retry logic now supported for HTTP 429 code

pester.go

@@ -277,8 +277,9 @@ func (c *Client) pester(p params) (*http.Response, error) {
 				}
 
 				// Early return if we have a valid result
-				// Only retry (ie, continue the loop) on 5xx status codes
-				if err == nil && resp.StatusCode < 500 {
+				// Only retry (ie, continue the loop) on 5xx status codes and 429
+
+				if err == nil && resp.StatusCode < 500 && resp.StatusCode != 429 {
 					multiplexCh <- result{resp: resp, err: err, req: n, retry: i}
 					return
 				}

pester_test.go

@@ -40,6 +40,69 @@ func TestConcurrentRequests(t *testing.T) {
 	}
 }
 
+func TestConcurrentRequestsWith429(t *testing.T) {
+	t.Parallel()
+
+	c := New()
+	c.Concurrency = 3
+	c.KeepLog = true
+
+	port, err := serverWith429()
+	if err != nil {
+		t.Fatal("unable to start server", err)
+	}
+
+	url := fmt.Sprintf("http://localhost:%d", port)
+
+	response, err := c.Get(url)
+	if err != nil {
+		t.Fatal("unable to GET", err)
+	}
+	c.Wait()
+
+	response.Body.Close()
+	c.Wait()
+
+	// in the event of an error, let's see what the logs were
+	t.Log("\n", c.LogString())
+
+	if got, want := c.LogErrCount(), c.Concurrency*c.MaxRetries; got != want {
+		t.Errorf("got %d attempts, want %d", got, want)
+	}
+}
+
+func TestMaxRetriesConcurrentRequestsWith429(t *testing.T) {
+	t.Parallel()
+
+	c := New()
+	c.Concurrency = 3
+	c.KeepLog = true
+	c.MaxRetries = 5
+
+	port, err := serverWith429()
+	if err != nil {
+		t.Fatal("unable to start server", err)
+	}
+
+	url := fmt.Sprintf("http://localhost:%d", port)
+
+	response, err := c.Get(url)
+	if err != nil {
+		t.Fatal("unable to GET", err)
+	}
+	c.Wait()
+
+	response.Body.Close()
+	c.Wait()
+
+	// in the event of an error, let's see what the logs were
+	t.Log("\n", c.LogString())
+
+	if got, want := c.LogErrCount(), c.Concurrency*c.MaxRetries; got != want {
+		t.Errorf("got %d attempts, want %d", got, want)
+	}
+}
+
 func TestConcurrent2Retry0(t *testing.T) {
 	t.Parallel()
 
@@ -64,6 +127,36 @@ func TestConcurrent2Retry0(t *testing.T) {
 	}
 }
 
+func TestConcurrent2Retry0for429(t *testing.T) {
+	t.Parallel()
+
+	c := New()
+	c.Concurrency = 2
+	c.MaxRetries = 0
+	c.KeepLog = true
+
+	port, err := serverWith429()
+	if err != nil {
+		t.Fatal("unable to start server", err)
+	}
+
+	url := fmt.Sprintf("http://localhost:%d", port)
+
+	_, getErr := c.Get(url)
+
+	if getErr != nil {
+		t.Fatal("unable to GET", getErr)
+	}
+	c.Wait()
+
+	// in the event of an error, let's see what the logs were
+	t.Log("\n", c.LogString())
+
+	if got, want := c.LogErrCount(), c.Concurrency; got != want {
+		t.Errorf("got %d attempts, want %d", got, want)
+	}
+}
+
 func TestDefaultBackoff(t *testing.T) {
 	t.Parallel()
 
@@ -506,3 +599,33 @@ func timeoutServer(timeout time.Duration) (int, error) {
 
 	return port, nil
 }
+
+func serverWith429() (int, error) {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
+
+		w.WriteHeader(http.StatusTooManyRequests)
+		w.Write([]byte("429 Too many requests"))
+	})
+	l, err := net.Listen("tcp", ":0")
+	if err != nil {
+		return -1, fmt.Errorf("unable to secure listener %v", err)
+	}
+	go func() {
+		if err := http.Serve(l, mux); err != nil {
+			log.Fatalf("slow-server error %v", err)
+		}
+	}()
+
+	var port int
+	_, sport, err := net.SplitHostPort(l.Addr().String())
+	if err == nil {
+		port, err = strconv.Atoi(sport)
+	}
+
+	if err != nil {
+		return -1, fmt.Errorf("unable to determine port %v", err)
+	}
+
+	return port, nil
+}