Node.js web module

Node.js is a platform built on the Chrome JavaScript runtime.

Node.js is an event-driven I/O server-side JavaScript environment based on Google's V8 engine. The V8 engine executes Javascript very quickly and has very good performance.

Node.js web module syntax

Web server generally refers to a website server, which refers to a program that resides on a certain type of computer on the Internet. The basic function of a Web server is to provide Web information browsing services. It only needs to support the HTTP protocol, HTML document format and URL, and cooperate with the client's web browser.

Most web servers support server-side scripting languages ​​(php, python, ruby), etc., and obtain data from the database through scripting languages ​​and return the results to the client browser.

Node.js web module example

var http = require('http');
var fs = require('fs');
var url = require('url'); 
 
// 创建服务器http.createServer( function (request, response) {  
   // 解析请求，包括文件名
   var pathname = url.parse(request.url).pathname;   
   // 输出请求的文件名
   console.log("Request for " + pathname + " received.");   
   // 从文件系统中读取请求的文件内容
   fs.readFile(pathname.substr(1), function (err, data) {
      if (err) {
         console.log(err);         // HTTP 状态码: 404 : NOT FOUND
         // Content Type: text/plain
         response.writeHead(404, {'Content-Type': 'text/html'});      }else{             
         // HTTP 状态码: 200 : OK
         // Content Type: text/plain
         response.writeHead(200, {'Content-Type': 'text/html'});    
         
         // 响应文件内容
         response.write(data.toString());        
      }
      //  发送响应数据
      response.end();   });   
}).listen(8080); 
// 控制台会输出以下信息console.log('Server running at http://127.0.0.1:8080/');