提交webserver文件

webServer.js

@@ -0,0 +1,204 @@
+const fs = require('fs');
+const url = require('url');
+const path = require('path');
+const http = require('http');
+const crypto = require('crypto');
+const xml2js = require('xml2js');
+const config = {};
+
+// 常见静态文件格式
+const mime = {
+    "html": "text/html",
+    "css": "text/css",
+    "js": "text/javascript",
+    "json": "application/json",
+    "gif": "image/gif",
+    "ico": "image/x-icon",
+    "jpeg": "image/jpeg",
+    "jpg": "image/jpeg",
+    "png": "image/png"
+}
+const app = {};
+app.routes = [];
+let _static = '.';
+// 命令集合
+const methods = ['get', 'post', 'put', 'delete', 'options', 'all', 'use'];
+// 实现路由池
+methods.forEach((method) => {
+    app[method] = (path, fn) => {
+        app.routes.push({method, path, fn});
+    }
+});
+
+// 使用generator函数实现惰性求值
+const lazy = function* (arr) {
+    yield* arr;
+}
+
+// 遍历路由池
+// routes 路由池
+// method 命令
+// path 请求路径
+const passRouter = (routes, method, path) => (req, res) => {
+    // 模式匹配
+    const replaceParams = (path) => new RegExp(`\^${path.replace(/:\w[^\/]+/g, '\\w[^\/]+')}\$`);
+    const lazyRoutes = lazy(routes);
+    (function next() {
+        // 当前遍历状态
+        const it = lazyRoutes.next().value;
+        if (!it) {
+            // 已经遍历了所有路由 停止遍历
+            res.end(`Cannot ${method} ${path}`);
+            return;
+        } else if (it.method === 'use' && (it.path === '/' || it.path === path || path.startsWith(it.path.concat('/')))) {
+            // 匹配到中间件
+            it.fn(req, res, next);
+        } else if ((it.method === method || it.method === 'all') && (it.path === path || it.path === "*")) {
+            // 匹配到路由
+            it.fn(req, res);
+        } else if (it.path.includes(':') && (it.method === method || it.method === 'all') && (replaceParams(it.path).test(path))) {
+            // 模式匹配
+            let index = 0;
+            const params2Array = it.path.split('/'); // 注册函数的path
+            const path2Array = path.split('/');// 请求路径的path
+            const params = {};
+            params2Array.forEach((path) => {
+                if (/\:/.test(path)) {
+                    // 如果是模式匹配的路径 就加入params对象中
+                    params[path.slice(1)] = path2Array[index];
+                }
+                index++
+            })
+            req.params = params;
+            it.fn(req, res);
+        } else if (it.method === 'get' && it.path.includes(req.url)) {
+            // 若允许访问的目录的子目录未允许访问
+            res.writeHead(403, {'content-type': 'text/plain;charset=utf-8'});
+            res.end(`暂未有访问权限`);
+            return;
+        } else {
+            // 继续匹配
+            next();
+        }
+    })()
+}
+
+// 处理静态文件函数
+// res response对象
+// pathName 静态文件相对路径
+// ext 静态文件后缀
+function handleStatic(res, pathName, ext) {
+    fs.exists(pathName, (exists) => {
+        if (!exists) {
+            res.writeHead(404, {'Content-Type': 'text/plain'});
+            res.write('The request url ' + pathName + ' was not found on this server');
+            res.end();
+        } else {
+            fs.readFile(pathName, (err, file) => {
+                if (err) {
+                    res.writeHead(500, {'Cotent-Type': 'text/plain'});
+                    res.end(err);
+                } else {
+                    // etag用于检验文件是否有变动
+                    const etag = crypto.createHash('md5').update(file).digest('hex'); // md5算法
+                    if (res.ifNoneMatch === etag) {
+                        res.writeHead(304);
+                        res.end()
+                    } else {
+                        const ContentType = mime[ext] || 'text/plain';
+                        res.setHeader('Etag', etag);
+                        res.writeHead(200, {'Cotent-Type': ContentType});
+                        res.write(file);
+                        res.end();
+                    }
+                }
+            })
+        }
+    })
+}
+
+// 目录浏览
+// dir 需要提供目录浏览功能的目录
+// dirname 本地路径 即__dirname 
+// bool 子目录是否提供浏览功能
+app.dir = function (_dir, dirname, bool) {
+    app.get(_dir, (req, res) => {
+        let html = "<head><meta charset='utf-8'></head>";
+        try {
+            // 用户访问目录
+            let files = fs.readdirSync(dirname + _dir);
+            let fileName = null;
+            for (let i in files) {
+                if (path.extname(files[i]) === "" && bool === true) {
+                    app.dir(_dir + '/' + files[i], dirname, bool)
+                }
+                fileName = files[i];
+                html += "<div><a  href='" +_dir + '/' + fileName + "'>" + fileName + "</a></div>";
+            }
+        } catch (e) {
+            html += '<h1>您访问的目录不存在</h1>';
+        }
+        res.writeHead(200, {'content-type': 'text/html'});
+        res.end(html);
+    })
+}
+
+// 启动服务
+app.listen = (port, host, callback) => {
+    http.createServer((req, res) => {
+        // 获取请求的方法
+        const method = req.method.toLowerCase()
+        // 解析url
+        const urlObj = url.parse(req.url, true)
+        // 获取path部分
+        const pathName = urlObj.pathname
+        // 获取后缀
+        const ext = path.extname(pathName).slice(1);
+        // 若有后缀 则是静态文件
+        if (ext) {
+            // if-none-match 判断缓存是否可用
+            res.ifNoneMatch = req.headers['if-none-match'];
+            handleStatic(res, _static + pathName, ext)
+        } else {
+            // 遍历路由池
+            passRouter(app.routes, method, pathName)(req, res)
+        }
+    }).listen(port, host, ()=>{
+        console.log(`server start at http://${host}:${port}`)
+    });
+};
+
+// 解析web.config
+app.resolve = () => {
+    let parser = new xml2js.Parser({explicitArray : false});
+    fs.readFile('./web.config', (err, file) => {
+        parser.parseString(file, (err, result) => {
+            for(let i in result.webconfig) {
+                config[i] = result.webconfig[i]
+            }
+            app.doDir();
+        })
+    })
+}
+
+// 目录配置字符串解析并调用dir函数
+app.doDir = () => {
+    for(let i of config.resolveDir.dir) {
+        if (i.indexOf("[") === 0) {
+            i = i.substring(1, i.length - 1);
+        }
+        i = i.split(',');
+        app.dir(i[0], __dirname, i[1]);
+    }
+    app.listen(config.port, config.host);
+}
+
+app.use('/blog', (req, res, next) => {
+    console.log('%s %s', req.method, req.url);
+    next()
+})
+app.get('/blog/:id', (req, res, next) => {
+    res.end('hello ' + req.params.id)
+})
+
+app.resolve();