Example of sending command to rAthena database.

app.js

const axios = require('axios');
const qs = require('qs');

const payload = qs.stringify({
 'command': '@deathnote plan3'  // example command
});
const config = {
  method: 'post',
  url: 'http://128.199.234.106/?module=webcommands',
  headers: { 
    'Connection': 'keep-alive', 
    'Pragma': 'no-cache', 
    'Cache-Control': 'no-cache', 
    'Upgrade-Insecure-Requests': '1', 
    'Origin': 'http://128.199.234.106', 
    'Content-Type': 'application/x-www-form-urlencoded', 
    'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.116 Safari/537.36', 
    'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9', 
    'Referer': 'http://128.199.234.106/?module=account&action=login&return_url=%2F%3Fmodule%3Dwebcommands', 
    'Accept-Language': 'en,th-TH;q=0.9,th;q=0.8', 
    'Cookie': 'fluxSessionData=pppt6pm239fl6ofsviime4so07; fluxSessionData=2k79opjjk55um0mp76fuaj4eit'
  },
  data: payload
};

axios(config)
.then(function (response) {
  console.log(JSON.stringify(response.data));
})
.catch(function (error) {
  console.log(error);
});

Get Cookie by login account on fluxCP site.