Run golint and go vet (#276)

Cleanup the errors and removed deadcode along the way. The leaves
some error laying around, mostly about commenting exported identifier.
We should look hard if those really are needed.

middleware/cache/setup.go

@@ -56,7 +56,7 @@ func cacheParse(c *caddy.Controller) (int, []string, error) {
 				}
 			}
 
-			for i, _ := range origins {
+			for i := range origins {
 				origins[i] = middleware.Host(origins[i]).Normalize()
 			}
 			return ttl, origins, nil

middleware/dnssec/responsewriter.go

@@ -10,16 +10,16 @@ import (
 	"github.com/miekg/dns"
 )
 
-type DnssecResponseWriter struct {
+type ResponseWriter struct {
 	dns.ResponseWriter
 	d Dnssec
 }
 
-func NewDnssecResponseWriter(w dns.ResponseWriter, d Dnssec) *DnssecResponseWriter {
-	return &DnssecResponseWriter{w, d}
+func NewDnssecResponseWriter(w dns.ResponseWriter, d Dnssec) *ResponseWriter {
+	return &ResponseWriter{w, d}
 }
 
-func (d *DnssecResponseWriter) WriteMsg(res *dns.Msg) error {
+func (d *ResponseWriter) WriteMsg(res *dns.Msg) error {
 	// By definition we should sign anything that comes back, we should still figure out for
 	// which zone it should be.
 	state := request.Request{W: d.ResponseWriter, Req: res}
@@ -38,13 +38,13 @@ func (d *DnssecResponseWriter) WriteMsg(res *dns.Msg) error {
 	return d.ResponseWriter.WriteMsg(res)
 }
 
-func (d *DnssecResponseWriter) Write(buf []byte) (int, error) {
+func (d *ResponseWriter) Write(buf []byte) (int, error) {
 	log.Printf("[WARNING] Dnssec called with Write: not signing reply")
 	n, err := d.ResponseWriter.Write(buf)
 	return n, err
 }
 
-func (d *DnssecResponseWriter) Hijack() {
+func (d *ResponseWriter) Hijack() {
 	d.ResponseWriter.Hijack()
 	return
 }

middleware/file/reload_test.go

@@ -39,7 +39,7 @@ func TestZoneReload(t *testing.T) {
 		t.Fatalf("expected 5 RRs, got %d", len(z.All()))
 	}
 	if err := ioutil.WriteFile(fileName, []byte(reloadZone2Test), 0644); err != nil {
-		t.Fatalf("failed to write new zone data", err)
+		t.Fatalf("failed to write new zone data: %s", err)
 	}
 	// Could still be racy, but we need to wait a bit for the event to be seen
 	time.Sleep(1 * time.Second)

middleware/file/secondary.go

@@ -176,7 +176,6 @@ Restart:
 			}
 		}
 	}
-	return nil
 }
 
 // The maximum difference between two serial numbers. If the difference between

middleware/file/tree/less.go

@@ -39,7 +39,6 @@ func less(a, b string) int {
 		i++
 		aj, bj = ai, bi
 	}
-	return 0
 }
 
 func doDDD(b []byte) {

middleware/kubernetes/setup.go

@@ -107,7 +107,7 @@ func kubernetesParse(c *caddy.Controller) (Kubernetes, error) {
 					if len(args) != 0 {
 						k8s.ResyncPeriod, err = time.ParseDuration(args[0])
 						if err != nil {
-							err = errors.New(fmt.Sprintf("Unable to parse resync duration value. Value provided was '%v'. Example valid values: '15s', '5m', '1h'. Error was: %v", args[0], err))
+							err = 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 Kubernetes{}, err
 						}
 					} else {
@@ -119,7 +119,7 @@ func kubernetesParse(c *caddy.Controller) (Kubernetes, error) {
 						labelSelectorString := strings.Join(args, " ")
 						k8s.LabelSelector, err = unversionedapi.ParseToLabelSelector(labelSelectorString)
 						if err != nil {
-							err = errors.New(fmt.Sprintf("Unable to parse label selector. Value provided was '%v'. Error was: %v", labelSelectorString, err))
+							err = fmt.Errorf("Unable to parse label selector. Value provided was '%v'. Error was: %v", labelSelectorString, err)
 							return Kubernetes{}, err
 						}
 					} else {

middleware/kubernetes/subzone_test.go

@@ -21,7 +21,7 @@ var examplesSubzoneConflict = map[string]bool{
 	"":        false,
 }
 
-func TestsubzoneConflict(t *testing.T) {
+func TestSubzoneConflict(t *testing.T) {
 	for z, expected := range examplesSubzoneConflict {
 		actual, conflicts := subzoneConflict(confZones, z)
 

middleware/metrics/metrics.go

@@ -30,7 +30,7 @@ type Metrics struct {
 	Addr      string
 	ln        net.Listener
 	mux       *http.ServeMux
-	Once      sync.Once
+	Once      *sync.Once
 	ZoneNames []string
 }
 

middleware/metrics/setup.go

@@ -47,7 +47,7 @@ func prometheusParse(c *caddy.Controller) (Metrics, error) {
 		}
 		met.ZoneNames = make([]string, len(c.ServerBlockKeys))
 		copy(met.ZoneNames, c.ServerBlockKeys)
-		for i, _ := range met.ZoneNames {
+		for i := range met.ZoneNames {
 			met.ZoneNames[i] = middleware.Host(met.ZoneNames[i]).Normalize()
 		}
 		args := c.RemainingArgs()
@@ -79,6 +79,6 @@ func prometheusParse(c *caddy.Controller) (Metrics, error) {
 	return met, err
 }
 
-var metricsOnce sync.Once
+var metricsOnce *sync.Once
 
 const addr = "localhost:9153"

middleware/normalize.go

@@ -7,6 +7,7 @@ import (
 	"github.com/miekg/dns"
 )
 
+// Zones respresents a lists of zone names.
 type Zones []string
 
 // Matches checks is qname is a subdomain of any of the zones in z.  The match
@@ -27,7 +28,7 @@ func (z Zones) Matches(qname string) string {
 
 // Normalize fully qualifies all zones in z.
 func (z Zones) Normalize() {
-	for i, _ := range z {
+	for i := range z {
 		z[i] = Name(z[i]).Normalize()
 	}
 }
@@ -47,10 +48,11 @@ func (n Name) Matches(child string) bool {
 // Normalize lowercases and makes n fully qualified.
 func (n Name) Normalize() string { return strings.ToLower(dns.Fqdn(string(n))) }
 
-// Host represents a host from the Corefile, may contain port.
 type (
-	Host string
-	Addr string
+	// Host represents a host from the Corefile, may contain port.
+	Host string // Host represents a host from the Corefile, may contain port.
+	// Addr resprents an address in the Corefile.
+	Addr string // Addr resprents an address in the Corefile.
 )
 
 // Normalize will return the host portion of host, stripping

middleware/pkg/rcode/rcode.go

@@ -6,6 +6,8 @@ import (
 	"github.com/miekg/dns"
 )
 
+// ToString convert the rcode to the offical DNS string, or to "RCODE"+value if the RCODE
+// value is unknown.
 func ToString(rcode int) string {
 	if str, ok := dns.RcodeToString[rcode]; ok {
 		return str

middleware/pkg/response/classify.go

@@ -2,14 +2,20 @@ package response
 
 import "github.com/miekg/dns"
 
+// Type is the type of the message
 type Type int
 
 const (
-	Success    Type = iota
-	NameError       // NXDOMAIN in header, SOA in auth.
-	NoData          // NOERROR in header, SOA in auth.
-	Delegation      // NOERROR in header, NS in auth, optionally fluff in additional (not checked).
-	OtherError      // Don't cache these.
+	// Success indicates a positive reply
+	Success Type = iota
+	// NameError is a NXDOMAIN in header, SOA in auth.
+	NameError
+	// NoData indicated name found, but not the type: NOERROR in header, SOA in auth.
+	NoData
+	// Delegation is a msg with a pointer to another nameserver: NOERROR in header, NS in auth, optionally fluff in additional (not checked).
+	Delegation
+	// OtherError indicated any other error: don't cache these.
+	OtherError
 )
 
 // Classify classifies a message, it returns the Type.

middleware/pkg/storage/fs.go

@@ -25,7 +25,7 @@ type dir http.Dir
 //
 // CoreDir will default to "$HOME/.coredns" on Unix, but it's location can be overriden with the COREDNSPATH
 // environment variable.
-var CoreDir dir = dir(fsPath())
+var CoreDir = dir(fsPath())
 
 func (d dir) Zone(z string) dir {
 	if z != "." && z[len(z)-2] == '.' {

middleware/pkg/storage/fs_test.go

@@ -7,7 +7,7 @@ import (
 	"testing"
 )
 
-func TestfsPath(t *testing.T) {
+func TestFsPath(t *testing.T) {
 	if actual := fsPath(); !strings.HasSuffix(actual, ".coredns") {
 		t.Errorf("Expected path to be a .coredns folder, got: %v", actual)
 	}

middleware/pprof/pprof.go

@@ -13,13 +13,14 @@ type Handler struct {
 }
 
 func (h *Handler) Startup() error {
-	if ln, err := net.Listen("tcp", addr); err != nil {
+	ln, err := net.Listen("tcp", addr)
+	if err != nil {
 		log.Printf("[ERROR] Failed to start pprof handler: %s", err)
 		return err
-	} else {
-		h.ln = ln
 	}
 
+	h.ln = ln
+
 	h.mux = http.NewServeMux()
 	h.mux.HandleFunc(path+"/", pp.Index)
 	h.mux.HandleFunc(path+"/cmdline", pp.Cmdline)

middleware/secondary/setup.go

@@ -56,7 +56,7 @@ func secondaryParse(c *caddy.Controller) (file.Zones, error) {
 			if len(args) > 0 {
 				origins = args
 			}
-			for i, _ := range origins {
+			for i := range origins {
 				origins[i] = middleware.Host(origins[i]).Normalize()
 				z[origins[i]] = file.NewZone(origins[i], "stdin")
 				names = append(names, origins[i])

middleware/test/helpers.go

@@ -149,12 +149,12 @@ func Section(t *testing.T, tc Case, sect Sect, rr []dns.RR) bool {
 				return false
 			}
 			if x.SignerName != section[i].(*dns.RRSIG).SignerName {
-				t.Errorf("rr %d should have a SignerName of %d, but has %d", i, section[i].(*dns.RRSIG).SignerName, x.SignerName)
+				t.Errorf("rr %d should have a SignerName of %s, but has %s", i, section[i].(*dns.RRSIG).SignerName, x.SignerName)
 				return false
 			}
 		case *dns.NSEC:
 			if x.NextDomain != section[i].(*dns.NSEC).NextDomain {
-				t.Errorf("rr %d should have a NextDomain of %d, but has %d", i, section[i].(*dns.NSEC).NextDomain, x.NextDomain)
+				t.Errorf("rr %d should have a NextDomain of %s, but has %s", i, section[i].(*dns.NSEC).NextDomain, x.NextDomain)
 				return false
 			}
 			// TypeBitMap