pomelo源码解析--新建项目(cli工具: pomelo)

pomelo怎么新建项目

官方文档
1. 安装pomelo
2. 新建项目HelloWorld
我简单整理了下创建新项目关键步骤：

安装pomelo

方式一：
$ npm install pomelo -g
·
方式二：
$ git clone https://github.com/NetEase/pomelo.git
$ cd pomelo
$ npm install -g
·
注：如果npm安装特别慢，安装国内淘宝镜像cnpm，此后的命令我们可以用cnpm 来替代 npm。安装命令如下：
npm install -g cnpm --registry=https://registry.npm.taobao.org

新建项目HelloWorld

$ mkdir HelloWorld
$ cd HelloWorld
$ pomelo init

按照这些执行完我们最终成功创建了一个名叫HelloWorld的新项目：

npm下载安装、发布

为什么执行npm install pomelo -g就可以安装pomelo模块？为什么简单执行pomelo init就可以新建一个项目了？这些命令怎么来的？内部做了什么操作？
要搞清这些疑问之前，我们要先了解下nodejs如何编写、发布cli命令行工具
参考：https://blog.csdn.net/weixin_43254265/article/details/84797130

了解完npm怎么发布、安装包后，下面我们来分析下pomelo init源码实现流程：
首先我们可以看到pomelo源码中package.json配置中bin键

"bin": {"pomelo": "./bin/pomelo"},

执行pomelo实际运行的是/bin/pomelo，然后看下里面的pomelo init命令

// program = require('commander');
program.command('init [path]').description('create a new application').action(function(path) {init(path || CUR_DIR);
});

最后执行的init函数

function init(path) {console.log(INIT_PROJ_NOTICE);connectorType(function(type) { // 交互式命令(可用inquirer)，用户输入选择客户端使用的协议连接组件，然后回调返回emptyDirectory(path, function(empty) { // 判断path目录是否为空目录，默认命令执行的当前目录if(empty) {process.stdin.destroy();createApplicationAt(path, type);  // 这里创建项目了，做了一系列复制、删除、替换操作} else {confirm('Destination is not empty, continue? (y/n) [no] ', function(force) {process.stdin.destroy();if(force) {createApplicationAt(path, type);} else {abort('Fail to init a project'.red);}});}});});
}

/*** Create directory and files at the given directory `path`.** @param {String} ph*/
function createApplicationAt(ph, type) {var name = path.basename(path.resolve(CUR_DIR, ph));copy(path.join(__dirname, '../template/'), ph);mkdir(path.join(ph, 'game-server/logs'));mkdir(path.join(ph, 'shared'));// rmdir -rvar rmdir = function(dir) {var list = fs.readdirSync(dir);for(var i = 0; i < list.length; i++) {var filename = path.join(dir, list[i]);var stat = fs.statSync(filename);if(filename === "." || filename === "..") {} else if(stat.isDirectory()) {rmdir(filename);} else {fs.unlinkSync(filename);}}fs.rmdirSync(dir);};setTimeout(function() {switch(type) {case '1':// use websocketvar unlinkFiles = ['game-server/app.js.sio','game-server/app.js.wss','game-server/app.js.mqtt','game-server/app.js.sio.wss','game-server/app.js.udp','web-server/app.js.https','web-server/public/index.html.sio','web-server/public/js/lib/pomeloclient.js','web-server/public/js/lib/pomeloclient.js.wss','web-server/public/js/lib/build/build.js.wss','web-server/public/js/lib/socket.io.js'];for(var i = 0; i < unlinkFiles.length; ++i) {fs.unlinkSync(path.resolve(ph, unlinkFiles[i]));}break;case '2':// use socket.iovar unlinkFiles = ['game-server/app.js','game-server/app.js.wss','game-server/app.js.udp','game-server/app.js.mqtt','game-server/app.js.sio.wss','web-server/app.js.https','web-server/public/index.html','web-server/public/js/lib/component.json','web-server/public/js/lib/pomeloclient.js.wss'];for(var i = 0; i < unlinkFiles.length; ++i) {fs.unlinkSync(path.resolve(ph, unlinkFiles[i]));}fs.renameSync(path.resolve(ph, 'game-server/app.js.sio'), path.resolve(ph, 'game-server/app.js'));fs.renameSync(path.resolve(ph, 'web-server/public/index.html.sio'), path.resolve(ph, 'web-server/public/index.html'));rmdir(path.resolve(ph, 'web-server/public/js/lib/build'));rmdir(path.resolve(ph, 'web-server/public/js/lib/local'));break;case '3':// use websocket wssvar unlinkFiles = ['game-server/app.js.sio','game-server/app.js','game-server/app.js.udp','game-server/app.js.sio.wss','game-server/app.js.mqtt','web-server/app.js','web-server/public/index.html.sio','web-server/public/js/lib/pomeloclient.js','web-server/public/js/lib/pomeloclient.js.wss','web-server/public/js/lib/build/build.js','web-server/public/js/lib/socket.io.js'];for(var i = 0; i < unlinkFiles.length; ++i) {fs.unlinkSync(path.resolve(ph, unlinkFiles[i]));}fs.renameSync(path.resolve(ph, 'game-server/app.js.wss'), path.resolve(ph, 'game-server/app.js'));fs.renameSync(path.resolve(ph, 'web-server/app.js.https'), path.resolve(ph, 'web-server/app.js'));fs.renameSync(path.resolve(ph, 'web-server/public/js/lib/build/build.js.wss'), path.resolve(ph, 'web-server/public/js/lib/build/build.js'));break;case '4':// use socket.io wssvar unlinkFiles = ['game-server/app.js.sio','game-server/app.js','game-server/app.js.udp','game-server/app.js.wss','game-server/app.js.mqtt','web-server/app.js','web-server/public/index.html','web-server/public/js/lib/pomeloclient.js'];for(var i = 0; i < unlinkFiles.length; ++i) {fs.unlinkSync(path.resolve(ph, unlinkFiles[i]));}fs.renameSync(path.resolve(ph, 'game-server/app.js.sio.wss'), path.resolve(ph, 'game-server/app.js'));fs.renameSync(path.resolve(ph, 'web-server/app.js.https'), path.resolve(ph, 'web-server/app.js'));fs.renameSync(path.resolve(ph, 'web-server/public/index.html.sio'), path.resolve(ph, 'web-server/public/index.html'));fs.renameSync(path.resolve(ph, 'web-server/public/js/lib/pomeloclient.js.wss'), path.resolve(ph, 'web-server/public/js/lib/pomeloclient.js'));rmdir(path.resolve(ph, 'web-server/public/js/lib/build'));rmdir(path.resolve(ph, 'web-server/public/js/lib/local'));fs.unlinkSync(path.resolve(ph, 'web-server/public/js/lib/component.json'));break;case '5':// use socket.io wssvar unlinkFiles = ['game-server/app.js.sio','game-server/app.js','game-server/app.js.wss','game-server/app.js.mqtt','game-server/app.js.sio.wss','web-server/app.js.https','web-server/public/index.html','web-server/public/js/lib/component.json','web-server/public/js/lib/pomeloclient.js.wss'];for(var i = 0; i < unlinkFiles.length; ++i) {fs.unlinkSync(path.resolve(ph, unlinkFiles[i]));}fs.renameSync(path.resolve(ph, 'game-server/app.js.udp'), path.resolve(ph, 'game-server/app.js'));rmdir(path.resolve(ph, 'web-server/public/js/lib/build'));rmdir(path.resolve(ph, 'web-server/public/js/lib/local'));break;case '6':// use socket.iovar unlinkFiles = ['game-server/app.js','game-server/app.js.wss','game-server/app.js.udp','game-server/app.js.sio','game-server/app.js.sio.wss','web-server/app.js.https','web-server/public/index.html','web-server/public/js/lib/component.json','web-server/public/js/lib/pomeloclient.js.wss'];for(var i = 0; i < unlinkFiles.length; ++i) {fs.unlinkSync(path.resolve(ph, unlinkFiles[i]));}fs.renameSync(path.resolve(ph, 'game-server/app.js.mqtt'), path.resolve(ph, 'game-server/app.js'));fs.renameSync(path.resolve(ph, 'web-server/public/index.html.sio'), path.resolve(ph, 'web-server/public/index.html'));rmdir(path.resolve(ph, 'web-server/public/js/lib/build'));rmdir(path.resolve(ph, 'web-server/public/js/lib/local'));break;}var replaceFiles = ['game-server/app.js','game-server/package.json','web-server/package.json'];for(var j = 0; j < replaceFiles.length; j++) {var str = fs.readFileSync(path.resolve(ph, replaceFiles[j])).toString();fs.writeFileSync(path.resolve(ph, replaceFiles[j]), str.replace('$', name));}var f = path.resolve(ph, 'game-server/package.json');var content = fs.readFileSync(f).toString();fs.writeFileSync(f, content.replace('#', version));}, TIME_INIT);
}

这样就生成了我们上面截图的HelloWorld项目了！至于其它pomelo stop、list、add、kill、restart、masterha等命令原理一样，可自行了解下。