fixed struct alignment && refactor linter (#369)

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1. Give a descriptive title to your PR.
2. Provide a description of your changes.
3. Make sure you have some relevant tests.
4. Put `closes #XXXX` in your comment to auto-close the issue that your PR fixes (if applicable).

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Reviewed-on: #369
Co-authored-by: Evstigneev Denis <danteevstigneev@yandex.ru>
Co-committed-by: Evstigneev Denis <danteevstigneev@yandex.ru>

util/dns/cache.go

@@ -43,7 +43,7 @@ func NewNetDialer(parent DialFunc, opts ...Option) DialFunc {
 	if cache.opts.MaxCacheEntries == 0 {
 		cache.opts.MaxCacheEntries = DefaultMaxCacheEntries
 	}
-	return func(ctx context.Context, network, address string) (net.Conn, error) {
+	return func(_ context.Context, network, address string) (net.Conn, error) {
 		conn := &dnsConn{}
 		conn.roundTrip = cachingRoundTrip(&cache, network, address)
 		return conn, nil
@@ -132,12 +132,12 @@ func PreferIPV6(b bool) Option {
 }
 
 type cache struct {
-	sync.RWMutex
-
-	dial    DialFunc
 	entries map[string]cacheEntry
+	dial    DialFunc
 
 	opts Options
+
+	sync.RWMutex
 }
 
 type cacheEntry struct {
@@ -306,7 +306,7 @@ func getNameLen(msg string) int {
 	for i < len(msg) {
 		if msg[i] == 0 {
 			// end of name
-			i += 1
+			i++
 			break
 		}
 		if msg[i] >= 0xc0 {
@@ -336,8 +336,7 @@ func cachingRoundTrip(cache *cache, network, address string) roundTripper {
 		cache.opts.Meter.Counter(semconv.CacheRequestInflight, "type", "dns").Inc()
 		defer cache.opts.Meter.Counter(semconv.CacheRequestInflight, "type", "dns").Dec()
 		// check cache
-		if res := cache.get(req); res != "" {
-			cache.opts.Meter.Counter(semconv.CacheRequestTotal, "type", "dns", "method", "get", "status", "hit").Inc()
+		if res = cache.get(req); res != "" {
 			return res, nil
 		}
 		cache.opts.Meter.Counter(semconv.CacheRequestTotal, "type", "dns", "method", "get", "status", "miss").Inc()

util/dns/cache_test.go

@@ -8,15 +8,13 @@ import (
 func TestCache(t *testing.T) {
 	net.DefaultResolver = NewNetResolver(PreferIPV4(true))
 
-	addrs, err := net.LookupHost("unistack.org")
+	_, err := net.LookupHost("unistack.org")
 	if err != nil {
 		t.Fatal(err)
 	}
 
-	addrs, err = net.LookupHost("unistack.org")
+	_, err = net.LookupHost("unistack.org")
 	if err != nil {
 		t.Fatal(err)
 	}
-
-	_ = addrs
 }

util/dns/conn.go

@@ -11,12 +11,15 @@ import (
 )
 
 type dnsConn struct {
-	deadline  time.Time
 	ctx       context.Context
 	cancel    context.CancelFunc
 	roundTrip roundTripper
-	ibuf      bytes.Buffer
-	obuf      bytes.Buffer
+
+	deadline time.Time
+
+	ibuf bytes.Buffer
+	obuf bytes.Buffer
+
 	sync.Mutex
 }
 
@@ -81,7 +84,7 @@ func (c *dnsConn) SetReadDeadline(t time.Time) error {
 	return nil
 }
 
-func (c *dnsConn) SetWriteDeadline(t time.Time) error {
+func (c *dnsConn) SetWriteDeadline(_ time.Time) error {
 	// writes do not timeout
 	return nil
 }
@@ -159,23 +162,22 @@ func readMessage(c net.Conn) (string, error) {
 			return "", err
 		}
 		return string(b[:n]), nil
-	} else {
-		var sz [2]byte
-		_, err := io.ReadFull(c, sz[:])
-		if err != nil {
-			return "", err
-		}
-
-		size := int64(sz[0])<<8 | int64(sz[1])
-
-		var str strings.Builder
-		_, err = io.CopyN(&str, c, size)
-		if err == io.EOF {
-			return "", io.ErrUnexpectedEOF
-		}
-		if err != nil {
-			return "", err
-		}
-		return str.String(), nil
 	}
+	var sz [2]byte
+	_, err := io.ReadFull(c, sz[:])
+	if err != nil {
+		return "", err
+	}
+
+	size := int64(sz[0])<<8 | int64(sz[1])
+
+	var str strings.Builder
+	_, err = io.CopyN(&str, c, size)
+	if err == io.EOF {
+		return "", io.ErrUnexpectedEOF
+	}
+	if err != nil {
+		return "", err
+	}
+	return str.String(), nil
 }

util/grpc/tracer.go

@@ -71,7 +71,7 @@ func (h *serverHandler) HandleRPC(ctx context.Context, rs stats.RPCStats) {
 }
 
 // TagConn can attach some information to the given context.
-func (h *serverHandler) TagConn(ctx context.Context, info *stats.ConnTagInfo) context.Context {
+func (h *serverHandler) TagConn(ctx context.Context, _ *stats.ConnTagInfo) context.Context {
 	if span, ok := tracer.SpanFromContext(ctx); ok {
 		attrs := peerAttr(peerFromCtx(ctx))
 		span.AddLabels(attrs...)
@@ -80,7 +80,7 @@ func (h *serverHandler) TagConn(ctx context.Context, info *stats.ConnTagInfo) co
 }
 
 // HandleConn processes the Conn stats.
-func (h *serverHandler) HandleConn(ctx context.Context, info stats.ConnStats) {
+func (h *serverHandler) HandleConn(_ context.Context, _ stats.ConnStats) {
 }
 
 type clientHandler struct {

util/http/trie.go

@@ -665,12 +665,12 @@ func patParamKeys(pattern string) ([]string, error) {
 // longestPrefix finds the length of the shared prefix
 // of two strings
 func longestPrefix(k1, k2 string) int {
-	max := len(k1)
-	if l := len(k2); l < max {
-		max = l
+	maxLen := len(k1)
+	if l := len(k2); l < maxLen {
+		maxLen = l
 	}
 	var i int
-	for i = 0; i < max; i++ {
+	for i = 0; i < maxLen; i++ {
 		if k1[i] != k2[i] {
 			break
 		}

util/jitter/random.go

@@ -14,7 +14,7 @@ func Random(d time.Duration) time.Duration {
 	return time.Duration(v)
 }
 
-func RandomInterval(min, max time.Duration) time.Duration {
+func RandomInterval(minTime, maxTime time.Duration) time.Duration {
 	var rng rand.Rand
-	return time.Duration(rng.Int63n(max.Nanoseconds()-min.Nanoseconds())+min.Nanoseconds()) * time.Nanosecond
+	return time.Duration(rng.Int63n(maxTime.Nanoseconds()-minTime.Nanoseconds())+minTime.Nanoseconds()) * time.Nanosecond
 }

util/jitter/ticker.go

@@ -23,12 +23,12 @@ type Ticker struct {
 // NewTickerContext returns a pointer to an initialized instance of the Ticker.
 // It works like NewTicker except that it has ability to close via context.
 // Also it works fine with context.WithTimeout to handle max time to run ticker.
-func NewTickerContext(ctx context.Context, min, max time.Duration) *Ticker {
+func NewTickerContext(ctx context.Context, minTime, maxTime time.Duration) *Ticker {
 	ticker := &Ticker{
 		C:    make(chan time.Time),
 		done: make(chan chan struct{}),
-		min:  min.Nanoseconds(),
-		max:  max.Nanoseconds(),
+		min:  minTime.Nanoseconds(),
+		max:  maxTime.Nanoseconds(),
 		ctx:  ctx,
 	}
 	go ticker.run()
@@ -38,12 +38,12 @@ func NewTickerContext(ctx context.Context, min, max time.Duration) *Ticker {
 // NewTicker returns a pointer to an initialized instance of the Ticker.
 // Min and max are durations of the shortest and longest allowed
 // ticks. Ticker will run in a goroutine until explicitly stopped.
-func NewTicker(min, max time.Duration) *Ticker {
+func NewTicker(minTime, maxTime time.Duration) *Ticker {
 	ticker := &Ticker{
 		C:    make(chan time.Time),
 		done: make(chan chan struct{}),
-		min:  min.Nanoseconds(),
-		max:  max.Nanoseconds(),
+		min:  minTime.Nanoseconds(),
+		max:  maxTime.Nanoseconds(),
 		ctx:  context.Background(),
 	}
 	go ticker.run()

util/jitter/ticker_test.go

@@ -31,26 +31,26 @@ loop:
 func TestTicker(t *testing.T) {
 	t.Parallel()
 
-	min := time.Duration(10)
-	max := time.Duration(20)
+	minTime := time.Duration(10)
+	maxTime := time.Duration(20)
 
 	// tick can take a little longer since we're not adjusting it to account for
 	// processing.
 	precision := time.Duration(4)
 
-	rt := NewTicker(min*time.Millisecond, max*time.Millisecond)
+	rt := NewTicker(minTime*time.Millisecond, maxTime*time.Millisecond)
 	for i := 0; i < 5; i++ {
 		t0 := time.Now()
 		t1 := <-rt.C
 		td := t1.Sub(t0)
-		if td < min*time.Millisecond {
+		if td < minTime*time.Millisecond {
 			t.Fatalf("tick was shorter than expected: %s", td)
-		} else if td > (max+precision)*time.Millisecond {
+		} else if td > (maxTime+precision)*time.Millisecond {
 			t.Fatalf("tick was longer than expected: %s", td)
 		}
 	}
 	rt.Stop()
-	time.Sleep((max + precision) * time.Millisecond)
+	time.Sleep((maxTime + precision) * time.Millisecond)
 	select {
 	case v, ok := <-rt.C:
 		if ok || !v.IsZero() {

util/net/net.go

@@ -48,19 +48,19 @@ func Listen(addr string, fn func(string) (net.Listener, error)) (net.Listener, e
 	// we have a port range
 
 	// extract min port
-	min, err := strconv.Atoi(prange[0])
+	minPort, err := strconv.Atoi(prange[0])
 	if err != nil {
 		return nil, errors.New("unable to extract port range")
 	}
 
 	// extract max port
-	max, err := strconv.Atoi(prange[1])
+	maxPort, err := strconv.Atoi(prange[1])
 	if err != nil {
 		return nil, errors.New("unable to extract port range")
 	}
 
 	// range the ports
-	for port := min; port <= max; port++ {
+	for port := minPort; port <= maxPort; port++ {
 		// try bind to host:port
 		ln, err := fn(HostPort(host, port))
 		if err == nil {
@@ -68,7 +68,7 @@ func Listen(addr string, fn func(string) (net.Listener, error)) (net.Listener, e
 		}
 
 		// hit max port
-		if port == max {
+		if port == maxPort {
 			return nil, err
 		}
 	}

util/reflect/path.go

@@ -155,7 +155,7 @@ func indexFunction(v reflect.Value) func(i int) reflect.Value {
 			return v.MapIndex(keys[i])
 		}
 	}
-	return func(i int) reflect.Value { return reflect.Value{} }
+	return func(_ int) reflect.Value { return reflect.Value{} }
 }
 
 func mergeValue(values []reflect.Value) reflect.Value {

util/reflect/reflect_test.go

@@ -130,16 +130,16 @@ func TestMergeString(t *testing.T) {
 
 func TestMergeNested(t *testing.T) {
 	type CallReqNested struct {
+		Nested     *CallReqNested `json:"nested2"`
 		StringArgs []string       `json:"string_args"`
 		Uint64Args []uint64       `json:"uint64_args"`
-		Nested     *CallReqNested `json:"nested2"`
 	}
 
 	type CallReq struct {
+		Nested *CallReqNested `json:"nested"`
 		Name   string         `json:"name"`
 		Req    string         `json:"req"`
 		Arg2   int            `json:"arg2"`
-		Nested *CallReqNested `json:"nested"`
 	}
 
 	dst := &CallReq{

util/register/util.go

@@ -109,12 +109,11 @@ func Merge(olist []*register.Service, nlist []*register.Service) []*register.Ser
 				seen = true
 				srv = append(srv, sp)
 				break
-			} else {
-				sp := &register.Service{}
-				// make copy
-				*sp = *o
-				srv = append(srv, sp)
 			}
+			sp := &register.Service{}
+			// make copy
+			*sp = *o
+			srv = append(srv, sp)
 		}
 		if !seen {
 			srv = append(srv, Copy([]*register.Service{n})...)
@@ -153,14 +152,14 @@ func Remove(old, del []*register.Service) []*register.Service {
 
 // WaitService using register wait for service to appear with min/max interval for check and optional timeout.
 // Timeout can be 0 to wait infinitive.
-func WaitService(ctx context.Context, reg register.Register, name string, min time.Duration, max time.Duration, timeout time.Duration, opts ...register.LookupOption) error {
+func WaitService(ctx context.Context, reg register.Register, name string, minTime time.Duration, maxTime time.Duration, timeout time.Duration, opts ...register.LookupOption) error {
 	if timeout > 0 {
 		var cancel context.CancelFunc
 		ctx, cancel = context.WithTimeout(ctx, timeout)
 		defer cancel()
 	}
 
-	ticker := jitter.NewTickerContext(ctx, min, max)
+	ticker := jitter.NewTickerContext(ctx, minTime, maxTime)
 	defer ticker.Stop()
 
 	for {

util/ring/buffer.go

@@ -10,10 +10,11 @@ import (
 
 // Buffer is ring buffer
 type Buffer struct {
-	sync.RWMutex
 	streams map[string]*Stream
 	vals    []*Entry
 	size    int
+
+	sync.RWMutex
 }
 
 // Entry is ring buffer data entry

util/socket/pool.go

@@ -6,8 +6,8 @@ import (
 
 // Pool holds the socket pool
 type Pool struct {
-	sync.RWMutex
 	pool map[string]*Socket
+	sync.RWMutex
 }
 
 // Get socket from pool

util/stream/stream.go

@@ -20,10 +20,11 @@ type Stream interface {
 }
 
 type stream struct {
-	sync.RWMutex
 	Stream
 	err     error
 	request *request
+
+	sync.RWMutex
 }
 
 type request struct {

util/structfs/metadata_digitalocean.go

@@ -10,11 +10,18 @@ import (
 type DigitalOceanMetadata struct {
 	Metadata struct {
 		V1 struct {
-			DropletID  int64    `json:"droplet_id"`
-			Hostname   string   `json:"hostname"`
-			VendorData string   `json:"vendor_data"`
+			Features map[string]interface{} `json:"features"`
+
+			Hostname   string `json:"hostname"`
+			VendorData string `json:"vendor_data"`
+			Region     string `json:"region"`
+
 			PublicKeys []string `json:"public_keys"`
-			Region     string   `json:"region"`
+
+			DNS struct {
+				Nameservers []string `json:"nameservers"`
+			} `json:"dns"`
+
 			Interfaces struct {
 				Private []struct {
 					IPv4 struct {
@@ -31,24 +38,23 @@ type DigitalOceanMetadata struct {
 						Netmask string `json:"netmask"`
 						Gateway string `json:"gateway"`
 					} `json:"ipv4"`
-					IPv6 struct {
-						Address string `json:"ip_address"`
-						CIDR    int    `json:"cidr"`
-						Gateway string `json:"gateway"`
-					} `json:"ipv6"`
 					Mac  string `json:"mac"`
 					Type string `json:"type"`
+					IPv6 struct {
+						Address string `json:"ip_address"`
+						Gateway string `json:"gateway"`
+						CIDR    int    `json:"cidr"`
+					} `json:"ipv6"`
 				} `json:"public"`
 			} `json:"interfaces"`
+
+			DropletID int64 `json:"droplet_id"`
+
 			FloatingIP struct {
 				IPv4 struct {
 					Active bool `json:"active"`
 				} `json:"ipv4"`
 			} `json:"floating_ip"`
-			DNS struct {
-				Nameservers []string `json:"nameservers"`
-			} `json:"dns"`
-			Features map[string]interface{} `json:"features"`
 		} `json:"v1"`
 	} `json:"metadata"`
 }

util/structfs/metadata_ec2.go

@@ -2,29 +2,29 @@ package structfs
 
 type EC2Metadata struct {
 	Latest struct {
+		Userdata string `json:"user-data"`
 		Metadata struct {
-			AMIID              int      `json:"ami-id"`
-			AMILaunchIndex     int      `json:"ami-launch-index"`
-			AMIManifestPath    string   `json:"ami-manifest-path"`
-			AncestorAMIIDs     []int    `json:"ancestor-ami-ids"`
-			BlockDeviceMapping []string `json:"block-device-mapping"`
-			InstanceID         int      `json:"instance-id"`
-			InstanceType       string   `json:"instance-type"`
-			LocalHostname      string   `json:"local-hostname"`
-			LocalIPv4          string   `json:"local-ipv4"`
-			KernelID           int      `json:"kernel-id"`
-			Placement          string   `json:"placement"`
-			AvailabilityZone   string   `json:"availability-zone"`
-			ProductCodes       string   `json:"product-codes"`
-			PublicHostname     string   `json:"public-hostname"`
-			PublicIPv4         string   `json:"public-ipv4"`
-			PublicKeys         []struct {
+			AMIManifestPath  string `json:"ami-manifest-path"`
+			InstanceType     string `json:"instance-type"`
+			LocalHostname    string `json:"local-hostname"`
+			LocalIPv4        string `json:"local-ipv4"`
+			Placement        string `json:"placement"`
+			AvailabilityZone string `json:"availability-zone"`
+			ProductCodes     string `json:"product-codes"`
+			PublicHostname   string `json:"public-hostname"`
+			PublicIPv4       string `json:"public-ipv4"`
+			PublicKeys       []struct {
 				Key []string `json:"-"`
 			} `json:"public-keys"`
-			RamdiskID      int      `json:"ramdisk-id"`
-			ReservationID  int      `json:"reservation-id"`
-			SecurityGroups []string `json:"security-groups"`
+			AncestorAMIIDs     []int    `json:"ancestor-ami-ids"`
+			BlockDeviceMapping []string `json:"block-device-mapping"`
+			SecurityGroups     []string `json:"security-groups"`
+			RamdiskID          int      `json:"ramdisk-id"`
+			ReservationID      int      `json:"reservation-id"`
+			AMIID              int      `json:"ami-id"`
+			AMILaunchIndex     int      `json:"ami-launch-index"`
+			KernelID           int      `json:"kernel-id"`
+			InstanceID         int      `json:"instance-id"`
 		} `json:"meta-data"`
-		Userdata string `json:"user-data"`
 	} `json:"latest"`
 }

util/structfs/structfs.go

@@ -35,22 +35,22 @@ func (fs *fs) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 
 type fs struct {
+	modtime time.Time
 	iface   interface{}
 	tag     string
-	modtime time.Time
 }
 
 type file struct {
-	name    string
-	offset  int64
-	data    []byte
 	modtime time.Time
+	name    string
+	data    []byte
+	offset  int64
 }
 
 type fileInfo struct {
+	modtime time.Time
 	name    string
 	size    int64
-	modtime time.Time
 }
 
 func (fi *fileInfo) Sys() interface{} {
@@ -105,7 +105,7 @@ func (f *file) Read(b []byte) (int, error) {
 	return n, err
 }
 
-func (f *file) Readdir(count int) ([]os.FileInfo, error) {
+func (f *file) Readdir(_ int) ([]os.FileInfo, error) {
 	return nil, nil
 }
 

util/structfs/structfs_test.go

@@ -93,7 +93,7 @@ func TestAll(t *testing.T) {
 		in  string
 		out string
 	}{
-		{"http://127.0.0.1:8080/metadata/v1/", "droplet_id\nhostname\nvendor_data\npublic_keys\nregion\ninterfaces\nfloating_ip\ndns\nfeatures"},
+		{"http://127.0.0.1:8080/metadata/v1/", "features\nhostname\nvendor_data\nregion\npublic_keys\ndns\ninterfaces\ndroplet_id\nfloating_ip"},
 		{"http://127.0.0.1:8080/metadata/v1/droplet_id", "2756294"},
 		{"http://127.0.0.1:8080/metadata/v1/dns/", "nameservers"},
 		{"http://127.0.0.1:8080/metadata/v1/dns/nameservers", "2001:4860:4860::8844\n2001:4860:4860::8888\n8.8.8.8"},

util/test/test.go

@@ -78,8 +78,8 @@ var (
 			for _, se := range st.Details() {
 				switch ne := se.(type) {
 				case proto.Message:
-					buf, err := testCodec.Marshal(ne)
-					if err != nil {
+					var buf []byte
+					if buf, err = testCodec.Marshal(ne); err != nil {
 						return fmt.Errorf("failed to marshal err: %w", err)
 					}
 					if err = testCodec.Unmarshal(buf, &testMap); err != nil {
@@ -438,10 +438,10 @@ func Run(ctx context.Context, c client.Client, m sqlmock.Sqlmock, dir string, ex
 }
 
 type Case struct {
-	dbfiles []string
 	reqfile string
 	rspfile string
 	errfile string
+	dbfiles []string
 }
 
 func GetCases(dir string, exts []string) ([]Case, error) {

util/text/text.go

@@ -1,6 +1,5 @@
 package text
 
-
 func DetectEncoding(text string) map[string]int {
 	charsets := map[string]int{
 		"UTF-8":      0,
@@ -19,7 +18,7 @@ func DetectEncoding(text string) map[string]int {
 	utfupper := 5
 	lowercase := 3
 	uppercase := 1
-	last_simb := 0
+	lastSimb := 0
 
 	for a := 0; a < len(text); a++ {
 		char := int(text[a])
@@ -30,10 +29,10 @@ func DetectEncoding(text string) map[string]int {
 		}
 
 		// UTF-8
-		if (last_simb == 208) && ((char > 143 && char < 176) || char == 129) {
+		if (lastSimb == 208) && ((char > 143 && char < 176) || char == 129) {
 			charsets["UTF-8"] += (utfupper * 2)
 		}
-		if ((last_simb == 208) && ((char > 175 && char < 192) || char == 145)) || (last_simb == 209 && char > 127 && char < 144) {
+		if ((lastSimb == 208) && ((char > 175 && char < 192) || char == 145)) || (lastSimb == 209 && char > 127 && char < 144) {
 			charsets["UTF-8"] += (utflower * 2)
 		}
 
@@ -77,7 +76,7 @@ func DetectEncoding(text string) map[string]int {
 			charsets["MAC"] += uppercase
 		}
 
-	  last_simb = char
+		lastSimb = char
 	}
 
 	return charsets

util/time/duration.go

@@ -2,7 +2,6 @@ package time
 
 import (
 	"encoding/json"
-	"errors"
 	"fmt"
 	"strconv"
 	"time"
@@ -14,7 +13,7 @@ type Duration int64
 
 func ParseDuration(s string) (time.Duration, error) {
 	if s == "" {
-		return 0, errors.New(`time: invalid duration "` + s + `"`)
+		return 0, fmt.Errorf(`time: invalid duration "%s"`, s)
 	}
 
 	var p int
@@ -27,21 +26,21 @@ loop:
 		case 'h':
 			d, err := strconv.Atoi(s[p:i])
 			if err != nil {
-				return 0, errors.New("time: invalid duration " + s)
+				return 0, fmt.Errorf(`time: invalid duration "%s"`, s)
 			}
 			hours += d
 			p = i + 1
 		case 'd':
 			d, err := strconv.Atoi(s[p:i])
 			if err != nil {
-				return 0, errors.New("time: invalid duration " + s)
+				return 0, fmt.Errorf(`time: invalid duration "%s"`, s)
 			}
 			hours += d * 24
 			p = i + 1
 		case 'y':
 			n, err := strconv.Atoi(s[p:i])
 			if err != nil {
-				return 0, errors.New("time: invalid duration " + s)
+				return 0, fmt.Errorf(`time: invalid duration "%s"`, s)
 			}
 			var d int
 			for j := n - 1; j >= 0; j-- {