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!config/default.* | ||
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results | ||
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N-blog | ||
====== | ||
## N-blog | ||
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使用 Express + MongoDB 搭建多人博客 | ||
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教程见 [book](https://github.com/nswbmw/N-blog/tree/backup/book) | ||
### 目录 | ||
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- 开发环境搭建 | ||
- [Node.js 的安装与使用](https://github.com/nswbmw/N-blog/blob/master/book/1.1%20Node.js%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md) | ||
- [安装 Node.js](https://github.com/nswbmw/N-blog/blob/master/book/1.1%20Node.js%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md#111-安装-nodejs) | ||
- [n 和 nvm](https://github.com/nswbmw/N-blog/blob/master/book/1.1%20Node.js%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md#112-n-和-nvm) | ||
- [nrm](https://github.com/nswbmw/N-blog/blob/master/book/1.1%20Node.js%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md#113-nrm) | ||
- [MongoDB 的安装与使用](https://github.com/nswbmw/N-blog/blob/master/book/1.2%20MongoDB%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md) | ||
- [安装与启动 MongoDB](https://github.com/nswbmw/N-blog/blob/master/book/1.2%20MongoDB%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md#121-安装与启动-mongodb) | ||
- [Robomongo 和 MongoChef](https://github.com/nswbmw/N-blog/blob/master/book/1.2%20MongoDB%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md#122-robomongo-和-mongochef) | ||
- Node.js 知识点讲解 | ||
- [require](https://github.com/nswbmw/N-blog/blob/master/book/2.1%20require.md) | ||
- [exports 和 module.exports](https://github.com/nswbmw/N-blog/blob/master/book/2.2%20exports%20%E5%92%8C%20module.exports.md) | ||
- [Promise](https://github.com/nswbmw/N-blog/blob/master/book/2.3%20Promise.md) | ||
- [环境变量](https://github.com/nswbmw/N-blog/blob/master/book/2.4%20%E7%8E%AF%E5%A2%83%E5%8F%98%E9%87%8F.md) | ||
- [packge.json](https://github.com/nswbmw/N-blog/blob/master/book/2.5%20package.json.md) | ||
- [semver](https://github.com/nswbmw/N-blog/blob/master/book/2.5%20package.json.md#251-semver) | ||
- [npm 使用注意事项](https://github.com/nswbmw/N-blog/blob/master/book/2.6%20npm%20%E4%BD%BF%E7%94%A8%E6%B3%A8%E6%84%8F%E4%BA%8B%E9%A1%B9.md) | ||
- [npm init](https://github.com/nswbmw/N-blog/blob/master/book/2.6%20npm%20%E4%BD%BF%E7%94%A8%E6%B3%A8%E6%84%8F%E4%BA%8B%E9%A1%B9.md#261-npm-init) | ||
- [npm install](https://github.com/nswbmw/N-blog/blob/master/book/2.6%20npm%20%E4%BD%BF%E7%94%A8%E6%B3%A8%E6%84%8F%E4%BA%8B%E9%A1%B9.md#262-npm-install) | ||
- [npm scripts](https://github.com/nswbmw/N-blog/blob/master/book/2.6%20npm%20%E4%BD%BF%E7%94%A8%E6%B3%A8%E6%84%8F%E4%BA%8B%E9%A1%B9.md#263-npm-scripts) | ||
- [npm shrinkwrap ](https://github.com/nswbmw/N-blog/blob/master/book/2.6%20npm%20%E4%BD%BF%E7%94%A8%E6%B3%A8%E6%84%8F%E4%BA%8B%E9%A1%B9.md#264-npm-shrinkwrap) | ||
- Hello, Express | ||
- [初始化一个 Express 项目](https://github.com/nswbmw/N-blog/blob/master/book/3.1%20%E5%88%9D%E5%A7%8B%E5%8C%96%E4%B8%80%E4%B8%AA%20Express%20%E9%A1%B9%E7%9B%AE.md) | ||
- [supervisor](https://github.com/nswbmw/N-blog/blob/master/book/3.1%20%E5%88%9D%E5%A7%8B%E5%8C%96%E4%B8%80%E4%B8%AA%20Express%20%E9%A1%B9%E7%9B%AE.md#311-supervisor) | ||
- [路由](https://github.com/nswbmw/N-blog/blob/master/book/3.2%20%E8%B7%AF%E7%94%B1.md) | ||
- [express.Router](https://github.com/nswbmw/N-blog/blob/master/book/3.2%20%E8%B7%AF%E7%94%B1.md#321-expressrouter) | ||
- [模板引擎](https://github.com/nswbmw/N-blog/blob/master/book/3.3%20%E6%A8%A1%E6%9D%BF%E5%BC%95%E6%93%8E.md) | ||
- [ejs](https://github.com/nswbmw/N-blog/blob/master/book/3.3%20%E6%A8%A1%E6%9D%BF%E5%BC%95%E6%93%8E.md#331-ejs) | ||
- [includes](https://github.com/nswbmw/N-blog/blob/master/book/3.3%20%E6%A8%A1%E6%9D%BF%E5%BC%95%E6%93%8E.md#332-includes) | ||
- [Express 浅析](https://github.com/nswbmw/N-blog/blob/master/book/3.4%20Express%20%E6%B5%85%E6%9E%90.md) | ||
- [中间件与 next](https://github.com/nswbmw/N-blog/blob/master/book/3.4%20Express%20%E6%B5%85%E6%9E%90.md#341-中间件与-next) | ||
- [错误处理](https://github.com/nswbmw/N-blog/blob/master/book/3.4%20Express%20%E6%B5%85%E6%9E%90.md#342-错误处理) | ||
- 一个简单的博客 | ||
- [开发环境](https://github.com/nswbmw/N-blog/blob/master/book/4.1%20%E5%BC%80%E5%8F%91%E7%8E%AF%E5%A2%83.md) | ||
- [准备工作](https://github.com/nswbmw/N-blog/blob/master/book/4.2%20%E5%87%86%E5%A4%87%E5%B7%A5%E4%BD%9C.md) | ||
- [目录结构](https://github.com/nswbmw/N-blog/blob/master/book/4.2%20%E5%87%86%E5%A4%87%E5%B7%A5%E4%BD%9C.md#421-目录结构) | ||
- [安装依赖模块](https://github.com/nswbmw/N-blog/blob/master/book/4.2%20%E5%87%86%E5%A4%87%E5%B7%A5%E4%BD%9C.md#422-安装依赖模块) | ||
- [配置文件](https://github.com/nswbmw/N-blog/blob/master/book/4.3%20%E9%85%8D%E7%BD%AE%E6%96%87%E4%BB%B6.md) | ||
- [config-lite](https://github.com/nswbmw/N-blog/blob/master/book/4.3%20%E9%85%8D%E7%BD%AE%E6%96%87%E4%BB%B6.md#431-config-lite) | ||
- [功能设计](https://github.com/nswbmw/N-blog/blob/master/book/4.4%20%E5%8A%9F%E8%83%BD%E8%AE%BE%E8%AE%A1.md) | ||
- [功能与路由设计](https://github.com/nswbmw/N-blog/blob/master/book/4.4%20%E5%8A%9F%E8%83%BD%E8%AE%BE%E8%AE%A1.md#441-功能与路由设计) | ||
- [会话](https://github.com/nswbmw/N-blog/blob/master/book/4.4%20%E5%8A%9F%E8%83%BD%E8%AE%BE%E8%AE%A1.md#442-会话) | ||
- [页面通知](https://github.com/nswbmw/N-blog/blob/master/book/4.4%20%E5%8A%9F%E8%83%BD%E8%AE%BE%E8%AE%A1.md#443-页面通知) | ||
- [权限控制](https://github.com/nswbmw/N-blog/blob/master/book/4.4%20%E5%8A%9F%E8%83%BD%E8%AE%BE%E8%AE%A1.md#444-权限控制) | ||
- [页面设计](https://github.com/nswbmw/N-blog/blob/master/book/4.5%20%E9%A1%B5%E9%9D%A2%E8%AE%BE%E8%AE%A1.md) | ||
- [组件](https://github.com/nswbmw/N-blog/blob/master/book/4.5%20%E9%A1%B5%E9%9D%A2%E8%AE%BE%E8%AE%A1.md#451-组件) | ||
- [app.locals 和 res.locals](https://github.com/nswbmw/N-blog/blob/master/book/4.5%20%E9%A1%B5%E9%9D%A2%E8%AE%BE%E8%AE%A1.md#452-applocals-和-reslocals) | ||
- [连接数据库](https://github.com/nswbmw/N-blog/blob/master/book/4.6%20%E8%BF%9E%E6%8E%A5%E6%95%B0%E6%8D%AE%E5%BA%93.md) | ||
- [为什么使用 Mongolass](https://github.com/nswbmw/N-blog/blob/master/book/4.6%20%E8%BF%9E%E6%8E%A5%E6%95%B0%E6%8D%AE%E5%BA%93.md#461-为什么使用-mongolass) | ||
- [注册](https://github.com/nswbmw/N-blog/blob/master/book/4.7%20%E6%B3%A8%E5%86%8C.md) | ||
- [用户模型设计](https://github.com/nswbmw/N-blog/blob/master/book/4.7%20%E6%B3%A8%E5%86%8C.md#471-用户模型设计) | ||
- [注册页](https://github.com/nswbmw/N-blog/blob/master/book/4.7%20%E6%B3%A8%E5%86%8C.md#472-注册页) | ||
- [注册与文件上传](https://github.com/nswbmw/N-blog/blob/master/book/4.7%20%E6%B3%A8%E5%86%8C.md#473-注册与文件上传) | ||
- [登出与登录](https://github.com/nswbmw/N-blog/blob/master/book/4.8%20%E7%99%BB%E5%87%BA%E4%B8%8E%E7%99%BB%E5%BD%95.md) | ||
- [登出](https://github.com/nswbmw/N-blog/blob/master/book/4.8%20%E7%99%BB%E5%87%BA%E4%B8%8E%E7%99%BB%E5%BD%95.md#481-登出) | ||
- [登录页](https://github.com/nswbmw/N-blog/blob/master/book/4.8%20%E7%99%BB%E5%87%BA%E4%B8%8E%E7%99%BB%E5%BD%95.md#482-登录页) | ||
- [登录](https://github.com/nswbmw/N-blog/blob/master/book/4.8%20%E7%99%BB%E5%87%BA%E4%B8%8E%E7%99%BB%E5%BD%95.md#483-登录) | ||
- [文章](https://github.com/nswbmw/N-blog/blob/master/book/4.9%20%E6%96%87%E7%AB%A0.md) | ||
- [文章模型设计](https://github.com/nswbmw/N-blog/blob/master/book/4.9%20%E6%96%87%E7%AB%A0.md#491-文章模型设计) | ||
- [发表文章](https://github.com/nswbmw/N-blog/blob/master/book/4.9%20%E6%96%87%E7%AB%A0.md#492-发表文章) | ||
- [主页与文章页](https://github.com/nswbmw/N-blog/blob/master/book/4.9%20%E6%96%87%E7%AB%A0.md#493-主页与文章页) | ||
- [编辑与删除文章](https://github.com/nswbmw/N-blog/blob/master/book/4.9%20%E6%96%87%E7%AB%A0.md#494-编辑与删除文章) | ||
- [留言](https://github.com/nswbmw/N-blog/blob/master/book/4.10%20%E7%95%99%E8%A8%80.md) | ||
- [留言模型设计](https://github.com/nswbmw/N-blog/blob/master/book/4.10%20%E7%95%99%E8%A8%80.md#4101-留言模型设计) | ||
- [显示留言](https://github.com/nswbmw/N-blog/blob/master/book/4.10%20%E7%95%99%E8%A8%80.md#4102-显示留言) | ||
- [发表与删除留言](https://github.com/nswbmw/N-blog/blob/master/book/4.10%20%E7%95%99%E8%A8%80.md#4103-发表与删除留言) | ||
- [404页面](https://github.com/nswbmw/N-blog/blob/master/book/4.11%20404%20%E9%A1%B5%E9%9D%A2.md) | ||
- [错误页面](https://github.com/nswbmw/N-blog/blob/master/book/4.12%20%E9%94%99%E8%AF%AF%E9%A1%B5%E9%9D%A2.md) | ||
- [日志](https://github.com/nswbmw/N-blog/blob/master/book/4.13%20%E6%97%A5%E5%BF%97.md) | ||
- [winston 和 express-winston](https://github.com/nswbmw/N-blog/blob/master/book/4.13%20%E6%97%A5%E5%BF%97.md#4131-winston-和-express-winston) | ||
- [.gitignore](https://github.com/nswbmw/N-blog/blob/master/book/4.13%20%E6%97%A5%E5%BF%97.md#4132-gitignore) | ||
- [测试](https://github.com/nswbmw/N-blog/blob/master/book/4.14%20%E6%B5%8B%E8%AF%95.md) | ||
- [mocha 和 supertest](https://github.com/nswbmw/N-blog/blob/master/book/4.14%20%E6%B5%8B%E8%AF%95.md#4141-mocha-和-supertest) | ||
- [测试覆盖率](https://github.com/nswbmw/N-blog/blob/master/book/4.14%20%E6%B5%8B%E8%AF%95.md#4142-测试覆盖率) | ||
- [部署](https://github.com/nswbmw/N-blog/blob/master/book/4.15%20%E9%83%A8%E7%BD%B2.md) | ||
- [申请 MLab](https://github.com/nswbmw/N-blog/blob/master/book/4.15%20%E9%83%A8%E7%BD%B2.md#4151-申请-mlab) | ||
- [pm2](https://github.com/nswbmw/N-blog/blob/master/book/4.15%20%E9%83%A8%E7%BD%B2.md#4152-pm2) | ||
- [部署到 Heroku](https://github.com/nswbmw/N-blog/blob/master/book/4.15%20%E9%83%A8%E7%BD%B2.md#4152-部署到-heroku) | ||
- [部署到 UCloud](https://github.com/nswbmw/N-blog/blob/master/book/4.15%20%E9%83%A8%E7%BD%B2.md#4153-部署到-ucloud) |
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## 1.1.1 安装 Node.js | ||
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有三种方式安装 Node.js:一是通过安装包安装,二是通过源码编译安装,三是在 Linux 下可以通过 yum|apt-get 安装,在 Mac 下可以通过 [Homebrew](http://brew.sh/) 安装。对于 Windows 和 Mac 用户,推荐使用安装包安装,Linux 用户推荐使用源码编译安装。 | ||
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#### Windows 和 Mac 安装: | ||
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**第一步:** | ||
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打开 [Node.js 官网](https://nodejs.org/en/),可以看到以下两个下载选项: | ||
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![](./img/1.1.1.png) | ||
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左边的是 LTS 版,用过 ubuntu 的同学可能比较熟悉,即长期支持版本,大多数人用这个就可以了。右边是最新版,支持最新的语言特性(比如对 ES6 的支持更全面),想尝试新特性的开发者可以安装这个版本。我们选择左边的 v6.9.1 LTS 点击下载。 | ||
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> 小提示:从 [http://node.green](http://node.green) 上可以看到 Node.js 各个版本对 ES6 的支持情况。 | ||
**第二步:** | ||
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安装 Node.js,这个没什么好说的,一直点击 `继续` 即可。 | ||
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![](./img/1.1.2.png) | ||
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**第三步:** | ||
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提示安装成功后,打开终端输入以下命令,可以看到 node 和 npm 都已经安装好了: | ||
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![](./img/1.1.3.png) | ||
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#### Linux 安装: | ||
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Linux 用户可通过源码编译安装: | ||
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``` | ||
curl -O https://nodejs.org/dist/v6.9.1/node-v6.9.1.tar.gz | ||
tar -xzvf node-v6.9.1.tar.gz | ||
cd node-v6.9.1 | ||
./configure | ||
make | ||
make install | ||
``` | ||
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> 注意: 如果编译过程报错,可能是缺少某些依赖包。因为报错内容不尽相同,请读者自行求助搜索引擎或 [stackoverflow](http://stackoverflow.com/)。 | ||
## 1.1.2 n 和 nvm | ||
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通常我们使用稳定的 LTS 版本的 Node.js 即可,但有的情况下我们又想尝试一下新的特性,我们总不能来回安装不同版本的 Node.js 吧,这个时候我们就需要 [n](https://github.com/tj/n) 或者 [nvm](https://github.com/creationix/nvm) 了。n 和 nvm 是两个常用的 Node.js 版本管理工具,关于 n 和 nvm 的使用以及区别,[这篇文章](http://taobaofed.org/blog/2015/11/17/nvm-or-n/) 讲得特别详细,这里不再赘述。 | ||
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## 1.1.3 nrm | ||
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[nrm](https://github.com/Pana/nrm) 是一个管理 npm 源的工具。用过 ruby 和 gem 的同学会比较熟悉,通常我们会把 gem 源切到国内的淘宝镜像,这样在安装和更新一些包的时候比较快。nrm 同理,用来切换官方 npm 源和国内的 npm 源(如: [cnpm](http://cnpmjs.org/)),当然也可以用来切换官方 npm 源和公司私有 npm 源。 | ||
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全局安装 nrm: | ||
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``` | ||
npm i nrm -g | ||
``` | ||
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查看当前 nrm 内置的几个 npm 源的地址: | ||
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![](./img/1.1.4.png) | ||
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切换到 cnpm: | ||
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![](./img/1.1.5.png) | ||
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下一节:[1.2 MongoDB 的安装与使用](https://github.com/nswbmw/N-blog/blob/master/book/1.2%20MongoDB%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md) |
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## 1.2.1 安装与启动 MongoDB | ||
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- Windows 用户向导:https://docs.mongodb.com/manual/tutorial/install-mongodb-on-windows/ | ||
- Linux 用户向导:https://docs.mongodb.com/manual/administration/install-on-linux/ | ||
- Mac 用户向导:https://docs.mongodb.com/manual/tutorial/install-mongodb-on-os-x/ | ||
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## 1.2.2 Robomongo 和 Mongochef | ||
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#### Robomongo | ||
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[Robomongo](https://robomongo.org/) 是一个基于 Shell 的跨平台开源 MongoDB 可视化管理工具,支持 Windows、Linux 和 Mac,嵌入了 JavaScript 引擎和 MongoDB mongo,只要你会使用 mongo shell,你就会使用 Robomongo,它还提了供语法高亮、自动补全、差别视图等。 | ||
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[Robomongo 下载地址](https://robomongo.org/download) | ||
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下载并安装成功后点击左上角的 `Create` 创建一个连接,给该连接起个名字如: `localhost`,使用默认地址(localhost)和端口(27017)即可,点击 `Save` 保存。 | ||
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![](./img/1.2.1.png) | ||
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双击 `localhost` 连接到 MongoDB 并进入交互界面,尝试插入一条数据并查询出来,如下所示: | ||
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![](./img/1.2.2.png) | ||
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#### MongoChef | ||
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[MongoChef](http://3t.io/mongochef/) 是另一款强大的 MongoDB 可视化管理工具,支持 Windows、Linux 和 Mac。 | ||
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[MongoChef 下载地址](http://3t.io/mongochef/#mongochef-download-compare),我们选择左侧的非商业用途的免费版下载。 | ||
|
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![](./img/1.2.3.png) | ||
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安装成功后跟 Robomongo 一样,也需要创建一个新的连接的配置,成功后双击进入到 MongoChef 主页面,如下所示: | ||
|
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![](./img/1.2.4.png) | ||
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还可以使用 shell 模式: | ||
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||
![](./img/1.2.5.png) | ||
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> 小提示: MongoChef 相较于 Robomongo 更强大一些,但 Robomongo 比较轻量也能满足大部分的常规需求,所以哪一个适合自己还需读者自行尝试。 | ||
上一节:[1.1 Node.js 的安装与使用](https://github.com/nswbmw/N-blog/blob/master/book/1.1%20Node.js%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md) | ||
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下一节:[2.1 require](https://github.com/nswbmw/N-blog/blob/master/book/2.1%20require.md) |
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require 用来加载一个文件的代码,关于 require 的机制这里不展开讲解,请仔细阅读 [官方文档](https://nodejs.org/api/modules.html)。 | ||
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简单概括以下几点: | ||
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- require 可加载 .js、.json 和 .node 后缀的文件 | ||
- require 的过程是同步的,所以这样是错误的: | ||
``` | ||
setTimeout(() => { | ||
module.exports = { a: 'hello' }; | ||
}, 0); | ||
``` | ||
require 这个文件得到的是空对象 `{}` | ||
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- require 目录的机制是: | ||
- 如果目录下有 package.json 并指定了 main 字段,则用之 | ||
- 如果不存在 package.json,则依次尝试加载目录下的 index.js 和 index.node | ||
- require 过的文件会加载到缓存,所以多次 require 同一个文件(模块)不会重复加载 | ||
- 判断是否是程序的入口文件有两种方式: | ||
- require.main === module(推荐) | ||
- module.parent === null | ||
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#### 循环引用 | ||
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循环引用(或循环依赖)简单点来说就是 a 文件 require 了 b 文件,然后 b 文件又反过来 require 了 a 文件。我们用 a->b 代表 b require 了 a。 | ||
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简单的情况: | ||
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``` | ||
a->b | ||
b->a | ||
``` | ||
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复杂点的情况: | ||
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``` | ||
a->b | ||
b->c | ||
c->a | ||
``` | ||
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循环引用并不会报错,导致的结果是 require 的结果是空对象 `{}`,原因是 b require 了 a,a 又去 require 了 b,此时 b 还没初始化好,所以只能拿到初始值 `{}`。当产生循环引用时一般有两种方法解决: | ||
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1. 通过分离共用的代码到另一个文件解决,如上面简单的情况,可拆出共用的代码到 c 中,如下: | ||
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``` | ||
c->a | ||
c->b | ||
``` | ||
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2. 不在最外层 require,在用到的地方 require,通常在函数的内部 | ||
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总的来说,循环依赖的陷阱并不大容易出现,但一旦出现了,对于新手来说还真不好定位。它的存在给我们提了个醒,要时刻注意你项目的依赖关系不要过于复杂,哪天你发现一个你明明已经 exports 了的方法报 `undefined is not a function`,我们就该提醒一下自己:哦,也许是它来了。 | ||
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官方示例: [https://nodejs.org/api/modules.html#modules_cycles](https://nodejs.org/api/modules.html#modules_cycles) | ||
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上一节:[1.2 MongoDB 的安装与使用](https://github.com/nswbmw/N-blog/blob/master/book/1.2%20MongoDB%20%E7%9A%84%E5%AE%89%E8%A3%85%E4%B8%8E%E4%BD%BF%E7%94%A8.md) | ||
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下一节:[2.2 exports 和 module.exports](https://github.com/nswbmw/N-blog/blob/master/book/2.2%20exports%20%E5%92%8C%20module.exports.md) |
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