size.js

const fs = require('fs');
const express=require('express');
var mysql = require('mysql');
var jsonexport = require('jsonexport');
var Parser = require("fast-xml-parser");
var formidable = require('formidable');
const cors = require('cors');
const path = require("path") 
var bodyParser = require('body-parser');

var parse = require('csv-parse');
const csv = require('csv-parser')
var app = express();
app.set("views",path.join(__dirname,"views")) 
app.set("view engine","pug") 
app.use(bodyParser.json());                        
app.use(bodyParser.urlencoded({extended: true}));
app.use(express.static(path.join(__dirname, 'public')));
app.use(cors());
app.options('*', cors());

const db =mysql.createConnection({
  connectionLimit : 100,
  host: 'localhost',
  user :'root',
  password:'',
  database:'woo'
  });
      
  db.connect((err)=>{
  
  if(err){throw err;}
  console.log('connection established..'); }); 

//***********parsing xml data---headers exraction and insertion**** */
var upload_html = fs.readFileSync(".//views//upload.html");
app.get("/",function(req,res){ 
 res.writeHead(200);
res.write(upload_html);
  res.end();
      })
      
app.post('/', (req, res) => {
    var csvNewpath= ".//files/file.csv"; 
    let counter=0;
    const myData = [];

    var form = new formidable.IncomingForm();
    form.parse(req, function (err, fields, files) {
   //   var fileType = files.ext.type.split('/').pop();
   var oldpath = files.ext.path;



fs.readFile(oldpath, 'utf8', function(err, contents) {
  var options = {
    attributeNamePrefix : "",
    attrNodeName:'',
    textNodeName :false,
    ignoreAttributes : true,
    ignoreNameSpace : false,
    allowBooleanAttributes : false,
    parseNodeValue : true,
    parseAttributeValue : false,
    trimValues: true,
    cdataTagName: false,
    cdataPositionChar: "\\c",
    parseTrueNumberOnly: false,
    arrayMode: true, //"strict"
    stopNodes: '.'
    };
 // Intermediate obj
 var tObj = Parser.getTraversalObj(contents,options);
 var jsonObj = Parser.convertToJson(tObj,options);
   var results=[]   
   var key = Object.values(jsonObj);
    results.push(key);
    jsonexport(results,function(err, csv){
      if(err) return console.log(err);  
      
  fs.writeFile(csvNewpath, csv ,function(err, result) {
      if(err) 
      console.log('error', err);
      fs.ReadStream(csvNewpath,'utf8',{pretty:true})
              .pipe(
                  parse({
                      delimiter:','
                  })
              )
              .on("data", function (dataRow) {
                if(counter<50){
                  myData.push(dataRow);
                  
              ++counter;
                }
              }).on("end", function () {
                        
                res.render('xmlForm', { data: myData })
            }); 
  })
  })
   
              




fs.createReadStream('.//files/file.csv')
.pipe(csv({ mapHeaders: ({ header  }) => header.replace('.','_')}))
.on('headers', (headers) => {
   let i = 0;
  let text = headers;

for (i ; i<text.length ;i++){
      db.query('ALTER TABLE testtable ADD '+text[i]+' varchar(255)',(error, response) => {
       console.log(error || response);
   });
  }
  console.log(results); 
})  
})
})
})
 

//**************data columns insertion********** */

/* app.post('/column',(req,res)=>{
    let myData = [];
    fs.createReadStream('.\\files\\file.csv')
        .pipe(parse({ delimiter:',' }))
        .on("data", function (dataRow) {
            myData.push(dataRow);
        })
        .on("end", function () {
            myData.shift();
            const connection = mysql.createConnection({
    
                host: 'localhost',
                user :'root',
                password:'',
                database:'woo'    
        });

        // open the connection
        connection.connect((err) => {
            if(err)
            {
                console.log(err);
            }else{
                let sql = 'ALTER TABLE users DROP id';
                connection.query(sql,(error, response) => {
                    console.log(error || response);
                });
               
                let query = 'INSERT INTO users VALUES ?';
                connection.query(query, [myData], (error, response) => {
                    console.log(error || response);
                }); 
            }
        });
            });
           }); */
    
app.listen('3000',()=>{console.log('server started on port 3000');});