1. method: 'POST', // *GET, POST, PUT, DELETE, etc.
2. mode: 'cors', // no-cors, *cors, same-origin
3. cache: 'no-cache', // *default, no-cache, reload, force-cache, only-if-cached
4. credentials: 'same-origin', // include, *same-origin, omit
5. headers: {
'Content-Type': 'application/json'
// 'Content-Type': 'application/x-www-form-urlencoded',
},
7. redirect: 'follow', // manual, *follow, error
8. referrerPolicy: 'no-referrer', // no-referrer, *client
9. body: JSON.stringify(data) // body data type must match "Content-Type" header