src/app.js

const http = require('http')
const path = require('path')
const url = require('url')
const fs = require('fs')
let chalk = require('chalk');
process.env.DEBUG = 'static:*';
let debug = require('debug')('static:app');//每个debug实例都有一个名字，是否在控制台打印取决于环境变量中DEBUG的值是否等于static:app
const mime = require('mime');
const {promisify} = require('util')
let handlebars = require('handlebars');

const config = require('./config')
const stat = promisify(fs.stat)
const readDir = promisify(fs.readdir)
//获取编译模板
function getTemplet() {
    let tmpl = fs.readFileSync(path.resolve(__dirname, 'template', 'list.html'), 'utf8');
    return handlebars.compile(tmpl);
}
class Server {
    constructor(argv) {
        this.config = Object.assign({}, config, argv);
        this.list = getTemplet();
    }
    //启动服务
    start() {
        let server = http.createServer();
        server.on('request', this.request.bind(this))
        server.listen(this.config.port);
        let url=`http://${this.config.host}:${this.config.port}`;
        debug(`静态服务启动成功${chalk.green(url)}`);
    }
    async request(req, res) {//服务监听函数
        let pathName = url.parse(req.url).path;
        let filePath = path.join(this.config.root, pathName);
        if (filePath.indexOf('favicon.ico') > 0) {
            this.sendError(req, res, 'not found');
            return
        }
        try {//在静态服务文件夹存在访问的路径内容
            let statObj = await stat(filePath);
            if (statObj.isDirectory()) {
                let directories = await readDir(filePath);
                let files = directories.map(file => {
                    return {
                        filename: file,
                        url: path.join(pathName, file)
                    }
                });
                let htmls = this.list({
                    title: pathName,
                    files
                });
                res.setHeader('Content-Type', 'text/html');
                res.end(htmls);
            } else {
                this.sendContent(req, res, filePath, statObj);
            }
        } catch (err) {//静态服务器不存在访问内容
            this.sendError(req, res, err);
        }
    }
    sendContent(req, res, filePath, statObj) {//向客户端响应内容
        let fileType = mime.getType(filePath);
        res.setHeader('Content-Type', `${fileType};charset=UTF-8`);
        let rs = this.getStream(filePath);//获取文件的可读流
        rs.pipe(res);
    }
    getStream(filePath) {//返回一个可读流
        return fs.createReadStream(filePath);
    }
    sendError(req, res, err) {//发送错误
        res.statusCode = 500;
        res.end(`${err.toString()}`)
    }
}
module.exports = Server;