naive retry golang

naive-retry.go

// Retry - http client with retry support
type Retry struct {
	http.RoundTripper
}

// Naive Retry - every 2 seconds
func (r *Retry) RoundTrip(req *http.Request) (*http.Response, error) {
	for {
		resp, err := r.RoundTripper.RoundTrip(req)

		if err == nil && resp.StatusCode < 500 {
			return resp, err
		}

		select {
                // check if canceled or timed-out 
		case <-req.Context().Done():
			return resp, req.Context().Err()
		case <-time.After(2 * time.Second):
		}
	}
}

func main() {
	c := &http.Client{
		Transport: &Retry{http.DefaultTransport},
	}

	req, err := http.NewRequest("GET", "https://www.google.com", nil)
	if err != nil {
		log.Fatalf("Could not create request")
	}

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	req = req.WithContext(ctx)
	resp, err := c.Do(req)
	if err != nil {
		log.Fatalln(err)
	}
	defer resp.Body.Close()

	log.Println(resp)

}