Google Apps Script - send spreadsheet changes to an external API

code.js

// provided `onEdit` trigger cannot use `UrlFetchApp.fetch`.
// create a custom-named function, then add it as a new trigger in "Edit" > "Current Project Triggers"
// with events "From spreadsheet" > "On edit"
function customOnEdit(e) {
  const range = e.range;
  const row = range.getRow();
  const sheet = e.source.getActiveSheet();
  
  const data = {
    vendor: sheet.getRange(row, 1).getValue(),
    sku: sheet.getRange(row, 2).getValue(),
    title: sheet.getRange(row, 3).getValue(),
    cost: sheet.getRange(row, 4).getValue()
  };
  Logger.log('data: ' + JSON.stringify(data));
  
  const keys = Object.keys(data);
  for (var i = 0; i < keys.length; i++) {
    var key = keys[i];
    if (data[key].length === 0) {
      Logger.log(key + ' contains no data, aborting.');
      return;
    }
  }
  
  Logger.log('All values in place, sending.');
  send(data);
}

function send(data) {
  // Key-value properties can be added under "File" > "Project properties" > "Script properties"
  const scriptProperties = PropertiesService.getScriptProperties();
  const baseURL = scriptProperties.getProperty('baseURL');
  // const baseURL = 'https://xxxxxxx.ngrok.io';  // for local testing
  
  const authData = {
    'email': scriptProperties.getProperty('email'),
    'password': scriptProperties.getProperty('password')
  };
  
  const authOpts = {
    'method': 'post',
    'contentType': 'application/json',
    'payload': JSON.stringify(authData)
  };

  const authResp = UrlFetchApp.fetch(baseURL + '/api/login', authOpts);  
  
  const authorization = authResp.getHeaders()["Authorization"];

  const options = {
    'method': 'post',
    'contentType': 'application/json',
    'payload': JSON.stringify(data),
    'headers': {
      'Authorization': authorization
    }
  };
  
  const response = UrlFetchApp.fetch(baseURL + '/admin_api/vendor_products', options);
  Logger.log(JSON.stringify(response));
}