added change in user_id posting to server

server.js

@@ -4,6 +4,8 @@ var multer = require('multer')
 var cors = require('cors');
 var bodyParser = require("body-parser");
 var https = require('https')
+var csv = require('csv');
+const { parse } = require("csv-parse");
 const util = require('util');
 const fs = require('fs');
 
@@ -121,7 +123,9 @@ app.post('/upload', function(req, res, next) {
 
 const converter = require('json-2-csv');
 
+
 app.post('/csv', (req, res, next) => {
+    let _res = "";
     const csv = req;
     userData = req.body;
 
@@ -129,12 +133,44 @@ app.post('/csv', (req, res, next) => {
         if (err) {
             throw err;
         }
+
+        let _userData = JSON.parse(userData);
+        _userEmail = _userData.mailadress;
+        //check for record alredy exist
+        try {
+            const path = '/var/www/html/appexe/natnats/23/bin/mobileweb2/resources/database/user_record.csv';
+            if (fs.existsSync(path)) {
+                fs.createReadStream(path)
+                .pipe(parse({ delimiter: ",", from_line: 1 }))
+                .on("data", function (row) {
+                    for(r in row){
+                        if(r[0] === _userEmail){
+                            _res = r[2];
+                            break;
+                        }
+                    }
+
+                    if(_res === ""){
+                        fs.appendFile(path, csv, function (err) {
+                            if (err) throw err;
+                            console.log('The "data to append" was appended to file!');
+                        });
+                        _res = 'OK';
+                        res.send(_res);
+                    }
+
+                });
+            }
+          } catch(err) {
+            console.error(err)
+          }
+
         writetoFile(csv);
         // print CSV string
         console.log(csv);
     });
 
-    res.send("OK");
+    res.send(_res);
 });
 
 function writetoFile(csv) {
@@ -147,7 +183,6 @@ function writetoFile(csv) {
 }
 
 app.listen(8000, function() {
-
     console.log('App running on port 8000');
 
 });