acccess request body in success callback + axios code example
Example 1: axios library
<script src="https://cdn.jsdelivr.net/npm/axios/dist/axios.min.js"></script>
Example 2: axios put
const res = await axios.put('https://httpbin.org/put', { hello: 'world' });
res.data.headers['Content-Type']; // application/json;charset=utf-8