cleanup: go vet and golint run (#736)

* cleanup: go vet and golint run

Various cleanups trickered by go vet and golint.

* Fix tests and lowercase all errors

Lowercase all errors, some tests in kubernetes use errors from
kubernetes which do start with a capital letter.

6 files changed, 30 insertions, 31 deletions

diff --git a/middleware/kubernetes/federation.go b/middleware/kubernetes/federation.go
index 9a2908ded..4c058b839 100644
--- a/middleware/kubernetes/federation.go
+++ b/middleware/kubernetes/federation.go
@@ -7,6 +7,7 @@ import (
 	"github.com/coredns/coredns/middleware/etcd/msg"
 )
 
+// Federation holds TODO(...).
 type Federation struct {
 	name string
 	zone string
@@ -26,8 +27,8 @@ const (
 	//
 	// But importing above breaks coredns with flag collision of 'log_dir'
 
-	LabelAvailabilityZone = "failure-domain.beta.kubernetes.io/zone"
-	LabelRegion           = "failure-domain.beta.kubernetes.io/region"
+	labelAvailabilityZone = "failure-domain.beta.kubernetes.io/zone"
+	labelRegion           = "failure-domain.beta.kubernetes.io/region"
 )
 
 // stripFederation removes the federation segment from the segment list, if it
@@ -66,12 +67,12 @@ func (k *Kubernetes) federationCNAMERecord(r recordRequest) msg.Service {
 		if r.endpoint == "" {
 			return msg.Service{
 				Key:  strings.Join([]string{msg.Path(r.zone, "coredns"), r.typeName, r.federation, r.namespace, r.service}, "/"),
-				Host: strings.Join([]string{r.service, r.namespace, r.federation, r.typeName, node.Labels[LabelAvailabilityZone], node.Labels[LabelRegion], f.zone}, "."),
+				Host: strings.Join([]string{r.service, r.namespace, r.federation, r.typeName, node.Labels[labelAvailabilityZone], node.Labels[labelRegion], f.zone}, "."),
 			}
 		}
 		return msg.Service{
 			Key:  strings.Join([]string{msg.Path(r.zone, "coredns"), r.typeName, r.federation, r.namespace, r.service, r.endpoint}, "/"),
-			Host: strings.Join([]string{r.endpoint, r.service, r.namespace, r.federation, r.typeName, node.Labels[LabelAvailabilityZone], node.Labels[LabelRegion], f.zone}, "."),
+			Host: strings.Join([]string{r.endpoint, r.service, r.namespace, r.federation, r.typeName, node.Labels[labelAvailabilityZone], node.Labels[labelRegion], f.zone}, "."),
 		}
 	}
 
diff --git a/middleware/kubernetes/federation_test.go b/middleware/kubernetes/federation_test.go
index 2c33a544f..a938159ff 100644
--- a/middleware/kubernetes/federation_test.go
+++ b/middleware/kubernetes/federation_test.go
@@ -66,8 +66,8 @@ func (apiConnFedTest) GetNodeByName(name string) (api.Node, error) {
 		ObjectMeta: api.ObjectMeta{
 			Name: "test.node.foo.bar",
 			Labels: map[string]string{
-				LabelRegion:           "fd-r",
-				LabelAvailabilityZone: "fd-az",
+				labelRegion:           "fd-r",
+				labelAvailabilityZone: "fd-az",
 			},
 		},
 	}, nil
diff --git a/middleware/kubernetes/kubernetes.go b/middleware/kubernetes/kubernetes.go
index dea4a812d..abc4e603b 100644
--- a/middleware/kubernetes/kubernetes.go
+++ b/middleware/kubernetes/kubernetes.go
@@ -230,7 +230,7 @@ func (k *Kubernetes) InitKubeCache() (err error) {
 
 	kubeClient, err := kubernetes.NewForConfig(config)
 	if err != nil {
-		return fmt.Errorf("Failed to create kubernetes notification controller: %v", err)
+		return fmt.Errorf("failed to create kubernetes notification controller: %v", err)
 	}
 
 	if k.LabelSelector != nil {
@@ -238,7 +238,7 @@ func (k *Kubernetes) InitKubeCache() (err error) {
 		selector, err = unversionedapi.LabelSelectorAsSelector(k.LabelSelector)
 		k.Selector = &selector
 		if err != nil {
-			return fmt.Errorf("Unable to create Selector for LabelSelector '%s'.Error was: %s", k.LabelSelector, err)
+			return fmt.Errorf("unable to create Selector for LabelSelector '%s'.Error was: %s", k.LabelSelector, err)
 		}
 	}
 
diff --git a/middleware/kubernetes/kubernetes_test.go b/middleware/kubernetes/kubernetes_test.go
index 2bfff0c78..d740027f6 100644
--- a/middleware/kubernetes/kubernetes_test.go
+++ b/middleware/kubernetes/kubernetes_test.go
@@ -431,8 +431,8 @@ func (APIConnServiceTest) GetNodeByName(name string) (api.Node, error) {
 		ObjectMeta: api.ObjectMeta{
 			Name: "test.node.foo.bar",
 			Labels: map[string]string{
-				LabelRegion:           "fd-r",
-				LabelAvailabilityZone: "fd-az",
+				labelRegion:           "fd-r",
+				labelAvailabilityZone: "fd-az",
 			},
 		},
 	}, nil
diff --git a/middleware/kubernetes/setup.go b/middleware/kubernetes/setup.go
index 05eeaa02f..1f8a1f0e3 100644
--- a/middleware/kubernetes/setup.go
+++ b/middleware/kubernetes/setup.go
@@ -96,7 +96,7 @@ func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) {
 						for _, cidrStr := range args {
 							_, cidr, err := net.ParseCIDR(cidrStr)
 							if err != nil {
-								return nil, errors.New("Invalid cidr: " + cidrStr)
+								return nil, fmt.Errorf("invalid cidr: %s", cidrStr)
 							}
 							k8s.ReverseCidrs = append(k8s.ReverseCidrs, *cidr)
 
@@ -111,7 +111,7 @@ func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) {
 						case PodModeDisabled, PodModeInsecure, PodModeVerified:
 							k8s.PodMode = args[0]
 						default:
-							return nil, errors.New("Value for pods must be one of: disabled, verified, insecure")
+							return nil, fmt.Errorf("wrong value for pods: %s,  must be one of: disabled, verified, insecure", args[0])
 						}
 						continue
 					}
@@ -142,7 +142,7 @@ func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) {
 					if len(args) > 0 {
 						rp, err := time.ParseDuration(args[0])
 						if err != nil {
-							return nil, fmt.Errorf("Unable to parse resync duration value. Value provided was '%v'. Example valid values: '15s', '5m', '1h'. Error was: %v", args[0], err)
+							return nil, fmt.Errorf("unable to parse resync duration value: '%v': %v", args[0], err)
 						}
 						k8s.ResyncPeriod = rp
 						continue
@@ -154,7 +154,7 @@ func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) {
 						labelSelectorString := strings.Join(args, " ")
 						ls, err := unversionedapi.ParseToLabelSelector(labelSelectorString)
 						if err != nil {
-							return nil, fmt.Errorf("Unable to parse label selector. Value provided was '%v'. Error was: %v", labelSelectorString, err)
+							return nil, fmt.Errorf("unable to parse label selector value: '%v': %v", labelSelectorString, err)
 						}
 						k8s.LabelSelector = ls
 						continue
@@ -185,17 +185,15 @@ func kubernetesParse(c *caddy.Controller) (*Kubernetes, error) {
 							zone: args[1],
 						})
 						continue
-					} else {
-						return nil, fmt.Errorf("Incorrect number of arguments for federation. Got %v, expect 2.", len(args))
 					}
-					return nil, c.ArgErr()
+					return nil, fmt.Errorf("incorrect number of arguments for federation, got %v, expected 2", len(args))
 
 				}
 			}
 			return k8s, nil
 		}
 	}
-	return nil, errors.New("Kubernetes setup called without keyword 'kubernetes' in Corefile")
+	return nil, errors.New("kubernetes setup called without keyword 'kubernetes' in Corefile")
 }
 
 const (
diff --git a/middleware/kubernetes/setup_test.go b/middleware/kubernetes/setup_test.go
index d150daba9..8414d76fd 100644
--- a/middleware/kubernetes/setup_test.go
+++ b/middleware/kubernetes/setup_test.go
@@ -223,7 +223,7 @@ func TestKubernetesParse(t *testing.T) {
 			"no kubernetes keyword",
 			"",
 			true,
-			"Kubernetes setup called without keyword 'kubernetes' in Corefile",
+			"kubernetes setup called without keyword 'kubernetes' in Corefile",
 			-1,
 			-1,
 			defaultResyncPeriod,
@@ -255,7 +255,7 @@ func TestKubernetesParse(t *testing.T) {
     endpoint
 }`,
 			true,
-			"Wrong argument count or unexpected line ending after 'endpoint'",
+			"rong argument count or unexpected line ending",
 			-1,
 			-1,
 			defaultResyncPeriod,
@@ -272,7 +272,7 @@ func TestKubernetesParse(t *testing.T) {
 	namespaces
 }`,
 			true,
-			"Parse error: Wrong argument count or unexpected line ending after 'namespaces'",
+			"rong argument count or unexpected line ending",
 			-1,
 			-1,
 			defaultResyncPeriod,
@@ -289,7 +289,7 @@ func TestKubernetesParse(t *testing.T) {
     resyncperiod
 }`,
 			true,
-			"Wrong argument count or unexpected line ending after 'resyncperiod'",
+			"rong argument count or unexpected line ending",
 			-1,
 			0,
 			0 * time.Minute,
@@ -306,7 +306,7 @@ func TestKubernetesParse(t *testing.T) {
     resyncperiod 15
 }`,
 			true,
-			"Unable to parse resync duration value. Value provided was ",
+			"unable to parse resync duration value",
 			-1,
 			0,
 			0 * time.Second,
@@ -323,7 +323,7 @@ func TestKubernetesParse(t *testing.T) {
     resyncperiod abc
 }`,
 			true,
-			"Unable to parse resync duration value. Value provided was ",
+			"unable to parse resync duration value",
 			-1,
 			0,
 			0 * time.Second,
@@ -340,7 +340,7 @@ func TestKubernetesParse(t *testing.T) {
     labels
 }`,
 			true,
-			"Wrong argument count or unexpected line ending after 'labels'",
+			"rong argument count or unexpected line ending",
 			-1,
 			0,
 			0 * time.Second,
@@ -357,7 +357,7 @@ func TestKubernetesParse(t *testing.T) {
     labels environment in (production, qa
 }`,
 			true,
-			"Unable to parse label selector. Value provided was",
+			"unable to parse label selector",
 			-1,
 			0,
 			0 * time.Second,
@@ -429,7 +429,7 @@ func TestKubernetesParse(t *testing.T) {
 	pods giant_seed
 }`,
 			true,
-			"Value for pods must be one of: disabled, verified, insecure",
+			"rong value for pods",
 			-1,
 			0,
 			defaultResyncPeriod,
@@ -460,12 +460,12 @@ func TestKubernetesParse(t *testing.T) {
 		},
 		// cidrs ok
 		{
-			"Invalid cidr: hard",
+			"invalid cidr: hard",
 			`kubernetes coredns.local {
 	cidrs hard dry
 }`,
 			true,
-			"Invalid cidr: hard",
+			"invalid cidr: hard",
 			-1,
 			0,
 			defaultResyncPeriod,
@@ -483,7 +483,7 @@ func TestKubernetesParse(t *testing.T) {
 	fallthrough junk
 }`,
 			true,
-			"Wrong argument count",
+			"rong argument count",
 			-1,
 			0,
 			defaultResyncPeriod,
@@ -559,7 +559,7 @@ func TestKubernetesParse(t *testing.T) {
 	federation starship
 }`,
 			true,
-			`Incorrect number of arguments for federation. Got 1, expect 2.`,
+			`incorrect number of arguments for federation`,
 			-1,
 			0,
 			defaultResyncPeriod,