Node.js 웹 서버 구축 및 CORS 문제 해결

Node.js의 HTTP 모듈을 사용한 간단한 웹서버 Node.js의 http모듈을 사용하면 간단한 웹서버를 직접 구축할 수 있다. 하지만 이 방식은 기능이 제한적이어서 복잡한 애플리케이션을 개발하는 데는 한계가 있다. Node.js의 HTTP 모듈을 사용한 간단한 웹서버 Node.js의 http모듈을 사용하면 간단한 웹서버를 직접 구축할 수 있다. 하지만 이 방식은 기능이 제한적이어서 복잡한 애플리케이션을 개발하는 데는 한계가 있다.

import http from ‘http’; // HTTP 모듈 임포트 http.createServer((req, res) = > { // 응답 헤더 설정: 200 상태 코드와 HTML 문서로 응답 res。writeHead(200, {‘Content-Type’: ‘text/html; charset=utf-8’}); // 응답 내용 작성 res。write(‘<h1>환영합니다! 노드 서버 세상에 오신 것을···</h1>’);res.write (‘<p>반가워요^0^</p>’); // 응답 종료 res.end(‘<p>Hi</p>’);})listen(8080, () = { console.log (‘서버 서비스 중…’);};}); import http from ‘http’; // HTTP 모듈 임포트 http.createServer((req, res) = > { // 응답 헤더 설정: 200 상태 코드와 HTML 문서로 응답 res。writeHead(200, {‘Content-Type’: ‘text/html; charset=utf-8’}); // 응답 내용 작성 res。write(‘<h1>환영합니다! 노드 서버 세상에 오신 것을···</h1>’);res.write (‘<p>반가워요^0^</p>’); // 응답 종료 res.end(‘<p>Hi</p>’);})listen(8080, () = { console.log (‘서버 서비스 중…’);};});

Create an HTTP module impedance, using the HTTP module impedance of Node.js to create a server generation method. – This server sets the response header to implement the client’s request (res) and server to implement a simple server to implement the corresponding to the server.To overcome these limitations, more powerful and flexible tools to build a powerful web server to develop strong web server, which is easy to develop strong web servers and flexible tools.js environmentExExpress installation す

Install npm install express Install npm install express

You can also install the “nodemon” module for automatic restart during development. This makes it easier to reflect code changes under development. You can also install the “nodemon” module for automatic restart during development. This makes it easier to reflect code changes under development.

npm install –save-dev node Mon npm install –save-dev node mon

 

 

Express Application Generation – Generate an Express Application with the express() function. Set the port number in the environment variable setting -app.set(‘port’, process.env.PORT|3000). Use the Routing Settings-app.get() method to process various URL paths and HTTP GET requests. – Files can be transferred or JSON data can be responded to. Server Start – Start the server with app.listen(). – The port number is used with the configured value. Express AdvantagesSimple routing: Routing can be easily configured through HTTP methods (GET, POST, etc.) and URL paths. Middleware support—Easily add middleware to perform specific tasks before request and response processing. Flexible construction: Supports a variety of expansion modules and middleware to flexibly configure application structures. The same source policy, CORS problems and solutions CORS (Cross-Origin Resource Sharing), is a security constraint that occurs when a web browser requests resources from other sources. For example, attempting to access a server running on http://localhost:3000 with http://localhost:8080 might result in a CORS error. Express Application Generation – Generate an Express Application with the express() function. Set the port number in the environment variable setting -app.set(‘port’, process.env.PORT|3000). Use the Routing Settings-app.get() method to process various URL paths and HTTP GET requests. – Files can be transferred or JSON data can be responded to. Server Start – Start the server with app.listen(). – The port number is used with the configured value. Express AdvantagesSimple routing: Routing can be easily configured through HTTP methods (GET, POST, etc.) and URL paths. Middleware support—Easily add middleware to perform specific tasks before request and response processing. Flexible construction: Supports a variety of expansion modules and middleware to flexibly configure application structures. The same source policy, CORS problems and solutions CORS (Cross-Origin Resource Sharing), is a security constraint that occurs when a web browser requests resources from other sources. For example, attempting to access a server running on http://localhost:3000 with http://localhost:8080 might result in a CORS error.

Screen when connecting to http://localhost:3030 with various URLs. Screen when connecting to http://localhost:3030 with various URLs.

CORS policy blocked access to get from origin ‘http://localhost:8080’ with error ‘http://localhost:3000/user/winter’: The requested resource does not have the ‘Access-Control-Allow-Origin’ header. If the opaque response meets your needs, set the mode of the request to ‘no-cors’ and retrieve the resource with CORS disabled. CORS policy blocked access to get from origin ‘http://localhost:8080’ with error ‘http://localhost:3000/user/winter’: The requested resource does not have the ‘Access-Control-Allow-Origin’ header. If the opaque response meets your needs, set the mode of the request to ‘no-cors’ and retrieve the resource with CORS disabled.

How to troubleshoot CORS problems Express can use the cors package to troubleshoot CORS problems. The cors package helps you easily add CORS settings to the server. 1. CORS Package Installation How to troubleshoot CORS problems Express can use the cors package to troubleshoot CORS problems. The cors package helps you easily add CORS settings to the server. 1. CORS Package Installation

npm Installation Cols npm Install Cols

2. Add CORS settings to the Express application and add CORS middleware to the Express application as follows. 2. Add CORS settings to the Express application and add CORS middleware to the Express application as follows.

import express from ‘express’;import path from ‘path’; { fileURLToPath } from ‘url’; // CORS 해결을 위한 패키지 임포트 const app = express (); // Express 애플리케이션 생성// CORS 미들웨어 사용 app.use(cors()); // 모든 출처의 요청을 허용// ··· import express from ‘express’;import path from ‘path’; { fileURLToPath } from ‘url’; // CORS 해결을 위한 패키지 임포트 const app = express (); // Express 애플리케이션 생성// CORS 미들웨어 사용 app.use(cors()); // 모든 출처의 요청을 허용// ···

 

위의 코드에서 app.use(cors());를 추가하면 모든 소스의 요청을 허용하게 됩니다. 이를 통해 CORS 문제를 해결할 수 있습니다. 위의 코드에서 app.use(cors());를 추가하면 모든 소스의 요청을 허용하게 됩니다. 이를 통해 CORS 문제를 해결할 수 있습니다.