nodejs中间件详解

1.logger

做用:用来输出用户请求日志

参数:options或者format字符串

• format:参考下面的tokens
• stream:输出流，默认是stdout
• buffer:缓冲时间，默认是1000ms
• immediate:马上打印日志

tokens: format格式

• :req[header] ex: :req[Accept]
• :res[header] ex: :res[Content-Length]
• :http-version
• :response-time
• :remote-addr
• :date
• :method
• :url
• :referrer
• :user-agent
• :status

Formats:缩写

default ‘:remote-addr – – [:date] “:method :url HTTP/:http-version” :status :res[content-length] “:referrer” “:user-agent”‘
short ‘:remote-addr – :method :url HTTP/:http-version :status :res[content-length] – :response-time ms’
tiny ‘:method :url :status :res[content-length] – :response-time ms’
dev concise output colored by response status for development use

例子：新建logger.js

var connect = require('connect');
var app = connect()
   .use(connect.logger())
   .use(function (req, res) {
       res.end('hello world\n');
   })
   .listen(3000);

connect.logger()

127.0.0.1 - - [Mon, 23 Sep 2013 05:14:18 GMT] "GET / HTTP/1.1" 200 - "-" "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKi
t/537.36 (KHTML, like Gecko) Chrome/28.0.1500.95 Safari/537.36"
127.0.0.1 - - [Mon, 23 Sep 2013 05:14:18 GMT] "GET /favicon.ico HTTP/1.1" 200 - "-" "Mozilla/5.0 (Windows NT 6.1; WOW64)
 AppleWebKit/537.36 (KHTML, like Gecko) Chrome/28.0.1500.95 Safari/537.36"

connect.logger(‘short’)

127.0.0.1 - GET / HTTP/1.1 200 - - 9 ms
127.0.0.1 - GET /favicon.ico HTTP/1.1 200 - - 1 ms

connect.logger(‘dev’)

GET / 200 5ms
GET /favicon.ico 200 1ms

connect.logger(function(tokens, req, res){ return ‘some format string’ })

some format string
some format string

因此在开发环境，咱们日志设置成dev就行了。