node.js

var PORT = 3000

var http = require('http')
var url = require('url')
var fs = require('fs')
var mime = require('./mime').types
var path = require('path')

var server = http.createServer(function (request, response) {
    var pathname = url.parse(request.url).pathname
    // add default pathname -- index.html
    if (pathname.charAt(pathname.length - 1) == '/') {
        //如果访问目录
        pathname += 'index.html' //指定为默认网页
    }

    var realPath = path.join('assets', pathname)
    var ext = path.extname(realPath)
    ext = ext ? ext.slice(1) : 'unknown'
    fs.exists(realPath, function (exists) {
        if (!exists) {
            response.writeHead(404, {
                'Content-Type': 'text/plain',
            })
            response.end()
        } else {
            fs.readFile(realPath, 'binary', function (err, file) {
                if (err) {
                    response.writeHead(500, {
                        'Content-Type': 'text/plain',
                    })
                    response.end()
                } else {
                    var contentType = mime[ext] || 'text/plain'
                    response.writeHead(200, {
                        'Content-Type': contentType,
                    })
                    response.write(file, 'binary')
                    response.end()
                }
            })
        }
    })
})

server.listen(PORT)
console.log('server running at port: ' + PORT + '.')