Add support for multiple gloo namespaces in one External DNS instance

docs/tutorials/gloo-proxy.md

@@ -25,7 +25,7 @@ spec:
         image: registry.k8s.io/external-dns/external-dns:v0.13.2
         args:
         - --source=gloo-proxy
-        - --gloo-namespace=custom-gloo-system # gloo system namespace. Omit to use the default (gloo-system)
+        - --gloo-namespace=custom-gloo-system # comma separated gloo system namespace list. Omit to use the default (gloo-system)
         - --provider=aws
         - --registry=txt
         - --txt-owner-id=my-identifier
@@ -93,7 +93,7 @@ spec:
         image: registry.k8s.io/external-dns/external-dns:v0.13.2
         args:
         - --source=gloo-proxy
-        - --gloo-namespace=custom-gloo-system # gloo system namespace. Omit to use the default (gloo-system)
+        - --gloo-namespace=custom-gloo-system # comma separated gloo system namespace list. Omit to use the default (gloo-system)
         - --provider=aws
         - --registry=txt
         - --txt-owner-id=my-identifier

pkg/apis/externaldns/types.go

@@ -398,7 +398,7 @@ func (cfg *Config) ParseFlags(args []string) error {
 	app.Flag("contour-load-balancer", "The fully-qualified name of the Contour load balancer service. (default: heptio-contour/contour)").Default("heptio-contour/contour").StringVar(&cfg.ContourLoadBalancerService)
 
 	// Flags related to Gloo
-	app.Flag("gloo-namespace", "Gloo namespace. (default: gloo-system)").Default("gloo-system").StringVar(&cfg.GlooNamespace)
+	app.Flag("gloo-namespace", "Coma separated list of gloo namespaces. (default: gloo-system)").Default("gloo-system").StringVar(&cfg.GlooNamespace)
 
 	// Flags related to Skipper RouteGroup
 	app.Flag("skipper-routegroup-groupversion", "The resource version for skipper routegroup").Default(source.DefaultRoutegroupVersion).StringVar(&cfg.SkipperRouteGroupVersion)

pkg/apis/externaldns/types_test.go

@@ -136,7 +136,7 @@ var (
 		KubeConfig:                  "/some/path",
 		RequestTimeout:              time.Second * 77,
 		ContourLoadBalancerService:  "heptio-contour-other/contour-other",
-		GlooNamespace:               "gloo-not-system",
+		GlooNamespace:               "gloo-not-system,gloo-second-system",
 		SkipperRouteGroupVersion:    "zalando.org/v2",
 		Sources:                     []string{"service", "ingress", "connector"},
 		Namespace:                   "namespace",
@@ -266,7 +266,7 @@ func TestParseFlags(t *testing.T) {
 				"--kubeconfig=/some/path",
 				"--request-timeout=77s",
 				"--contour-load-balancer=heptio-contour-other/contour-other",
-				"--gloo-namespace=gloo-not-system",
+				"--gloo-namespace=gloo-not-system,gloo-second-system",
 				"--skipper-routegroup-groupversion=zalando.org/v2",
 				"--source=service",
 				"--source=ingress",
@@ -391,7 +391,7 @@ func TestParseFlags(t *testing.T) {
 				"EXTERNAL_DNS_KUBECONFIG":                      "/some/path",
 				"EXTERNAL_DNS_REQUEST_TIMEOUT":                 "77s",
 				"EXTERNAL_DNS_CONTOUR_LOAD_BALANCER":           "heptio-contour-other/contour-other",
-				"EXTERNAL_DNS_GLOO_NAMESPACE":                  "gloo-not-system",
+				"EXTERNAL_DNS_GLOO_NAMESPACE":                  "gloo-not-system,gloo-second-system",
 				"EXTERNAL_DNS_SKIPPER_ROUTEGROUP_GROUPVERSION": "zalando.org/v2",
 				"EXTERNAL_DNS_SOURCE":                          "service\ningress\nconnector",
 				"EXTERNAL_DNS_NAMESPACE":                       "namespace",

source/gloo_proxy.go

@@ -81,15 +81,15 @@ type proxyVirtualHostMetadataSource struct {
 type glooSource struct {
 	dynamicKubeClient dynamic.Interface
 	kubeClient        kubernetes.Interface
-	glooNamespace     string
+	glooNamespaces    []string
 }
 
 // NewGlooSource creates a new glooSource with the given config
-func NewGlooSource(dynamicKubeClient dynamic.Interface, kubeClient kubernetes.Interface, glooNamespace string) (Source, error) {
+func NewGlooSource(dynamicKubeClient dynamic.Interface, kubeClient kubernetes.Interface, glooNamespaces string) (Source, error) {
 	return &glooSource{
 		dynamicKubeClient,
 		kubeClient,
-		glooNamespace,
+		strings.Split(glooNamespaces, ","),
 	}, nil
 }
 
@@ -100,32 +100,34 @@ func (gs *glooSource) AddEventHandler(ctx context.Context, handler func()) {
 func (gs *glooSource) Endpoints(ctx context.Context) ([]*endpoint.Endpoint, error) {
 	endpoints := []*endpoint.Endpoint{}
 
-	proxies, err := gs.dynamicKubeClient.Resource(proxyGVR).Namespace(gs.glooNamespace).List(ctx, metav1.ListOptions{})
-	if err != nil {
-		return nil, err
-	}
-	for _, obj := range proxies.Items {
-		proxy := proxy{}
-		jsonString, err := obj.MarshalJSON()
-		if err != nil {
-			return nil, err
-		}
-		err = json.Unmarshal(jsonString, &proxy)
+	for _, ns := range gs.glooNamespaces {
+		proxies, err := gs.dynamicKubeClient.Resource(proxyGVR).Namespace(ns).List(ctx, metav1.ListOptions{})
 		if err != nil {
 			return nil, err
 		}
-		log.Debugf("Gloo: Find %s proxy", proxy.Metadata.Name)
-		proxyTargets, err := gs.proxyTargets(ctx, proxy.Metadata.Name)
-		if err != nil {
-			return nil, err
-		}
-		log.Debugf("Gloo[%s]: Find %d target(s) (%+v)", proxy.Metadata.Name, len(proxyTargets), proxyTargets)
-		proxyEndpoints, err := gs.generateEndpointsFromProxy(ctx, &proxy, proxyTargets)
-		if err != nil {
-			return nil, err
+		for _, obj := range proxies.Items {
+			proxy := proxy{}
+			jsonString, err := obj.MarshalJSON()
+			if err != nil {
+				return nil, err
+			}
+			err = json.Unmarshal(jsonString, &proxy)
+			if err != nil {
+				return nil, err
+			}
+			log.Debugf("Gloo: Find %s proxy", proxy.Metadata.Name)
+			proxyTargets, err := gs.proxyTargets(ctx, proxy.Metadata.Name, ns)
+			if err != nil {
+				return nil, err
+			}
+			log.Debugf("Gloo[%s]: Find %d target(s) (%+v)", proxy.Metadata.Name, len(proxyTargets), proxyTargets)
+			proxyEndpoints, err := gs.generateEndpointsFromProxy(ctx, &proxy, proxyTargets)
+			if err != nil {
+				return nil, err
+			}
+			log.Debugf("Gloo[%s]: Generate %d endpoint(s)", proxy.Metadata.Name, len(proxyEndpoints))
+			endpoints = append(endpoints, proxyEndpoints...)
 		}
-		log.Debugf("Gloo[%s]: Generate %d endpoint(s)", proxy.Metadata.Name, len(proxyEndpoints))
-		endpoints = append(endpoints, proxyEndpoints...)
 	}
 	return endpoints, nil
 }
@@ -168,8 +170,8 @@ func (gs *glooSource) annotationsFromProxySource(ctx context.Context, virtualHos
 	return annotations, nil
 }
 
-func (gs *glooSource) proxyTargets(ctx context.Context, name string) (endpoint.Targets, error) {
-	svc, err := gs.kubeClient.CoreV1().Services(gs.glooNamespace).Get(ctx, name, metav1.GetOptions{})
+func (gs *glooSource) proxyTargets(ctx context.Context, name string, namespace string) (endpoint.Targets, error) {
+	svc, err := gs.kubeClient.CoreV1().Services(namespace).Get(ctx, name, metav1.GetOptions{})
 	if err != nil {
 		return nil, err
 	}