Switch to use Too Many Requests response code

pkg/api/errors/errors.go

@@ -25,6 +25,12 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util/errors"
 )
 
+// HTTP Status codes not in the golang http package.
+const (
+	StatusUnprocessableEntity = 422
+	StatusTooManyRequests     = 429
+)
+
 // StatusError is an error intended for consumption by a REST API server; it can also be
 // reconstructed by clients from a REST response. Public to allow easy type switches.
 type StatusError struct {
@@ -134,7 +140,7 @@ func NewInvalid(kind, name string, errs ValidationErrorList) error {
 	}
 	return &StatusError{api.Status{
 		Status: api.StatusFailure,
-		Code:   422, // RFC 4918: StatusUnprocessableEntity
+		Code:   StatusUnprocessableEntity, // RFC 4918: StatusUnprocessableEntity
 		Reason: api.StatusReasonInvalid,
 		Details: &api.StatusDetails{
 			Kind:   kind,

pkg/apiserver/apiserver.go

@@ -50,10 +50,6 @@ type defaultAPIServer struct {
 	group *APIGroupVersion
 }
 
-const (
-	StatusUnprocessableEntity = 422
-)
-
 // Handle returns a Handler function that exposes the provided storage interfaces
 // as RESTful resources at prefix, serialized by codec, and also includes the support
 // http resources.

pkg/apiserver/handlers.go

@@ -24,6 +24,7 @@ import (
 	"strings"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/auth/authorizer"
 	authhandlers "github.com/GoogleCloudPlatform/kubernetes/pkg/auth/handlers"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/httplog"
@@ -71,9 +72,10 @@ func RateLimit(rl util.RateLimiter, handler http.Handler) http.Handler {
 			handler.ServeHTTP(w, req)
 			return
 		}
-		w.WriteHeader(http.StatusServiceUnavailable)
+		// Return a 429 status indicating "Too Many Requests"
+		w.WriteHeader(errors.StatusTooManyRequests)
 		w.Header().Set("Retry-After", "1")
-		fmt.Fprintf(w, "Rate limit exceeded.")
+		fmt.Fprintf(w, "Rate limit is 1 QPS or a burst of 20")
 	})
 }
 
@@ -96,7 +98,7 @@ func RecoverPanics(handler http.Handler) http.Handler {
 				http.StatusTemporaryRedirect,
 				http.StatusConflict,
 				http.StatusNotFound,
-				StatusUnprocessableEntity,
+				errors.StatusUnprocessableEntity,
 			),
 		).Log()
 

pkg/client/request.go

@@ -483,7 +483,8 @@ func (r *Request) Do() Result {
 			continue
 		}
 
-		if resp.StatusCode == http.StatusServiceUnavailable {
+		// Check to see if we got a 429 Too Many Requests response code.
+		if resp.StatusCode == errors.StatusTooManyRequests {
 			if retries < 10 {
 				retries++
 				if waitFor := resp.Header.Get("Retry-After"); waitFor != "" {