Add namespaces lister endpoint

This is required to list namespaces as part of #511.

The default namespace is matched, and any additional namespaces
must be annotated with the "openfaas" label. This is to prevent
kube-system, etc from being used.

Tested e2e with k3s/k8s 1.15 - the default ns showed, a new ns
was created and annotated, which then showed up in the results
subsequently.

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <[email protected]>

Gopkg.toml

@@ -4,7 +4,7 @@
 
 [[constraint]]
   name = "github.com/openfaas/faas-provider"
-  version = "0.10.1"
+  version = "0.10.2"
 
 [[constraint]]
   name = "github.com/gorilla/mux"

handlers/deploy.go

@@ -76,7 +76,7 @@ func MakeDeployHandler(functionNamespace string, factory k8s.FunctionFactory) ht
 			return
 		}
 
-		log.Println("Created deployment - " + request.Service + "," + namespace)
+		log.Printf("Deployment created: %s.%s\n", request.Service, namespace)
 
 		service := factory.Client.Core().Services(namespace)
 		serviceSpec := makeServiceSpec(request, factory)
@@ -89,8 +89,9 @@ func MakeDeployHandler(functionNamespace string, factory k8s.FunctionFactory) ht
 			return
 		}
 
-		log.Println("Created service - " + request.Service + "," + namespace)
-		log.Println(string(body))
+		log.Printf("Service created: %s.%s\n", request.Service, namespace)
+
+		// log.Println(string(body))
 
 		w.WriteHeader(http.StatusAccepted)
 
@@ -307,7 +308,6 @@ func createSelector(constraints []string) map[string]string {
 		}
 	}
 
-	// log.Println("selector: ", selector)
 	return selector
 }
 

handlers/namespaces.go

@@ -0,0 +1,65 @@
+// Copyright (c) Alex Ellis 2017. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+package handlers
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/kubernetes"
+)
+
+// MakeNamespacesLister builds a list of namespaces with an "openfaas" tag, or the default name
+func MakeNamespacesLister(defaultNamespace string, clientset *kubernetes.Clientset) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		log.Println("Query namespaces")
+
+		res := list(defaultNamespace, clientset)
+
+		out, _ := json.Marshal(res)
+		w.Header().Set("Content-Type", "application/json")
+
+		w.WriteHeader(http.StatusAccepted)
+		w.Write(out)
+	}
+}
+
+func list(defaultNamespace string, clientset *kubernetes.Clientset) []string {
+	listOptions := metav1.ListOptions{}
+	namespaces, err := clientset.CoreV1().Namespaces().List(listOptions)
+
+	set := []string{}
+
+	// Assume that an error means that a Role, instead of ClusterRole is being used
+	// the Role will not be able to list namespaces, so all functions are in the
+	// defaultNamespace
+	if err != nil {
+		log.Printf("Error listing namespaces: %s", err.Error())
+		set = append(set, defaultNamespace)
+		return set
+	}
+
+	for _, n := range namespaces.Items {
+		if _, ok := n.Annotations["openfaas"]; ok {
+			set = append(set, n.Name)
+		}
+	}
+
+	if !findNamespace(defaultNamespace, set) {
+		set = append(set, defaultNamespace)
+	}
+
+	return set
+}
+
+func findNamespace(target string, items []string) bool {
+	for _, n := range items {
+		if n == target {
+			return true
+		}
+	}
+	return false
+}

handlers/namespaces_test.go

@@ -0,0 +1,24 @@
+// Copyright (c) Alex Ellis 2017. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+package handlers
+
+import "testing"
+
+func Test_findNamespace_Found(t *testing.T) {
+	got := findNamespace("fn", []string{"fn", "openfaas-fn"})
+	want := true
+
+	if got != want {
+		t.Errorf("findNamespace - want: %v, got %v", want, got)
+	}
+}
+
+func Test_findNamespace_NotFound(t *testing.T) {
+	got := findNamespace("fn", []string{"openfaas-fn"})
+	want := false
+
+	if got != want {
+		t.Errorf("findNamespace - want: %v, got %v", want, got)
+	}
+}

server.go

@@ -67,17 +67,18 @@ func main() {
 	factory := k8s.NewFunctionFactory(clientset, deployConfig)
 
 	bootstrapHandlers := bootTypes.FaaSHandlers{
-		FunctionProxy:  handlers.MakeProxy(functionNamespace, cfg.ReadTimeout),
-		DeleteHandler:  handlers.MakeDeleteHandler(functionNamespace, clientset),
-		DeployHandler:  handlers.MakeDeployHandler(functionNamespace, factory),
-		FunctionReader: handlers.MakeFunctionReader(functionNamespace, clientset),
-		ReplicaReader:  handlers.MakeReplicaReader(functionNamespace, clientset),
-		ReplicaUpdater: handlers.MakeReplicaUpdater(functionNamespace, clientset),
-		UpdateHandler:  handlers.MakeUpdateHandler(functionNamespace, factory),
-		HealthHandler:  handlers.MakeHealthHandler(),
-		InfoHandler:    handlers.MakeInfoHandler(version.BuildVersion(), version.GitCommit),
-		SecretHandler:  handlers.MakeSecretHandler(functionNamespace, clientset),
-		LogHandler:     logs.NewLogHandlerFunc(handlers.NewLogRequestor(clientset, functionNamespace), cfg.WriteTimeout),
+		FunctionProxy:        handlers.MakeProxy(functionNamespace, cfg.ReadTimeout),
+		DeleteHandler:        handlers.MakeDeleteHandler(functionNamespace, clientset),
+		DeployHandler:        handlers.MakeDeployHandler(functionNamespace, factory),
+		FunctionReader:       handlers.MakeFunctionReader(functionNamespace, clientset),
+		ReplicaReader:        handlers.MakeReplicaReader(functionNamespace, clientset),
+		ReplicaUpdater:       handlers.MakeReplicaUpdater(functionNamespace, clientset),
+		UpdateHandler:        handlers.MakeUpdateHandler(functionNamespace, factory),
+		HealthHandler:        handlers.MakeHealthHandler(),
+		InfoHandler:          handlers.MakeInfoHandler(version.BuildVersion(), version.GitCommit),
+		SecretHandler:        handlers.MakeSecretHandler(functionNamespace, clientset),
+		LogHandler:           logs.NewLogHandlerFunc(handlers.NewLogRequestor(clientset, functionNamespace), cfg.WriteTimeout),
+		ListNamespaceHandler: handlers.MakeNamespacesLister(functionNamespace, clientset),
 	}
 
 	var port int