Validates that push request contains at least one sample

pkg/distributor/distributor.go

@@ -214,6 +214,10 @@ func (d *Distributor) Push(ctx context.Context, req *connect.Request[pushv1.Push
 		profiles = append(profiles, &profileTracker{profile: series})
 	}
 
+	if totalProfiles == 0 {
+		return nil, connect.NewError(connect.CodeInvalidArgument, fmt.Errorf("no profiles received"))
+	}
+
 	// validate the request
 	for _, series := range req.Msg.Series {
 		if err := validation.ValidateLabels(d.limits, tenantID, series.Labels); err != nil {

pkg/distributor/distributor_test.go

@@ -241,6 +241,38 @@ func Test_Limits(t *testing.T) {
 	})
 }
 
+func TestBadPushRequest(t *testing.T) {
+	mux := http.NewServeMux()
+	ing := newFakeIngester(t, false)
+	d, err := New(Config{
+		DistributorRing: ringConfig,
+	}, testhelper.NewMockRing([]ring.InstanceDesc{
+		{Addr: "foo"},
+	}, 3), func(addr string) (client.PoolClient, error) {
+		return ing, nil
+	}, newOverrides(t), nil, log.NewLogfmtLogger(os.Stdout))
+
+	require.NoError(t, err)
+	mux.Handle(pushv1connect.NewPusherServiceHandler(d, connect.WithInterceptors(tenant.NewAuthInterceptor(true))))
+	s := httptest.NewServer(mux)
+	defer s.Close()
+
+	client := pushv1connect.NewPusherServiceClient(http.DefaultClient, s.URL, connect.WithInterceptors(tenant.NewAuthInterceptor(true)))
+
+	_, err = client.Push(tenant.InjectTenantID(context.Background(), "foo"), connect.NewRequest(&pushv1.PushRequest{
+		Series: []*pushv1.RawProfileSeries{
+			{
+				Labels: []*typesv1.LabelPair{
+					{Name: "cluster", Value: "us-central1"},
+					{Name: "__name__", Value: "cpu"},
+				},
+			},
+		},
+	}))
+	require.Error(t, err)
+	require.Equal(t, connect.CodeInvalidArgument, connect.CodeOf(err))
+}
+
 func newOverrides(t *testing.T) *validation.Overrides {
 	t.Helper()
 	return validation.MockOverrides(func(defaults *validation.Limits, tenantLimits map[string]*validation.Limits) {