From f79440e9170441f7cabfdd94604b6707019c28f1 Mon Sep 17 00:00:00 2001
From: Jerome Hayakawa-Guiard <jerome.guiard@binance.com>
Date: Thu, 6 Oct 2022 20:58:21 +0200
Subject: [PATCH] fix: allowemptyservice issue#9423

---
 .../crd/fixtures/with_empty_services_ts.yml   | 31 +++++++++++++
 pkg/provider/kubernetes/crd/kubernetes.go     |  8 +++-
 .../kubernetes/crd/kubernetes_test.go         | 46 +++++++++++++++++++
 3 files changed, 83 insertions(+), 2 deletions(-)
 create mode 100644 pkg/provider/kubernetes/crd/fixtures/with_empty_services_ts.yml

diff --git a/pkg/provider/kubernetes/crd/fixtures/with_empty_services_ts.yml b/pkg/provider/kubernetes/crd/fixtures/with_empty_services_ts.yml
new file mode 100644
index 0000000000..a5ad919db8
--- /dev/null
+++ b/pkg/provider/kubernetes/crd/fixtures/with_empty_services_ts.yml
@@ -0,0 +1,31 @@
+apiVersion: traefik.containo.us/v1alpha1
+kind: IngressRoute
+metadata:
+  name: test.route
+  namespace: default
+
+spec:
+  entryPoints:
+    - foo
+
+  routes:
+    - match: Host(`foo.com`) && PathPrefix(`/bar`)
+      kind: Rule
+      priority: 12
+      services:
+        - name: tr-svc-es
+          kind: TraefikService
+
+---
+apiVersion: traefik.containo.us/v1alpha1
+kind: TraefikService
+metadata:
+  name: tr-svc-es
+  namespace: default
+
+spec:
+  weighted:
+    services:
+      - name: whoami-without-endpoints-subsets
+        weight: 1
+        port: 80
diff --git a/pkg/provider/kubernetes/crd/kubernetes.go b/pkg/provider/kubernetes/crd/kubernetes.go
index a43345e675..6bec807b4a 100644
--- a/pkg/provider/kubernetes/crd/kubernetes.go
+++ b/pkg/provider/kubernetes/crd/kubernetes.go
@@ -114,6 +114,10 @@ func (p *Provider) Provide(configurationChan chan<- dynamic.Message, pool *safe.
 		logger.Warn("ExternalName service loading is enabled, please ensure that this is expected (see AllowExternalNameServices option)")
 	}
 
+	if p.AllowEmptyServices {
+		logger.Warn("EmptyService service loading is enabled (see AllowEmptyServices option)")
+	}
+
 	pool.GoCtx(func(ctxPool context.Context) {
 		operation := func() error {
 			eventsChan, err := k8sClient.WatchAll(p.Namespaces, ctxPool.Done())
@@ -292,7 +296,7 @@ func (p *Provider) loadConfigurationFromCRD(ctx context.Context, client Client)
 		}
 	}
 
-	cb := configBuilder{client: client, allowCrossNamespace: p.AllowCrossNamespace, allowExternalNameServices: p.AllowExternalNameServices}
+	cb := configBuilder{client: client, allowCrossNamespace: p.AllowCrossNamespace, allowExternalNameServices: p.AllowExternalNameServices, allowEmptyServices: p.AllowEmptyServices}
 
 	for _, service := range client.GetTraefikServices() {
 		err := cb.buildTraefikService(ctx, service, conf.HTTP.Services)
@@ -578,7 +582,7 @@ func (p *Provider) createErrorPageMiddleware(client Client, namespace string, er
 		Query:  errorPage.Query,
 	}
 
-	balancerServerHTTP, err := configBuilder{client: client, allowCrossNamespace: p.AllowCrossNamespace, allowExternalNameServices: p.AllowExternalNameServices}.buildServersLB(namespace, errorPage.Service.LoadBalancerSpec)
+	balancerServerHTTP, err := configBuilder{client: client, allowCrossNamespace: p.AllowCrossNamespace, allowExternalNameServices: p.AllowExternalNameServices, allowEmptyServices: p.AllowEmptyServices}.buildServersLB(namespace, errorPage.Service.LoadBalancerSpec)
 	if err != nil {
 		return nil, nil, err
 	}
diff --git a/pkg/provider/kubernetes/crd/kubernetes_test.go b/pkg/provider/kubernetes/crd/kubernetes_test.go
index 7465c8faef..86525e79a3 100644
--- a/pkg/provider/kubernetes/crd/kubernetes_test.go
+++ b/pkg/provider/kubernetes/crd/kubernetes_test.go
@@ -4037,6 +4037,52 @@ func TestLoadIngressRoutes(t *testing.T) {
 				TLS: &dynamic.TLSConfiguration{},
 			},
 		},
+		{
+			desc:               "TraefikService, empty service allowed",
+			allowEmptyServices: true,
+			paths:              []string{"services.yml", "with_empty_services_ts.yml"},
+			expected: &dynamic.Configuration{
+				UDP: &dynamic.UDPConfiguration{
+					Routers:  map[string]*dynamic.UDPRouter{},
+					Services: map[string]*dynamic.UDPService{},
+				},
+				TCP: &dynamic.TCPConfiguration{
+					Routers:     map[string]*dynamic.TCPRouter{},
+					Middlewares: map[string]*dynamic.TCPMiddleware{},
+					Services:    map[string]*dynamic.TCPService{},
+				},
+				HTTP: &dynamic.HTTPConfiguration{
+					Routers: map[string]*dynamic.Router{
+						"default-test-route-6b204d94623b3df4370c": {
+							EntryPoints: []string{"foo"},
+							Service:     "default-tr-svc-es",
+							Rule:        "Host(`foo.com`) && PathPrefix(`/bar`)",
+							Priority:    12,
+						},
+					},
+					Middlewares: map[string]*dynamic.Middleware{},
+					Services: map[string]*dynamic.Service{
+						"default-tr-svc-es": {
+							Weighted: &dynamic.WeightedRoundRobin{
+								Services: []dynamic.WRRService{
+									{
+										Name:   "default-whoami-without-endpoints-subsets-80",
+										Weight: func(i int) *int { return &i }(1),
+									},
+								},
+							},
+						},
+						"default-whoami-without-endpoints-subsets-80": {
+							LoadBalancer: &dynamic.ServersLoadBalancer{
+								PassHostHeader: Bool(true),
+							},
+						},
+					},
+					ServersTransports: map[string]*dynamic.ServersTransport{},
+				},
+				TLS: &dynamic.TLSConfiguration{},
+			},
+		},
 	}
 
 	for _, test := range testCases {