added maxRetryDuration option to client

spotify.go

@@ -40,14 +40,19 @@ const (
 	rateLimitExceededStatusCode = 429
 )
 
+// ErrNoMorePages is the error returned when response header has a 'Retry-After'
+// duration longer then the configuerd max.
+var ErrMaxRetryDurationExceeded = errors.New("spotify: retry would take longer then configured max")
+
 // Client is a client for working with the Spotify Web API.
 // It is best to create this using spotify.New()
 type Client struct {
 	http    *http.Client
 	baseURL string
 
-	autoRetry      bool
-	acceptLanguage string
+	autoRetry        bool
+	acceptLanguage   string
+	maxRetryDuration time.Duration
 }
 
 type ClientOption func(client *Client)
@@ -74,6 +79,15 @@ func WithAcceptLanguage(lang string) ClientOption {
 	}
 }
 
+// WithMaxRetryDuration limits the amount of time that the client wil wait to retry afther being rate limited.
+// If the retry time is longer then the max, then the client will return an err
+// This option only works when auto retry is enabled
+func WithMaxRetryDuration(duration time.Duration) ClientOption {
+	return func(client *Client) {
+		client.maxRetryDuration = duration
+	}
+}
+
 // New returns a client for working with the Spotify Web API.
 // The provided httpClient must provide Authentication with the requests.
 // The auth package may be used to generate a suitable client.
@@ -230,10 +244,14 @@ func (c *Client) execute(req *http.Request, result interface{}, needsStatus ...i
 		if c.autoRetry &&
 			isFailure(resp.StatusCode, needsStatus) &&
 			shouldRetry(resp.StatusCode) {
+			duration := retryDuration(resp)
+			if c.maxRetryDuration > 0 && duration > c.maxRetryDuration {
+				return ErrMaxRetryDurationExceeded
+			}
 			select {
 			case <-req.Context().Done():
 				// If the context is cancelled, return the original error
-			case <-time.After(retryDuration(resp)):
+			case <-time.After(duration):
 				continue
 			}
 		}
@@ -285,10 +303,14 @@ func (c *Client) get(ctx context.Context, url string, result interface{}) error
 		defer resp.Body.Close()
 
 		if resp.StatusCode == rateLimitExceededStatusCode && c.autoRetry {
+			duration := retryDuration(resp)
+			if c.maxRetryDuration > 0 && duration > c.maxRetryDuration {
+				return ErrMaxRetryDurationExceeded
+			}
 			select {
 			case <-ctx.Done():
 				// If the context is cancelled, return the original error
-			case <-time.After(retryDuration(resp)):
+			case <-time.After(duration):
 				continue
 			}
 		}

spotify_test.go

@@ -2,14 +2,15 @@ package spotify
 
 import (
 	"context"
-	"golang.org/x/oauth2"
 	"io"
 	"net/http"
 	"net/http/httptest"
 	"os"
 	"strings"
 	"testing"
 	"time"
+
+	"golang.org/x/oauth2"
 )
 
 func testClient(code int, body io.Reader, validators ...func(*http.Request)) (*Client, *httptest.Server) {
@@ -104,6 +105,29 @@ func TestNewReleasesRateLimitExceeded(t *testing.T) {
 	}
 }
 
+func TestNewReleasesMaxRetry(t *testing.T) {
+	t.Parallel()
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Retry-After", "3660") // 61 minutes
+		w.WriteHeader(rateLimitExceededStatusCode)
+		_, _ = io.WriteString(w, `{ "error": { "message": "slow down", "status": 429 } }`)
+	})
+
+	server := httptest.NewServer(handler)
+	defer server.Close()
+
+	client := &Client{
+		http:             http.DefaultClient,
+		baseURL:          server.URL + "/",
+		autoRetry:        true,
+		maxRetryDuration: time.Hour,
+	}
+	_, err := client.NewReleases(context.Background())
+	if err != ErrMaxRetryDurationExceeded {
+		t.Errorf("Should throw 'ErrMaxRetryDurationExceeded' error, got '%s'", err)
+	}
+}
+
 func TestClient_Token(t *testing.T) {
 	// oauth setup for valid test token
 	config := oauth2.Config{
@@ -144,14 +168,14 @@ func TestClient_Token(t *testing.T) {
 
 	t.Run("non oauth2 transport", func(t *testing.T) {
 		client := &Client{
-			http:    http.DefaultClient,
+			http: http.DefaultClient,
 		}
 		_, err := client.Token()
 		if err == nil || err.Error() != "spotify: client not backed by oauth2 transport" {
 			t.Errorf("Should throw error: %s", "spotify: client not backed by oauth2 transport")
 		}
 	})
-	
+
 	t.Run("invalid token", func(t *testing.T) {
 		httpClient := config.Client(context.Background(), nil)
 		client := New(httpClient)