The request message was already sent. cannot send the same request message multiple times.

Error: the request message was already sent. cannot send the same request message multiple times.

Explanation:

When making requests to a server using HTTP, you can only send a single request message per connection. Once a request message has been sent, you cannot send the same request message again without closing the connection and opening a new one.

This error typically occurs when you attempt to send the same request multiple times using the same connection without properly closing it in between. It’s important to note that each request must be unique and should not be repeated unless you open a new connection.

Example:

Let’s consider a simple example of making an HTTP request using JavaScript:

// Create a new XMLHttpRequest object
var xhr = new XMLHttpRequest();

// Open a GET request to a URL
xhr.open('GET', 'https://example.com/api/data', true);

// Send the request
xhr.send();

// Attempt to send the same request again
xhr.send();  // This will cause an error

In the above example, calling xhr.send() multiple times will result in the mentioned error. To avoid this, you can close the previous connection or create a new instance of the XMLHttpRequest object before sending a new request.