Use static local cluster endpoints to hit listeners with rds config

envoy-sidecar/configurer/configure.go

@@ -18,20 +18,31 @@ type MainListener struct {
 }
 
 type RouteDomain struct {
-	Name   string
-	Domain string
-	Port   int
+	Cluster string
+	Domain  string
+	Name    string
+	Port    int
 }
 type TargetListener struct {
 	Name            string
 	Port            int
 	RouteConfigName string
 }
 
-type Cluster struct {
+type StaticCluster struct {
+	Name string
+	Port int
+}
+
+type DynamicCluster struct {
 	Name string
 }
 
+type Clusters struct {
+	Dynamic []DynamicCluster
+	Static  []StaticCluster
+}
+
 type XdsCluster struct {
 	XdsServerAddress string
 	XdsServerPort    string
@@ -133,13 +144,14 @@ func makeEnvoyConfig(nodeID, envoySidecarTargets, XdsServerAddress, XdsServerPor
 // and routeConfig names. Clusters names should be derived from the above and
 // follow the form: service.namespace.port to comply with the xds naming
 // limitations and how semaphore-xds configures cluster names.
-func extractConfigFromTargets(envoySidecarTargets string) (MainListener, []TargetListener, []Cluster) {
+func extractConfigFromTargets(envoySidecarTargets string) (MainListener, []TargetListener, Clusters) {
 	port := EnvoyMainListenPort
 	main := MainListener{
 		Port: port,
 	}
 	domains := []RouteDomain{}
 	listeners := []TargetListener{}
+	staticClusters := []StaticCluster{}
 	for _, target := range strings.Split(envoySidecarTargets, ",") {
 		port++
 		lName := fmt.Sprintf("listener_%d", port)
@@ -149,20 +161,30 @@ func extractConfigFromTargets(envoySidecarTargets string) (MainListener, []Targe
 			RouteConfigName: target,
 		})
 		rName := fmt.Sprintf("route_%d", port)
+		cName := fmt.Sprintf("localhost_%d", port)
 		domains = append(domains, RouteDomain{
-			Name:   rName,
-			Domain: target,
-			Port:   port,
+			Cluster: cName,
+			Domain:  target,
+			Name:    rName,
+			Port:    port,
+		})
+		staticClusters = append(staticClusters, StaticCluster{
+			Name: cName,
+			Port: port,
 		})
 	}
 	main.Domains = domains
 
-	clusters := []Cluster{}
+	dynamicClusters := []DynamicCluster{}
 	for _, l := range listeners {
 		clusterName := strings.Join(strings.Split(l.RouteConfigName, ":"), ".")
-		clusters = append(clusters, Cluster{
+		dynamicClusters = append(dynamicClusters, DynamicCluster{
 			Name: clusterName,
 		})
 	}
+	clusters := Clusters{
+		Dynamic: dynamicClusters,
+		Static:  staticClusters,
+	}
 	return main, listeners, clusters
 }

envoy-sidecar/configurer/templates/clusters.tmpl

@@ -1,4 +1,4 @@
-{{- range . }}
+{{- range .Dynamic }}
   - name: {{ .Name }}
     http2_protocol_options: {}
     type: EDS
@@ -12,3 +12,17 @@
             - envoy_grpc:
                 cluster_name: xds_cluster
 {{- end }}
+{{- range .Static }}
+  - name: {{ .Name }}
+    connect_timeout: 5s
+    type: STATIC
+    load_assignment:
+      cluster_name: {{ .Name }}
+      endpoints:
+        - lb_endpoints:
+            - endpoint:
+                address:
+                  socket_address:
+                    address: 127.0.0.1
+                    port_value: {{ .Port }}
+{{- end }}

envoy-sidecar/configurer/templates/main-listener.tmpl

@@ -13,8 +13,10 @@
             - name: {{ .Name }}
               domains: ["{{ .Domain }}"]
               routes:
-              - match: { prefix: "" }
-                redirect: { port_redirect: {{ .Port }} }
+              - match:
+                  prefix: ""
+                route:
+                  cluster: {{ .Cluster }}
             {{- end }}
           http_filters:
           - name: envoy.filters.http.router