add golangci-lint linter (coredns#5499)

.github/workflows/golangci-lint.yml

@@ -0,0 +1,16 @@
+name: golangci-lint
+on:
+  pull_request:
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/setup-go@v3
+        with:
+          go-version: '1.18'
+      - uses: actions/checkout@v3
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v3
+        with:
+          version: v1.46.2

.golangci.yml

@@ -0,0 +1,13 @@
+run:
+  timeout: 5m
+linters:
+  disable-all: true
+  enable:
+    - deadcode
+    - govet
+    - ineffassign
+    - staticcheck
+    - structcheck
+    - typecheck
+    - varcheck
+    - whitespace

core/dnsserver/address.go

@@ -49,7 +49,6 @@ func newOverlapZone() *zoneOverlap {
 // registerAndCheck adds a new zoneAddr for validation, it returns information about existing or overlapping with already registered
 // we consider that an unbound address is overlapping all bound addresses for same zone, same port
 func (zo *zoneOverlap) registerAndCheck(z zoneAddr) (existingZone *zoneAddr, overlappingZone *zoneAddr) {
-
 	if exist, ok := zo.registeredAddr[z]; ok {
 		// exact same zone already registered
 		return &exist, nil

core/dnsserver/address_test.go

@@ -43,7 +43,6 @@ func TestSplitProtocolHostPort(t *testing.T) {
 		if port != test.port {
 			t.Errorf("Test %d: (address = %s) expected port with value %s but got %s", i, test.input, test.port, port)
 		}
-
 	}
 }
 
@@ -92,7 +91,6 @@ func TestOverlapAddressChecker(t *testing.T) {
 		},
 		},
 	} {
-
 		checker := newOverlapZone()
 		for _, call := range test.sequence {
 			same, overlap := checker.registerAndCheck(call.zone)
@@ -108,10 +106,8 @@ func TestOverlapAddressChecker(t *testing.T) {
 					if overlap.String() != call.overlapKey {
 						t.Errorf("Test %d: error, for zone %s, 'overlap Key' (%v) has not the expected value (%v)", i, sZone, overlap.String(), call.overlapKey)
 					}
-
 				}
 			}
-
 		}
 	}
 }

core/dnsserver/onstartup_test.go

@@ -5,7 +5,6 @@ import (
 )
 
 func TestRegex1035PrefSyntax(t *testing.T) {
-
 	testCases := []struct {
 		zone     string
 		expected bool

core/dnsserver/register.go

@@ -138,7 +138,6 @@ func (h *dnsContext) InspectServerBlocks(sourceFile string, serverBlocks []caddy
 
 // MakeServers uses the newly-created siteConfigs to create and return a list of server instances.
 func (h *dnsContext) MakeServers() ([]caddy.Server, error) {
-
 	// Now that all Keys and Directives are parsed and initialized
 	// lets verify that there is no overlap on the zones and addresses to listen for
 	errValid := h.validateZonesAndListeningAddresses()
@@ -197,7 +196,6 @@ func (h *dnsContext) MakeServers() ([]caddy.Server, error) {
 			}
 			servers = append(servers, s)
 		}
-
 	}
 
 	return servers, nil
@@ -262,11 +260,9 @@ func (h *dnsContext) validateZonesAndListeningAddresses() error {
 			if overlapZone != nil {
 				return fmt.Errorf("cannot serve %s - zone overlap listener capacity with %v", akey.String(), overlapZone.String())
 			}
-
 		}
 	}
 	return nil
-
 }
 
 // groupSiteConfigsByListenAddr groups site configs by their listen

core/dnsserver/register_test.go

@@ -114,7 +114,6 @@ func TestGroupingServers(t *testing.T) {
 		for _, v := range test.expectedGroups {
 			if _, ok := groups[v]; !ok {
 				t.Errorf("Test %d : expected value %v to be in the group, was not", i, v)
-
 			}
 		}
 	}

core/dnsserver/server.go

@@ -51,7 +51,6 @@ type Server struct {
 // NewServer returns a new CoreDNS server and compiles all plugins in to it. By default CH class
 // queries are blocked unless queries from enableChaos are loaded.
 func NewServer(addr string, group []*Config) (*Server, error) {
-
 	s := &Server{
 		Addr:         addr,
 		zones:        make(map[string]*Config),
@@ -174,7 +173,6 @@ func (s *Server) ListenPacket() (net.PacketConn, error) {
 // immediately.
 // This implements Caddy.Stopper interface.
 func (s *Server) Stop() (err error) {
-
 	if runtime.GOOS != "windows" {
 		// force connections to close after timeout
 		done := make(chan struct{})

core/dnsserver/server_grpc.go

@@ -82,7 +82,6 @@ func (s *ServergRPC) ServePacket(p net.PacketConn) error { return nil }
 
 // Listen implements caddy.TCPServer interface.
 func (s *ServergRPC) Listen() (net.Listener, error) {
-
 	l, err := reuseport.Listen("tcp", s.Addr[len(transport.GRPC+"://"):])
 	if err != nil {
 		return nil, err

core/dnsserver/server_https.go

@@ -104,7 +104,6 @@ func (s *ServerHTTPS) ServePacket(p net.PacketConn) error { return nil }
 
 // Listen implements caddy.TCPServer interface.
 func (s *ServerHTTPS) Listen() (net.Listener, error) {
-
 	l, err := reuseport.Listen("tcp", s.Addr[len(transport.HTTPS+"://"):])
 	if err != nil {
 		return nil, err
@@ -141,7 +140,6 @@ func (s *ServerHTTPS) Stop() error {
 // ServeHTTP is the handler that gets the HTTP request and converts to the dns format, calls the plugin
 // chain, converts it back and write it to the client.
 func (s *ServerHTTPS) ServeHTTP(w http.ResponseWriter, r *http.Request) {
-
 	if !s.validRequest(r) {
 		http.Error(w, "", http.StatusNotFound)
 		s.countResponse(http.StatusNotFound)

plugin/acl/acl.go

@@ -88,7 +88,6 @@ RulesCheckLoop:
 				return dns.RcodeSuccess, nil
 			}
 		}
-
 	}
 
 	RequestAllowCount.WithLabelValues(metrics.WithServer(ctx)).Inc()

plugin/auto/walk.go

@@ -12,7 +12,6 @@ import (
 
 // Walk will recursively walk of the file under l.directory and adds the one that match l.re.
 func (a Auto) Walk() error {
-
 	// TODO(miek): should add something so that we don't stomp on each other.
 
 	toDelete := make(map[string]bool)

plugin/autopath/autopath.go

@@ -135,7 +135,6 @@ func (a *AutoPath) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Ms
 		w.WriteMsg(msg)
 		autoPathCount.WithLabelValues(metrics.WithServer(ctx)).Add(1)
 		return rcode, err
-
 	}
 	if plugin.ClientWrite(firstRcode) {
 		w.WriteMsg(firstReply)

plugin/azure/azure.go

@@ -134,7 +134,6 @@ func (h *Azure) updateZones(ctx context.Context) error {
 		return fmt.Errorf("errors updating zones: %v", errs)
 	}
 	return nil
-
 }
 
 func updateZoneFromPublicResourceSet(recordSet publicdns.RecordSetListResultPage, newZ *file.Zone) {
@@ -297,7 +296,6 @@ func updateZoneFromPrivateResourceSet(recordSet privatedns.RecordSetListResultPa
 				Target: dns.Fqdn(*CNAME)}
 			newZ.Insert(cname)
 		}
-
 	}
 }
 

plugin/azure/setup.go

@@ -29,20 +29,24 @@ func setup(c *caddy.Controller) error {
 
 	publicDNSClient := publicAzureDNS.NewRecordSetsClient(env.Values[auth.SubscriptionID])
 	if publicDNSClient.Authorizer, err = env.GetAuthorizer(); err != nil {
+		cancel()
 		return plugin.Error("azure", err)
 	}
 
 	privateDNSClient := privateAzureDNS.NewRecordSetsClient(env.Values[auth.SubscriptionID])
 	if privateDNSClient.Authorizer, err = env.GetAuthorizer(); err != nil {
+		cancel()
 		return plugin.Error("azure", err)
 	}
 
 	h, err := New(ctx, publicDNSClient, privateDNSClient, keys, accessMap)
 	if err != nil {
+		cancel()
 		return plugin.Error("azure", err)
 	}
 	h.Fall = fall
 	if err := h.Run(ctx); err != nil {
+		cancel()
 		return plugin.Error("azure", err)
 	}
 

plugin/backend_lookup.go

@@ -23,7 +23,6 @@ func A(ctx context.Context, b ServiceBackend, zone string, state request.Request
 	dup := make(map[string]struct{})
 
 	for _, serv := range services {
-
 		what, ip := serv.HostType()
 
 		switch what {
@@ -97,7 +96,6 @@ func AAAA(ctx context.Context, b ServiceBackend, zone string, state request.Requ
 	dup := make(map[string]struct{})
 
 	for _, serv := range services {
-
 		what, ip := serv.HostType()
 
 		switch what {
@@ -344,7 +342,6 @@ func CNAME(ctx context.Context, b ServiceBackend, zone string, state request.Req
 
 // TXT returns TXT records from Backend or an error.
 func TXT(ctx context.Context, b ServiceBackend, zone string, state request.Request, previousRecords []dns.RR, opt Options) (records []dns.RR, truncated bool, err error) {
-
 	services, err := b.Services(ctx, state, false, opt)
 	if err != nil {
 		return nil, false, err
@@ -353,7 +350,6 @@ func TXT(ctx context.Context, b ServiceBackend, zone string, state request.Reque
 	dup := make(map[string]struct{})
 
 	for _, serv := range services {
-
 		what, _ := serv.HostType()
 
 		switch what {
@@ -405,7 +401,6 @@ func TXT(ctx context.Context, b ServiceBackend, zone string, state request.Reque
 				dup[serv.Text] = struct{}{}
 				records = append(records, serv.NewTXT(state.QName()))
 			}
-
 		}
 	}
 
@@ -507,7 +502,6 @@ func BackendError(ctx context.Context, b ServiceBackend, zone string, rcode int,
 }
 
 func newAddress(s msg.Service, name string, ip net.IP, what uint16) dns.RR {
-
 	hdr := dns.RR_Header{Name: name, Rrtype: what, Class: dns.ClassINET, Ttl: s.TTL}
 
 	if what == dns.TypeA {

plugin/bind/setup.go

@@ -12,7 +12,6 @@ import (
 )
 
 func setup(c *caddy.Controller) error {
-
 	config := dnsserver.GetConfig(c)
 	// addresses will be consolidated over all BIND directives available in that BlocServer
 	all := []string{}

plugin/cache/cache_test.go

@@ -609,7 +609,7 @@ func TestCacheWildcardMetadata(t *testing.T) {
 	ctx = metadata.ContextWithMetadata(context.TODO())
 	w = dnstest.NewRecorder(&test.ResponseWriter{})
 
-	c.ServeDNS(ctx, &test.ResponseWriter{}, req)
+	c.ServeDNS(ctx, w, req)
 	f := metadata.ValueFunc(ctx, "zone/wildcard")
 	if f == nil {
 		t.Fatal("expected metadata func for wildcard response retrieved from cache, got nil")

plugin/chaos/setup.go

@@ -30,7 +30,7 @@ func parse(c *caddy.Controller) (string, []string, error) {
 	chaosVersion = caddy.AppName + "-" + caddy.AppVersion
 	version := ""
 
-	for c.Next() {
+	if c.Next() {
 		args := c.RemainingArgs()
 		if len(args) == 0 {
 			return trim(chaosVersion), Owners, nil

plugin/clouddns/clouddns.go

@@ -204,7 +204,6 @@ func (h *CloudDNS) updateZones(ctx context.Context) error {
 				(*z[i]).z = newZ
 				h.zMu.Unlock()
 			}
-
 		}(zName, z)
 	}
 	// Collect errors (if any). This will also sync on all zones updates

plugin/clouddns/clouddns_test.go

@@ -152,7 +152,6 @@ func TestCloudDNS(t *testing.T) {
 
 			m.Authoritative = true
 			rcode = dns.RcodeSuccess
-
 		}
 
 		m.SetRcode(r, rcode)

plugin/clouddns/setup.go

@@ -81,16 +81,19 @@ func setup(c *caddy.Controller) error {
 		ctx, cancel := context.WithCancel(context.Background())
 		client, err := f(ctx, opt)
 		if err != nil {
+			cancel()
 			return err
 		}
 
 		h, err := New(ctx, client, keys, up)
 		if err != nil {
+			cancel()
 			return plugin.Error("clouddns", c.Errf("failed to create plugin: %v", err))
 		}
 		h.Fall = fall
 
 		if err := h.Run(ctx); err != nil {
+			cancel()
 			return plugin.Error("clouddns", c.Errf("failed to initialize plugin: %v", err))
 		}
 

plugin/debug/pcap_test.go

@@ -32,7 +32,7 @@ func TestNoDebug(t *testing.T) {
 	}
 }
 
-func ExampleLogHexdump() {
+func ExampleHexdump() {
 	buf, _ := msg().Pack()
 	h := hexdump(buf)
 	fmt.Println(string(h))