Refactor should retry

pkg/http/client.go

@@ -181,13 +181,11 @@ func (r *HTTPClient) Do(req *http.Request) (*http.Response, error) {
 			}
 		}
 
-		incr := r.shouldRetry(req, resp, err, attempt, r.rateLimitSleepSecs)
-		if incr == -1 {
+		if !r.shouldRetry(req, resp, err, attempt, r.rateLimitSleepSecs) {
 			break
-		} else if incr == 0 {
-			continue
 		}
-		attempt += incr
+		attempt++
+		continue
 	}
 	return resp, err
 }
@@ -240,53 +238,56 @@ func (r *HTTPClient) proxyDialer(proxyURL *url.URL) (proxy.Dialer, error) {
 	return nil, fmt.Errorf("unsupported proxy scheme: %s", proxyURL.Scheme)
 }
 
-// shouldRetry returns a number indicating whether the request should be retried
-// -1: don't retry
-// 0: retry indefinitely
-// 1: retry until maxRetries
-func (r *HTTPClient) shouldRetry(req *http.Request, resp *http.Response, err error, attempts, rateLimitSleep int) int {
-	if attempts >= r.maxRetries {
-		return -1
-	}
-
+// shouldRetry returns true if the request should be retried
+func (r *HTTPClient) shouldRetry(req *http.Request, resp *http.Response, err error, attempts, rateLimitSleep int) bool {
 	// assume that all addMagnet requests are always successful;
 	// don't retry to prevent duplicate torrents
 	if req.Host == "api.real-debrid.com" && strings.HasSuffix(req.URL.Path, "torrents/addMagnet") {
-		return -1
+		return false
 	}
 
 	if apiErr, ok := err.(*ApiErrorResponse); ok {
 		switch apiErr.Code {
 		case 5: // Slow down (retry infinitely)
 			secs := r.backoff(attempts, rateLimitSleep)
-			r.log.Debugf("API rate limit reached, retrying in %d seconds", secs/time.Second)
+			r.log.Debugf("API rate limit reached, attempt #%d, retrying in %d seconds", attempts+1, secs/time.Second)
 			time.Sleep(secs)
-			return 0
+			return true
 		case 34: // Too many requests (retry infinitely)
 			secs := r.backoff(attempts, rateLimitSleep)
-			r.log.Debugf("API rate limit reached, retrying in %d seconds", secs/time.Second)
+			r.log.Debugf("API rate limit reached, attempt #%d, retrying in %d seconds", attempts+1, secs/time.Second)
 			time.Sleep(secs)
-			return 0
+			return true
 		case 36: // Fair Usage Limit
 			secs := r.backoff(attempts, rateLimitSleep)
-			r.log.Debugf("Fair usage limit reached, retrying in %d seconds", secs/time.Second)
+			r.log.Debugf("Fair usage limit reached, attempt #%d, retrying in %d seconds", attempts+1, secs/time.Second)
 			time.Sleep(secs)
-			return 0
+			return true
 		case -1: // Internal error
-			r.log.Debugf("RD Internal error, attempt #%d, retrying", attempts+1)
-			return 1
+			if attempts >= r.maxRetries {
+				r.log.Debugf("RD Internal error, attempt #%d", attempts+1)
+				return false
+			}
+			secs := r.backoff(attempts, 1)
+			r.log.Debugf("RD Internal error, attempt #%d, retrying in %d seconds", attempts+1, secs/time.Second)
+			time.Sleep(secs)
+			return true
 		default:
-			return -1
+			return false
 		}
 	} else if downloadErr, ok := err.(*DownloadErrorResponse); ok {
 		switch downloadErr.Message {
 		case "invalid_download_code": // 404
+			if attempts >= r.maxRetries {
+				r.log.Debugf("Invalid download code, attempt #%d", attempts+1)
+				return false
+			}
 			secs := r.backoff(attempts, rateLimitSleep)
 			r.log.Debugf("Invalid download code, attempt #%d, retrying in %d seconds", attempts+1, secs/time.Second)
-			time.Sleep(r.backoff(attempts, rateLimitSleep))
-			return 1
+			time.Sleep(secs)
+			return true
 		default:
-			return -1
+			return false
 		}
 	}
 
@@ -296,13 +297,19 @@ func (r *HTTPClient) shouldRetry(req *http.Request, resp *http.Response, err err
 		// if the request has a Range header but the server doesn't respond with a Content-Range header
 		hasRangeHeader := req.Header.Get("Range") != "" && !strings.HasPrefix(req.Header.Get("Range"), "bytes=0-")
 		if okResponseCode && hasRangeHeader && resp.Header.Get("Content-Range") == "" {
-			return 0
+			return true
 		}
-		return -1
+		return false
 	}
 
-	r.log.Debugf("Request failed, attempt #%d, retrying (error=%v)", attempts+1, err)
-	return 1
+	if attempts >= r.maxRetries {
+		r.log.Debugf("Request failed, attempt #%d (error=%v)", attempts+1, err)
+		return false
+	}
+	secs := r.backoff(attempts, 1)
+	r.log.Debugf("Request failed, attempt #%d, retrying in %d seconds (error=%v)", attempts+1, secs/time.Second, err)
+	time.Sleep(secs)
+	return true
 }
 
 func backoffFunc(attempt, base int) time.Duration {