How do I reuse a POST request and overwrites its payload? - go

Question

I have use case where a Go Client with a file-watcher listens to changes in a file and sends these changes to a Go server. If the Client can't reach the server during the POST requests with the payload of the file changes, the Client will keep trying every 3 seconds to send the request until err := http.NewRequest() dosen't return a non-nil err
But If the Client is currently trying every 3 seconds to send a POST request but at the same time a new change occurs to the file under file-watch, I want the current POST requests's payload to be overwritten by the new payload(new changes from the file)
How Do I archive this best?
Client code for sending an HTTP requests
func makeRequest(method string, body io.Reader) (*http.Response, error) {
client := &http.Client{}
request, err := http.NewRequest(.., .., ..)
if err != nil {
log.Println("Error: Couldn't make a new Request:", err)
return nil, err
}
response, err := client.Do(request)
if err != nil {
log.Printf("Error: Couldn't execute %s request:%s", method, err)
}
return response, err
}
The function that retries until err !=nil
func autoRetry(f func() error) {
if err := backoff.Retry(f, getBackOff()); err != nil {
log.Println("Error: Couldn't execute exponential backOff retries: ", err)
}
}
autoRetry() is just a function which takes a function and uses ExponentialBackOff to calculate the amount of tries until err !=nil
The call to the method doing the POST request with retries
func postTodo() {
autoRetry(func() error {
r, err := makeRequest("POST", getFileData())
if err != nil {
return err
}
if r.StatusCode != 200 {
return errors.New("Error:" + r.Status)
}
return nil
})
}