随堂练习：写一个基于koa的静态http模块并发布

重点在于理解koa中间件，扩展koa用法（不只是web框架，它还是Node.js模块，它可以做更多），并复习巩固上一节学的Node.js模块写法

练习koa用法，集成以下中间件

  1.     "koa": "^2.0.0",
  2.     "koa-compress": "^2.0.0",
  3.     "koa-conditional-get": "^2.0.0",
  4.     "koa-etag": "^3.0.0",
  5.     "koa-favicon": "^2.0.0",
  6.     "koa-static": "^3.0.0",

app.js

  1. var serve = require('koa-static');
  2. var Koa = require('koa');
  3. var app = new Koa();
  5. var favicon = require('koa-favicon');
  6. var compress = require('koa-compress')
  7. var conditional = require('koa-conditional-get');
  8. var etag = require('koa-etag');
  10. app.use(compress({
  11.   filter: function (content_type) {
  12.     return /text/i.test(content_type)
  13.   },
  14.   threshold: 2048,
  15.   flush: require('zlib').Z_SYNC_FLUSH
  16. }))
  19. app.use(favicon(__dirname + '/public/favicon.ico'));
  21. // etag works together with conditional-get
  22. app.use(conditional());
  23. app.use(etag());
  26. // or use absolute paths
  27. app.use(serve(__dirname + '/dist'));
  29. app.listen(9090);
  31. console.log('listening on port 9090');

将上面代码改成bin模块并发布

static http server模块核心是koa-static模块

  1. // or use absolute paths
  2. app.use(serve(__dirname + '/dist'));

这里的目录即要作为static http server的目录，也就是我们需要动态的把它通过命令行配置

假设模块名称为stuq-koa-static-server

  1. $ npm i -g stuq-koa-static-server

通过内置命令`stuq-koa-static-server启动服务，

  1. $ stuq-koa-static-server .

如果没有指定目录，即当前目录

  1. $ stuq-koa-static-server

知识点

  • 获取当前目录
  • 命令行参数解析，推荐commander

更多

参考http-server模块，增加更多cli配置项

  1. $ http-server -h
  2. usage: http-server [path] [options]
  4. options:
  5.   -p           Port to use [8080]
  6.   -a           Address to use [0.0.0.0]
  7.   -d           Show directory listings [true]
  8.   -i           Display autoIndex [true]
  9.   -e --ext     Default file extension if none supplied [none]
  10.   -s --silent  Suppress log messages from output
  11.   --cors[=headers]   Enable CORS via the "Access-Control-Allow-Origin" header
  12.                      Optionally provide CORS headers list separated by commas
  13.   -o [path]    Open browser window after starting the server
  14.   -c           Cache time (max-age) in seconds [3600], e.g. -c10 for 10 seconds.
  15.                To disable caching, use -c-1.
  16.   -U --utc     Use UTC time format in log messages.
  18.   -P --proxy   Fallback proxy if the request cannot be resolved. e.g.: http://someurl.com
  20.   -S --ssl     Enable https.
  21.   -C --cert    Path to ssl cert file (default: cert.pem).
  22.   -K --key     Path to ssl key file (default: key.pem).
  24.   -r --robots  Respond to /robots.txt [User-agent: *\nDisallow: /]
  25.   -h --help    Print this list and exit.