QueryService: Return application/json and better errors (#84234)

pkg/util/errutil/errhttp/writer.go

@@ -7,6 +7,9 @@ import (
 	"net/http"
 	"reflect"
 
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apiserver/pkg/endpoints/request"
+
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/util/errutil"
 )
@@ -20,6 +23,14 @@ type ErrorOptions struct {
 	logger   log.Logger
 }
 
+type k8sError struct {
+	metav1.Status `json:",inline"`
+
+	// Internal values that do not have a clean home in the standard Status object
+	MessageID string         `json:"messageId"`
+	Extra     map[string]any `json:"extra,omitempty"`
+}
+
 // Write writes an error to the provided [http.ResponseWriter] with the
 // appropriate HTTP status and JSON payload from [errutil.Error].
 // Write also logs the provided error to either the "request-errors"
@@ -43,10 +54,49 @@ func Write(ctx context.Context, err error, w http.ResponseWriter, opts ...func(E
 
 	logError(ctx, gErr, opt)
 
+	var rsp any
 	pub := gErr.Public()
 	w.Header().Add("Content-Type", "application/json")
 	w.WriteHeader(pub.StatusCode)
-	err = json.NewEncoder(w).Encode(pub)
+	rsp = pub
+
+	// When running in k8s, this will return a v1 status
+	// Typically, k8s handlers should directly support error negotiation, however
+	// when implementing handlers directly this will maintain compatibility with client-go
+	info, ok := request.RequestInfoFrom(ctx)
+	if ok {
+		status := &k8sError{
+			Status: metav1.Status{
+				Status:  metav1.StatusFailure,
+				Code:    int32(pub.StatusCode),
+				Message: pub.Message,
+				Details: &metav1.StatusDetails{
+					Name:  info.Name,
+					Group: info.APIGroup,
+				},
+			},
+			// Add the internal values into
+			MessageID: pub.MessageID,
+			Extra:     pub.Extra,
+		}
+		switch pub.StatusCode {
+		case 400:
+			status.Reason = metav1.StatusReasonBadRequest
+		case 401:
+			status.Reason = metav1.StatusReasonUnauthorized
+		case 403:
+			status.Reason = metav1.StatusReasonForbidden
+		case 404:
+			status.Reason = metav1.StatusReasonNotFound
+		case 500: // many reasons things could map here
+			status.Reason = metav1.StatusReasonInternalError
+		case 504:
+			status.Reason = metav1.StatusReasonTimeout
+		}
+		rsp = status
+	}
+
+	err = json.NewEncoder(w).Encode(rsp)
 	if err != nil {
 		defaultLogger.FromContext(ctx).Error("error while writing error", "error", err)
 	}

pkg/util/errutil/errhttp/writer_test.go

@@ -7,15 +7,39 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"k8s.io/apiserver/pkg/endpoints/request"
 
 	"github.com/grafana/grafana/pkg/util/errutil"
 )
 
 func TestWrite(t *testing.T) {
-	ctx := context.Background()
+	// Error without k8s context
+	recorder := doError(t, context.Background())
+	assert.Equal(t, http.StatusGatewayTimeout, recorder.Code)
+	assert.JSONEq(t, `{"message": "Timeout", "messageId": "test.thisIsExpected", "statusCode": 504}`, recorder.Body.String())
+
+	// Another request, but within the k8s framework
+	recorder = doError(t, request.WithRequestInfo(context.Background(), &request.RequestInfo{
+		APIGroup: "TestGroup",
+	}))
+	assert.Equal(t, http.StatusGatewayTimeout, recorder.Code)
+	assert.JSONEq(t, `{
+		"status": "Failure",
+		"reason": "Timeout",
+		"metadata": {},
+		"messageId": "test.thisIsExpected",
+		"message": "Timeout",
+		"details": { "group": "TestGroup" },
+		"code": 504
+	  }`, recorder.Body.String())
+}
+
+func doError(t *testing.T, ctx context.Context) *httptest.ResponseRecorder {
+	t.Helper()
+
 	const msgID = "test.thisIsExpected"
 	base := errutil.Timeout(msgID)
-	handler := func(writer http.ResponseWriter, request *http.Request) {
+	handler := func(writer http.ResponseWriter, _ *http.Request) {
 		Write(ctx, base.Errorf("got expected error"), writer)
 	}
 
@@ -23,7 +47,5 @@ func TestWrite(t *testing.T) {
 	recorder := httptest.NewRecorder()
 
 	handler(recorder, req)
-
-	assert.Equal(t, http.StatusGatewayTimeout, recorder.Code)
-	assert.JSONEq(t, `{"message": "Timeout", "messageId": "test.thisIsExpected", "statusCode": 504}`, recorder.Body.String())
+	return recorder
 }