Refactoring of k8s helpers

middleware/kubernetes/controller.go

@@ -5,8 +5,6 @@ import (
 	"sync"
 	"time"
 
-	"github.com/miekg/coredns/middleware/kubernetes/util"
-
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/client/cache"
 	client "k8s.io/kubernetes/pkg/client/unversioned"
@@ -19,6 +17,19 @@ var (
 	namespace = api.NamespaceAll
 )
 
+// storeToNamespaceLister makes a Store that lists Namespaces.
+type storeToNamespaceLister struct {
+	cache.Store
+}
+
+// List lists all Namespaces in the store.
+func (s *storeToNamespaceLister) List() (ns api.NamespaceList, err error) {
+	for _, m := range s.Store.List() {
+		ns.Items = append(ns.Items, *(m.(*api.Namespace)))
+	}
+	return ns, nil
+}
+
 type dnsController struct {
 	client *client.Client
 
@@ -30,7 +41,7 @@ type dnsController struct {
 
 	svcLister  cache.StoreToServiceLister
 	endpLister cache.StoreToEndpointsLister
-	nsLister   util.StoreToNamespaceLister
+	nsLister   storeToNamespaceLister
 
 	// stopLock is used to enforce only a single call to Stop is active.
 	// Needed because we allow stopping through an http endpoint and

middleware/kubernetes/kubernetes.go

@@ -4,13 +4,14 @@ package kubernetes
 import (
 	"errors"
 	"log"
+	"strings"
 	"time"
 
 	"github.com/miekg/coredns/middleware"
 	"github.com/miekg/coredns/middleware/etcd/msg"
 	"github.com/miekg/coredns/middleware/kubernetes/nametemplate"
-	"github.com/miekg/coredns/middleware/kubernetes/util"
 	"github.com/miekg/coredns/middleware/pkg/dnsutil"
+	dns_strings "github.com/miekg/coredns/middleware/pkg/strings"
 	"github.com/miekg/coredns/middleware/proxy"
 
 	"github.com/miekg/dns"
@@ -126,21 +127,21 @@ func (k *Kubernetes) Records(name string, exact bool) ([]msg.Service, error) {
 	if namespace == "" {
 		err := errors.New("Parsing query string did not produce a namespace value. Assuming wildcard namespace.")
 		log.Printf("[WARN] %v\n", err)
-		namespace = util.WildcardStar
+		namespace = "*"
 	}
 
 	if serviceName == "" {
 		err := errors.New("Parsing query string did not produce a serviceName value. Assuming wildcard serviceName.")
 		log.Printf("[WARN] %v\n", err)
-		serviceName = util.WildcardStar
+		serviceName = "*"
 	}
 
-	nsWildcard := util.SymbolContainsWildcard(namespace)
+	nsWildcard := symbolContainsWildcard(namespace)
-	serviceWildcard := util.SymbolContainsWildcard(serviceName)
+	serviceWildcard := symbolContainsWildcard(serviceName)
 
 	// Abort if the namespace does not contain a wildcard, and namespace is not published per CoreFile
 	// Case where namespace contains a wildcard is handled in Get(...) method.
-	if (!nsWildcard) && (len(k.Namespaces) > 0) && (!util.StringInSlice(namespace, k.Namespaces)) {
+	if (!nsWildcard) && (len(k.Namespaces) > 0) && (!dns_strings.StringInSlice(namespace, k.Namespaces)) {
 		return nil, nil
 	}
 
@@ -190,7 +191,7 @@ func (k *Kubernetes) Get(namespace string, nsWildcard bool, servicename string,
 		if symbolMatches(namespace, item.Namespace, nsWildcard) && symbolMatches(servicename, item.Name, serviceWildcard) {
 			// If namespace has a wildcard, filter results against Corefile namespace list.
 			// (Namespaces without a wildcard were filtered before the call to this function.)
-			if nsWildcard && (len(k.Namespaces) > 0) && (!util.StringInSlice(item.Namespace, k.Namespaces)) {
+			if nsWildcard && (len(k.Namespaces) > 0) && (!dns_strings.StringInSlice(item.Namespace, k.Namespaces)) {
 				continue
 			}
 			resultItems = append(resultItems, item)
@@ -205,9 +206,9 @@ func symbolMatches(queryString string, candidateString string, wildcard bool) bo
 	switch {
 	case !wildcard:
 		result = (queryString == candidateString)
-	case queryString == util.WildcardStar:
+	case queryString == "*":
 		result = true
-	case queryString == util.WildcardAny:
+	case queryString == "any":
 		result = true
 	}
 	return result
@@ -239,3 +240,8 @@ const (
 	hostmaster = "hostmaster"
 	k8sTimeout = 5 * time.Second
 )
+
+// symbolContainsWildcard checks whether symbol contains a wildcard value
+func symbolContainsWildcard(symbol string) bool {
+	return (strings.Contains(symbol, "*") || (symbol == "any"))
+}

middleware/kubernetes/kubernetes_test.go

@@ -0,0 +1,25 @@
+package kubernetes
+
+import "testing"
+
+// Test data for TestSymbolContainsWildcard cases.
+var testdataSymbolContainsWildcard = []struct {
+	Symbol         string
+	ExpectedResult bool
+}{
+	{"mynamespace", false},
+	{"*", true},
+	{"any", true},
+	{"my*space", true},
+	{"*space", true},
+	{"myname*", true},
+}
+
+func TestSymbolContainsWildcard(t *testing.T) {
+	for _, example := range testdataSymbolContainsWildcard {
+		actualResult := symbolContainsWildcard(example.Symbol)
+		if actualResult != example.ExpectedResult {
+			t.Errorf("Expected SymbolContainsWildcard result '%v' for example string='%v'. Instead got result '%v'.", example.ExpectedResult, example.Symbol, actualResult)
+		}
+	}
+}

middleware/kubernetes/nametemplate/nametemplate.go

@@ -4,7 +4,7 @@ import (
 	"errors"
 	"strings"
 
-	"github.com/miekg/coredns/middleware/kubernetes/util"
+	dns_strings "github.com/miekg/coredns/middleware/pkg/strings"
 )
 
 // Likely symbols that require support:
@@ -125,7 +125,7 @@ func (t *NameTemplate) GetTypeFromSegmentArray(segments []string) string {
 	typeSegment := t.GetSymbolFromSegmentArray("type", segments)
 
 	// Limit type to known types symbols
-	if util.StringInSlice(typeSegment, types) {
+	if dns_strings.StringInSlice(typeSegment, types) {
 		return ""
 	}
 

middleware/kubernetes/util/util.go

@@ -1,42 +0,0 @@
-// Package kubernetes/util provides helper functions for the kubernetes middleware
-package util
-
-import (
-	"strings"
-
-	"k8s.io/kubernetes/pkg/api"
-	"k8s.io/kubernetes/pkg/client/cache"
-)
-
-// StringInSlice check whether string a is a member of slice.
-func StringInSlice(a string, slice []string) bool {
-	for _, b := range slice {
-		if b == a {
-			return true
-		}
-	}
-	return false
-}
-
-// SymbolContainsWildcard checks whether symbol contains a wildcard value
-func SymbolContainsWildcard(symbol string) bool {
-	return (strings.Contains(symbol, WildcardStar) || (symbol == WildcardAny))
-}
-
-const (
-	WildcardStar = "*"
-	WildcardAny  = "any"
-)
-
-// StoreToNamespaceLister makes a Store that lists Namespaces.
-type StoreToNamespaceLister struct {
-	cache.Store
-}
-
-// List lists all Namespaces in the store.
-func (s *StoreToNamespaceLister) List() (ns api.NamespaceList, err error) {
-	for _, m := range s.Store.List() {
-		ns.Items = append(ns.Items, *(m.(*api.Namespace)))
-	}
-	return ns, nil
-}

middleware/pkg/strings/slice.go

@@ -0,0 +1,11 @@
+package strings
+
+// StringInSlice check whether string a is a member of slice.
+func StringInSlice(a string, slice []string) bool {
+	for _, b := range slice {
+		if b == a {
+			return true
+		}
+	}
+	return false
+}

middleware/pkg/strings/slice_test.go

@@ -1,4 +1,4 @@
-package util
+package strings
 
 import (
 	"testing"
@@ -31,25 +31,3 @@ func TestStringInSlice(t *testing.T) {
 		}
 	}
 }
-
-// Test data for TestSymbolContainsWildcard cases.
-var testdataSymbolContainsWildcard = []struct {
-	Symbol         string
-	ExpectedResult bool
-}{
-	{"mynamespace", false},
-	{"*", true},
-	{"any", true},
-	{"my*space", true},
-	{"*space", true},
-	{"myname*", true},
-}
-
-func TestSymbolContainsWildcard(t *testing.T) {
-	for _, example := range testdataSymbolContainsWildcard {
-		actualResult := SymbolContainsWildcard(example.Symbol)
-		if actualResult != example.ExpectedResult {
-			t.Errorf("Expected SymbolContainsWildcard result '%v' for example string='%v'. Instead got result '%v'.", example.ExpectedResult, example.Symbol, actualResult)
-		}
-	}
-}