Retry on failure

It's always good to give some more chances to the same action, this can easily be achieved by wrapping the request calls :

on_response handler

We can use the indirection offered by std::function, so that the request and the on_response handler can respectively refers each other.

 
  auto retries_count = 3;
  std::function<void(xxhr::Response&&)> retry_on_fail;
 

define the request

  auto do_request = [&]() { 
    GET( 
      "http://httpbin.org/post"s,
      on_response = retry_on_fail
    );
  };

on_response definition

Now we can write an on_response handler which will calls the request again if it failed and there are still retries_count available.

  retry_on_fail = [&](auto&& resp) {
    
 
    if ( resp.error && (retries_count > 0) ) {
      --retries_count;
      do_request();
    } else {
      // correct response
    }
  };

Don't forget to initiate the first try

  do_request();