fix(godaddy): Handle missing Retry-After header gracefully

provider/godaddy/client.go

@@ -28,6 +28,7 @@ import (
 	"strconv"
 	"time"
 
+	log "github.com/sirupsen/logrus"
 	"golang.org/x/time/rate"
 
 	"sigs.k8s.io/external-dns/pkg/apis/externaldns"
@@ -41,6 +42,11 @@ var (
 	ErrAPIDown = errors.New("godaddy: the GoDaddy API is down")
 )
 
+// error codes
+const (
+	ErrCodeQuotaExceeded = "QUOTA_EXCEEDED"
+)
+
 // APIError error
 type APIError struct {
 	Code    string
@@ -129,7 +135,13 @@ func NewClient(useOTE bool, apiKey, apiSecret string) (*Client, error) {
 
 	// Get and check the configuration
 	if err := client.validate(); err != nil {
-		return nil, err
+		var apiErr *APIError
+		// Quota Exceeded errors are limited to the endpoint being called. Other endpoints are not affected when we hit
+		// the quota limit on the endpoint used for validation. We can safely ignore this error.
+		// Quota limits on other endpoints will be logged by their respective calls.
+		if ok := errors.As(err, &apiErr); ok && apiErr.Code != ErrCodeQuotaExceeded {
+			return nil, err
+		}
 	}
 	return &client, nil
 }
@@ -230,7 +242,11 @@ func (c *Client) Do(req *http.Request) (*http.Response, error) {
 	resp, err := c.Client.Do(req)
 	// In case of several clients behind NAT we still can hit rate limit
 	for i := 1; i < 3 && err == nil && resp.StatusCode == 429; i++ {
-		retryAfter, _ := strconv.ParseInt(resp.Header.Get("Retry-After"), 10, 0)
+		retryAfter, err := strconv.ParseInt(resp.Header.Get("Retry-After"), 10, 0)
+		if err != nil {
+			log.Error("Rate-limited response did not contain a valid Retry-After header, quota likely exceeded")
+			break
+		}
 
 		jitter := rand.Int63n(retryAfter)
 		retryAfterSec := retryAfter + jitter/2

provider/godaddy/client_test.go

@@ -0,0 +1,56 @@
+package godaddy
+
+import (
+	"errors"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"golang.org/x/time/rate"
+)
+
+// Tests that
+func TestClient_DoWhenQuotaExceeded(t *testing.T) {
+	assert := assert.New(t)
+
+	// Mock server to return 429 with a JSON payload
+	mockServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusTooManyRequests)
+		_, err := w.Write([]byte(`{"code": "QUOTA_EXCEEDED", "message": "rate limit exceeded"}`))
+		if err != nil {
+			t.Fatalf("Failed to write response: %v", err)
+		}
+	}))
+	defer mockServer.Close()
+
+	client := Client{
+		APIKey:      "",
+		APISecret:   "",
+		APIEndPoint: mockServer.URL,
+		Client:      &http.Client{},
+		// Add one token every second
+		Ratelimiter: rate.NewLimiter(rate.Every(time.Second), 60),
+		Timeout:     DefaultTimeout,
+	}
+
+	req, err := client.NewRequest("GET", "/v1/domains/example.net/records", nil, false)
+	if err != nil {
+		t.Fatalf("Failed to create request: %v", err)
+	}
+
+	resp, err := client.Do(req)
+	assert.Nil(err, "A CODE_EXCEEDED response should not return an error")
+	assert.Equal(http.StatusTooManyRequests, resp.StatusCode, "Expected a 429 response")
+
+	respContents := GDErrorResponse{}
+	err = client.UnmarshalResponse(resp, &respContents)
+	if assert.NotNil(err) {
+		var apiErr *APIError
+		errors.As(err, &apiErr)
+		assert.Equal("QUOTA_EXCEEDED", apiErr.Code)
+		assert.Equal("rate limit exceeded", apiErr.Message)
+	}
+}