) => {
           const message = raw.trim().substring(0, 280);
+          this._log.writeChat(user, message);
           this.io.emit('chat', { sender: publicUserInfo, message });
         });
 
@@ -138,6 +143,10 @@ export class Game {
 
         if (user) {
           this.io.emit('playerleave', publicUserInfo);
+          this._log.writeEvent(
+            'PlayerLeave',
+            `<${user.display_name}:${user.id}>`,
+          );
           this._db.upsertPony(user, socket.data.playerinfo);
         }
       });

src/server/object/logger.ts

@@ -0,0 +1,55 @@
+import { join } from 'path';
+import fs from 'fs';
+import { IcyNetUser } from '../../common/types/user';
+
+export class Logger {
+  private _stream!: fs.WriteStream;
+
+  constructor(private _path = join(process.cwd(), 'chat.log')) {}
+
+  initialize() {
+    this._stream = fs.createWriteStream(this._path, {
+      flags: 'a',
+      encoding: 'utf-8',
+    });
+  }
+
+  /**
+   * Write a chat message to the log file.
+   * @param user Sender
+   * @param message Message
+   */
+  writeChat(user: IcyNetUser, message: string) {
+    const date = this._createTimestamp(new Date());
+    const userStamp = `${user.display_name}:${user.id}`;
+    const fullStamp = `${date} <${userStamp}> ${message}`;
+    this._stream.write(`${fullStamp}\n`);
+  }
+
+  /**
+   * Write a server event to the log file.
+   * @param event Event name
+   * @param message Event description
+   */
+  writeEvent(event: string, message: string) {
+    const date = this._createTimestamp(new Date());
+    this._stream.write(`${date} %EVENT:${event}% ${message}\n`);
+  }
+
+  /**
+   * Returns timestamp in `YYYY/MM/DD HH:mm:ss` format.
+   * @param date Message time
+   * @returns Message timestamp
+   */
+  private _createTimestamp(date: Date): string {
+    const az = (n: number) => n.toString().padStart(2, '0');
+    const dateStamp = [date.getFullYear(), date.getMonth() + 1, date.getDate()]
+      .map(az)
+      .join('/');
+
+    const timeStamp = [date.getHours(), date.getMinutes(), date.getSeconds()]
+      .map(az)
+      .join(':');
+    return `[${dateStamp} ${timeStamp}]`;
+  }
+}