koa 练习
const koa = require('koa') const path = require('path') const fs = require('fs') const mimes = require('./util/mimes.js') var app = new koa() app.use(async ctx => { let fullStaticPath = path.join(__dirname, './static') let _content = await content(ctx, fullStaticPath) let _mime = praseMime(ctx.url) if (_mime) { ctx.type = _mime } ctx.body = _content }) app.listen(3000) console.log('[demo] static-server is starting at port 3000') /** * 获取静态资源内容 * * @param {object} ctx koa上下文 * @param {string} fullStaticPath 静态资源目录在本地的绝对路径 * @return {string} 请求获取到的本地内容 */ async function content(ctx, fullStaticPath) { let reqPath = path.join(fullStaticPath, ctx.url) console.log('reqPath:', reqPath) let exist = fs.existsSync(reqPath) console.log('exist:', exist) let content = '' if (!exist) { content = '404 Not Found' } else { let stat = fs.statSync(reqPath) console.log('stat:', stat) if (stat.isDirectory()) { let contentList = fs.readdirSync(reqPath) console.log('contentList:', contentList) let html = `<ul>` for (let [index, item] of contentList.entries()) { html = `${html}<li><a href="${ctx.url === '/' ? '' : ctx.url}/${item}">${item}</a>` } content = `${html}</ul>` } else { content = await fs.readFileSync(reqPath, 'binary') } } console.log('content:', content) return content } /** * 解析资源类型 * * @param {string} url ctx.url */ function praseMime(url) { let extName = path.extname(url) console.log('extName:', extName) extName = extName ? extName.slice(1) : 'unknown' return mimes[extName] }
let mimes = { 'css': 'text/css', 'less': 'text/css', 'gif': 'image/gif', 'html': 'text/html', 'ico': 'image/x-icon', 'jpeg': 'image/jpeg', 'jpg': 'image/jpeg', 'js': 'text/javascript', 'json': 'application/json', 'pdf': 'application/pdf', 'png': 'image/png', 'svg': 'image/svg+xml', 'swf': 'application/x-shockwave-flash', 'tiff': 'image/tiff', 'txt': 'text/plain', 'wav': 'audio/x-wav', 'wma': 'audio/x-ms-wma', 'wmv': 'video/x-ms-wmv', 'xml': 'text/xml' } module.exports = mimes
实现静态资源服务器,熟悉nodejs文件及目录的读写以及koa基础
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