pomelo源碼分析(一)

        千裡之行始於足下，一直說想瞭解pomelo，對pomelo有興趣，但一直遲遲沒有去碰，雖然對pomelo進行源碼分析，在網路上肯定不止我一個，已經有很優秀的前輩走在前面，如http://golanger.cn/，在閱讀Pomelo代碼的時候，已經連載到了11篇了，在我的源碼分析參考了該部落格，當然，也會加入我對pomelo的理解，藉此希望能提高一下自己對node.js的瞭解和學習一些優秀的設計。

開發環境：win7 調試環境：webstorm5.0 node.js版本：v0.8.21 源碼版本package.json：

{"name": "chatofpomelo","version": "0.0.1","private": false,"dependencies": {"pomelo": "0.2.0","log4js": ">= 0.4.1","crc": ">=0.0.1"}}

gameserver/app.js

var pomelo = require('pomelo');var routeUtil = require('./app/util/routeUtil');/** * Init app for client. */var app = pomelo.createApp();     //建立Applicationapp.set('name', 'chatofpomelo');  //設定Application名字// app configure  app.configure('production|development', function() {  // route configuresapp.route('chat', routeUtil.chat);// filter configuresapp.filter(pomelo.timeout());});// start appapp.start();process.on('uncaughtException', function(err) {console.error(' Caught exception: ' + err.stack);});

注意：在webstorm下調試，可能因為工作目錄的設定原因會導致應用的執行路徑問題，導致無法讀取設定檔，所以需要根據實際情況修改如下

var opt = {'base':'D:\\src\\pomelo\\chatofpomelo\\game-server'}var app = pomelo.createApp(opt);app.set('name', 'chatofpomelo');

opt.base 是你的game-server的實際目錄路徑，具體可以根據自己需要來定製

app.js 是game-server的主要入口，主要負責建立application，讀取設定檔，應用到application設定上，並利用app.start()來執行實際的master，monitor等伺服器的start，對於聊天室程式來說，還要做簡單的路由和過濾設定。

application, 應用的定義、component管理，上下文配置， 這些使pomelo framework的對外介面很簡單， 並且具有松耦合、可插拔架構。

所有伺服器的啟動都是從運行app.js開始。每一個伺服器的啟動都首先建立一個全域唯一的application對象，該對象中掛載了所在伺服器的所有資訊，包括伺服器物理資訊、伺服器邏輯資訊、以及pomelo的組件資訊等。同時，該對象還提供應用管理和配置等基本方法。 在app.js中調用app.start()方法後，application對象首先會通過loadDefaultComponents方法載入預設的組件。

pomelo/lib/pomelo.js

var application = require('./application');Pomelo.createApp = function (opts) {  var app = application;  app.init(opts);  self.app = app;  return app;};

pomelo/lib/application.js

/** * Application prototype. * * @module */var Application = module.exports = {};/** * Application states */var STATE_INITED  = 1;  // app has initedvar STATE_START = 2;  // app startvar STATE_STARTED = 3;  // app has startedvar STATE_STOPED  = 4;  // app has stoped/** * Initialize the server. * *   - setup default configuration * * @api private */Application.init = function(opts) {  opts = opts || {};  logger.info('app.init invoked');  this.loaded = [];  this.components = {};  this.settings = {};   // set，和get功能的容器  this.set('base', opts.base);  //設定伺服器的工作目錄  this.defaultConfiguration();  //根據設定檔，載入master，monitor等伺服器  this.state = STATE_INITED;  //application工作狀態  logger.info('application inited: %j', this.get('serverId'));};

pomelo/lib/application.js

/** * Initialize application configuration. * * @api private */Application.defaultConfiguration = function () {  var args = utils.argsInfo(process.argv);  this.setupEnv(args); //application環境設定  this.loadServers();  //載入伺服器配置資訊  this.loadConfig('master', this.getBase() + '/config/master.json'); //載入mater伺服器配置資訊  this.processArgs(args); //根據啟動參數設定伺服器配置  this.configLogger();};

utils.argsInfo(process.argv); 擷取系統啟動參數，我們不妨看看到底有哪些參數支援 

啟動game-server伺服器：>pomelo start [development | production] [--daemon]

根據args參數設定application的工作環境是development或production

/** * Setup enviroment. * @api private */Application.setupEnv = function(args) {  this.set('env', args.env || process.env.NODE_ENV || 'development', true);};

載入伺服器資訊，並且儲存在__serverMap___記憶體下

/** * Load server info from configure file. * * @api private */Application.loadServers = function() {  this.loadConfig('servers', this.getBase() + '/config/servers.json');  var servers = this.get('servers');  var serverMap = {}, slist, i, l, server;  for(var serverType in servers) {    slist = servers[serverType];    for(i=0, l=slist.length; i<l; i++) {      server = slist[i];      server.serverType = serverType;      serverMap[server.id] = server;    }  }  this.set('__serverMap__', serverMap);};

server.json

{    "development":{        "connector":[             {"id":"connector-server-1", "host":"127.0.0.1", "port":4050, "wsPort":3050},             {"id":"connector-server-2", "host":"127.0.0.1", "port":4051, "wsPort":3051},             {"id":"connector-server-3", "host":"127.0.0.1", "port":4052, "wsPort":3052}         ],        "chat":[             {"id":"chat-server-1", "host":"127.0.0.1", "port":6050},             {"id":"chat-server-2", "host":"127.0.0.1", "port":6051},             {"id":"chat-server-3", "host":"127.0.0.1", "port":6052}        ],        "gate":[     {"id": "gate-server-1", "host": "127.0.0.1", "wsPort": 3014}]    },    "production":{       "connector":[             {"id":"connector-server-1", "host":"127.0.0.1", "port":4050, "wsPort":3050},             {"id":"connector-server-2", "host":"127.0.0.1", "port":4051, "wsPort":3051},             {"id":"connector-server-3", "host":"127.0.0.1", "port":4052, "wsPort":3052}         ],        "chat":[             {"id":"chat-server-1", "host":"127.0.0.1", "port":6050},             {"id":"chat-server-2", "host":"127.0.0.1", "port":6051},             {"id":"chat-server-3", "host":"127.0.0.1", "port":6052}        ],        "gate":[     {"id": "gate-server-1", "host": "127.0.0.1", "wsPort": 3014}]  }}

工具函數，讀取json設定檔，在這裡讀取的是master.json檔案

/** * Load Configure json file to settings. * * @param {String} key environment key * @param {String} val environment value * @return {Server|Mixed} for chaining, or the setting value * * @memberOf Application */Application.loadConfig = function (key, val) {  var env = this.get('env');  val = require(val);  if (val[env]) {    val = val[env];  }  this.set(key, val);};

master.json

{    "development":{        "id":"master-server-1",        "host":"127.0.0.1",        "port":3005,        "queryPort":3015,        "wsPort":2337    },    "production":{        "id":"master-server-1",        "host":"127.0.0.1",        "port":3005,        "queryPort":3015,        "wsPort":2337    }}

根據進程讀取配置好的參數，設定管理員。

Application.processArgs = function(args){  var serverType = args.serverType || 'master';  var serverId = args.serverId || this.get('master').id;  this.set('main', args.main, true);  this.set('serverType', serverType, true);  this.set('serverId', serverId, true);  if(serverType !== 'master') {    this.set('curServer', this.getServerById(serverId), true);  } else {    this.set('curServer', this.get('master'), true);  }};

項目的日誌配置

Application.configLogger = function() {  if(process.env.POMELO_LOGGER !== 'off') {    log.configure(this, this.getBase() + '/config/log4js.json');  }};

log4js.json

{  "appenders": [    {      "type": "file",      "filename": "./logs/node-log-${opts:serverId}.log",      "fileSize": 1048576,      "layout": {        "type": "basic"      },       "backups": 5    },    {      "type": "console"    },    {      "type": "file",      "filename": "./logs/con-log-${opts:serverId}.log",       "pattern": "connector",       "fileSize": 1048576,      "layout": {          "type": "basic"        }      ,"backups": 5,      "category":"con-log"    },    {      "type": "file",      "filename": "./logs/rpc-log-${opts:serverId}.log",      "fileSize": 1048576,      "layout": {          "type": "basic"        }      ,"backups": 5,      "category":"rpc-log"    },    {      "type": "file",      "filename": "./logs/forward-log-${opts:serverId}.log",      "fileSize": 1048576,      "layout": {          "type": "basic"        }      ,"backups": 5,      "category":"forward-log"    },    {      "type": "file",      "filename": "./logs/crash.log",      "fileSize": 1048576,      "layout": {          "type": "basic"        }      ,"backups": 5,      "category":"crash-log"    }  ],  "levels": {  "rpc-log" : "ERROR",     "forward-log": "ERROR"  },   "replaceConsole": true}