Hyperledger-study-35

하이퍼레져 앱 만들기 실습 35일차 - express 설치, Hello world 출력, express 언어로 변경

출처 : https://opentutorials.org/course/3370/21387

1. express 설치

    # npm install express --save
   

2. Hello world 출력

    const express = require('express')
    const app = express()
   
    app.get('/', (req, res) => res.send('Hello World!'))
   
    app.listen(3000, () => console.log('Example app listening on port 3000!'))
   

3. route, routing

    const express = require('express')
    const app = express()
   
    //route, routing
    // app.get('/', (req, res) => res.send('Hello World!'))
    app.get('/', function(req, res){
      return res.send('/')
    });
   
    app.get('/', function(req, res){
      return res.send('/page')
    });
   
    app.listen(3000, () => console.log('Example app listening on port 3000!'))
   

4. express 언어로 변경 - create, update, delete

main.js

    var express = require('express')
    var app = express()
    var fs = require('fs');
    var path = require('path');
    var qs = require('querystring');
    var sanitizeHtml = require('sanitize-html');
    var template = require('./lib/template.js');

    //route, routing
    //app.get('/', (req, res) => res.send('Hello World!'))
    app.get('/', function(request, response) { 
      fs.readdir('./data', function(error, filelist){
        var title = 'Welcome';
        var description = 'Hello, Node.js';
        var list = template.list(filelist);
        var html = template.HTML(title, list,
          `<h2>${title}</h2>${description}`,
          `<a href="/create">create</a>`
        ); 
        response.send(html);
      });
    });

    app.get('/page/:pageId', function(request, response) { 
      fs.readdir('./data', function(error, filelist){
        var filteredId = path.parse(request.params.pageId).base;
        fs.readFile(`data/${filteredId}`, 'utf8', function(err, description){
          var title = request.params.pageId;
          var sanitizedTitle = sanitizeHtml(title);
          var sanitizedDescription = sanitizeHtml(description, {
            allowedTags:['h1']
          });
          var list = template.list(filelist);
          var html = template.HTML(sanitizedTitle, list,
            `<h2>${sanitizedTitle}</h2>${sanitizedDescription}`,
            ` <a href="/create">create</a>
              <a href="/update/${sanitizedTitle}">update</a>
              <form action="/delete_process" method="post">
                <input type="hidden" name="id" value="${sanitizedTitle}">
                <input type="submit" value="delete">
              </form>`
          );
          response.send(html);
        });
      });
    });

    app.get('/create', function(request, response){
      fs.readdir('./data', function(error, filelist){
        var title = 'WEB - create';
        var list = template.list(filelist);
        var html = template.HTML(title, list, `
          <form action="/create_process" method="post">
            <p><input type="text" name="title" placeholder="title"></p>
            <p>
              <textarea name="description" placeholder="description"></textarea>
            </p>
            <p>
              <input type="submit">
            </p>
          </form>
        `, '');
        response.send(html);
      });
    });

    app.post('/create_process', function(request, response){
      var body = '';
      request.on('data', function(data){
          body = body + data;
      });
      request.on('end', function(){
          var post = qs.parse(body);
          var title = post.title;
          var description = post.description;
          fs.writeFile(`data/${title}`, description, 'utf8', function(err){
            response.redirect('/');
          })
      });
    });

    app.get('/update/:pageId', function(request, response){
      fs.readdir('./data', function(error, filelist){
        var filteredId = path.parse(request.params.pageId).base;
        fs.readFile(`data/${filteredId}`, 'utf8', function(err, description){
          var title = request.params.pageId
          var list = template.list(filelist);
          var html = template.HTML(title, list,
            `
            <form action="/update_process" method="post">
              <input type="hidden" name="id" value="${title}">
              <p><input type="text" name="title" placeholder="title" value="${title}"></p>
              <p>
                <textarea name="description" placeholder="description">${description}</textarea>
              </p>
              <p>
                <input type="submit">
              </p>
            </form>
            `,
            `<a href="/create">create</a> <a href="/update?id=${title}">update</a>`
          );
          response.send(html);
        });
      });
    });

    app.post('/update_process', function(request, response){
      var body = '';
          request.on('data', function(data){
              body = body + data;
          });
          request.on('end', function(){
              var post = qs.parse(body);
              var id = post.id;
              var title = post.title;
              var description = post.description;
              fs.rename(`data/${id}`, `data/${title}`, function(error){
                fs.writeFile(`data/${title}`, description, 'utf8', function(err){
                  response.writeHead(302, {Location: `/?id=${title}`});
                  response.end();
                })
              });
          });
    });

    app.post('/delete_process', function(request, response){
      var body = '';
      request.on('data', function(data){
        body = body + data;
      });
      request.on('end', function(){
        var post = qs.parse(body);
        var id = post.id;
        var filteredId = path.parse(id).base;
        fs.unlink(`data/${filteredId}`, function(error){
          response.redirect('/');
        })
      });
    });

    app.listen(3000, function() {
      console.log('Example app listening on port 3000!')
    });