Freeswitch - How to create registrant in realtime without XML files

app.js

require('dotenv').config();
var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');

app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: true }));
app.use(cookieParser());

const users = {
  '1000': { password: 'secret1000', context: 'default' },
  '1001': { password: 'secret1001', context: 'default' },
};

app.all('/fs_directory', (req, res) => {
  console.log('POST Data:', req.body);

  const body = req.body;
  const section = Array.isArray(body.section) ? body.section[0] : body.section;
  const key_name = body.key_name;
  const key_value = body.key_value;
  const action = body.action;

  if (section !== 'directory') {
    return res.status(200).type('text/xml').send(notFoundXml());
  }

  res.type('text/xml');

  // sip_auth request — FreeSWITCH sends user= and domain= directly
  if (action === 'sip_auth' || body.key === 'id') {
    const username = body.user || body.sip_auth_username;
    const domain = body.domain || body.sip_auth_realm;
    const user = users[username];

    if (!user) {
      console.log(`User not found: ${username}`);
      return res.status(200).send(notFoundXml());
    }

    console.log(`sip_auth: returning XML for user ${username}@${domain}`);
    return res.status(200).send(userXml(username, user, domain));
  }

  // domain-level lookup
  if (key_name === 'name') {
    return res.status(200).send(domainXml(key_value));
  }

  // explicit user lookup by id
  if (key_name === 'id') {
    const username = key_value;
    const domain = body.domain || key_value;
    const user = users[username];

    if (!user) {
      console.log(`User not found: ${username}`);
      return res.status(200).send(notFoundXml());
    }

    console.log(`id lookup: returning XML for user ${username}@${domain}`);
    return res.status(200).send(userXml(username, user, domain));
  }

  return res.status(200).send(notFoundXml());
});

function userXml(username, { password, context }, domain) {
  return `<?xml version="1.0" encoding="UTF-8"?>
<document type="freeswitch/xml">
  <section name="directory">
    <domain name="${domain}">
      <user id="${username}">
        <params>
          <param name="password" value="${password}"/>
          <param name="vm-password" value="${password}"/>
        </params>
        <variables>
          <variable name="toll_allow" value="domestic,international,local"/>
          <variable name="accountcode" value="${username}"/>
          <variable name="user_context" value="${context}"/>
          <variable name="effective_caller_id_name" value="Extension ${username}"/>
          <variable name="effective_caller_id_number" value="${username}"/>
          <variable name="outbound_caller_id_name" value="\${outbound_caller_name}"/>
          <variable name="outbound_caller_id_number" value="\${outbound_caller_id}"/>
        </variables>
      </user>
    </domain>
  </section>
</document>`;
}

function domainXml(domain) {
  const dialString = '{^^:sip_invite_domain=' + domain + ':presence_id={dialed_user}@' + domain + '}${sofia_contact(*/${dialed_user}@' + domain + ')},${verto_contact(${dialed_user}@' + domain + ')}';
  const xml = `<?xml version="1.0" encoding="UTF-8"?>
<document type="freeswitch/xml">
  <section name="directory">
    <domain name="${domain}">
      <params>
        <param name="dial-string" value="${dialString}"/>
      </params>
      <variables>
        <variable name="record_stereo" value="true"/>
        <variable name="default_gateway" value="\${default_provider}"/>
        <variable name="default_areacode" value="\${default_areacode}"/>
        <variable name="transfer_fallback_extension" value="operator"/>
      </variables>
    </domain>
  </section>
</document>`;

  console.log('domainXml response:\n', xml);  // <-- add this
  return xml;
}

function notFoundXml() {
  return `<?xml version="1.0" encoding="UTF-8"?>
<document type="freeswitch/xml">
  <section name="directory">
  </section>
</document>`;
}

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  next(createError(404));
});

// error handler
app.use(function(err, req, res, next) {
  console.error('Error:', err.message);  // add this
  res.status(403).send("Forbidden");
});

module.exports = app;