How to correctly modify a fetch request for secure transmission of sensitive data?

To securely transmit sensitive data via fetch requests, it is important to consider several aspects:

1. Use HTTPS — to ensure data is transmitted over a secure channel.
2. Do not transmit sensitive data in the URL (e.g., in query parameters), as URLs can be logged and visible.
3. Send data in the request body, for example, in JSON format.
4. Use headers to transmit authorization tokens, such as Authorization: Bearer <token>.
5. Handle CORS and CSRF — to prevent attacks.

Example of a secure fetch request with token and data in the body:

fetch('https://api.example.com/secure-data', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
    'Authorization': 'Bearer your_access_token'
  },
  body: JSON.stringify({ sensitiveData: 'value' })
})
.then(response => response.json())
.then(data => console.log(data))
.catch(error => console.error('Error:', error));

Thus, avoid transmitting secrets in the URL, always use HTTPS, and send data in the request body with appropriate headers.