node.js文件服务器

一个简单的node.js文件服务器

• 启动文件app.js

//加载所需要的模块
var http = require('http');

var processRequest = require('./server');

//创建服务，这里很机智的把对response和request的处理封装成一个匿名函数，传入createServer中
//也可以直接在里面写，但是看起来不是很整洁
var httpServer = http.createServer((req, res) => {
    processRequest(req, res);
});

var port = 8888;

//指定一个监听的接口
httpServer.listen(port, function() {
    console.log(`app is running at port:${port}`);
});

• http映射名

module.exports = {
    "css": "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",
    'txt': 'text/plain',
    'md': 'text/plain',
    '': 'text/plain',
};

• 核心服务类

var url = require('url');

var fs = require('fs');

var path = require('path');

var mime = require('./mime');

function processRequest(request, response) {


    //request里面切出标识符字符串
    var requestUrl = request.url;
    //url模块的parse方法 接受一个字符串，返回一个url对象,切出来路径
    var pathName = url.parse(requestUrl).pathname;

    //对路径解码，防止中文乱码
    var pathName = decodeURI(pathName);

    //解决301重定向问题，如果pathname没以/结尾，并且没有扩展名
    if (!pathName.endsWith('/') && path.extname(pathName) === '') {

        pathName += '/';
        var redirect = "http://" + request.headers.host + pathName;
        response.writeHead(301, {
            location: redirect
        });
        //response.end方法用来回应完成后关闭本次对话，也可以写入HTTP回应的具体内容。
        response.end();
    };

    //获取资源文件的绝对路径
    var filePath = path.resolve(__dirname + pathName);
    console.log(filePath);
    //获取对应文件的文档类型
    //我们通过path.extname来获取文件的后缀名。由于extname返回值包含”.”，所以通过slice方法来剔除掉”.”，
    //对于没有后缀名的文件，我们一律认为是unknown。
    var ext = path.extname(pathName);
    ext = ext ? ext.slice(1) : 'unknown';

    //未知的类型一律用"text/plain"类型
    var contentType = mime[ext] || "text/plain";

    fs.stat(filePath, (err, stats) => {
        if (err) {
            response.writeHead(404, { "content-type": "text/html" });
            response.end("
404 Not Found
");
        };
        //没出错 并且文件存在
        if (!err && stats.isFile()) {
            response.writeHead(200, { "content-type": contentType });
            //建立流对象，读文件
            var stream = fs.createReadStream(filePath);
            //错误处理
            stream.on('error', function() {
                response.writeHead(500, { "content-type": contentType });
                response.end("
500 Server Error
");
            });
            //读取文件
            stream.pipe(response,true);
        };
        //如果路径是目录
        if (!err && stats.isDirectory()) {
            var html = " ";
            //读取该路径下文件
            fs.readdir(filePath, (err, files) => {
                if (err) {
                    console.log("读取路径失败！");
                } else {
                    for (var file of files) {
                        if (file === "index.html") {
                            response.writeHead(200, { "content-type": "text/html" });
                            response.end(file);
                            break;
                        };
                        html += `
${file}
`;
                        console.log(html);
                    }
                    response.writeHead(200, { "content-type": "text/html" });
                    response.end(html);
                };
            });
        };
    });
};

module.exports = processRequest;