*: fix all comment-related golint warnings

Some of this code is going to be moved to SDK library, so it's important.

Signed-off-by: Roman Khimov <roman@nspcc.ru>

app.go

@@ -27,14 +27,17 @@ type (
 		webDone      chan struct{}
 	}
 
+	// App is an interface for the main gateway function.
 	App interface {
 		Wait()
 		Serve(context.Context)
 	}
 
+	// Option is an application option.
 	Option func(a *app)
 )
 
+// WithLogger returns Option to set a specific logger.
 func WithLogger(l *zap.Logger) Option {
 	return func(a *app) {
 		if l == nil {
@@ -44,6 +47,7 @@ func WithLogger(l *zap.Logger) Option {
 	}
 }
 
+// WithConfig returns Option to use specific Viper configuration.
 func WithConfig(c *viper.Viper) Option {
 	return func(a *app) {
 		if c == nil {

connections/pool.go

@@ -15,6 +15,7 @@ import (
 	"google.golang.org/grpc/keepalive"
 )
 
+// PoolBuilderOptions contains options used to build connection pool.
 type PoolBuilderOptions struct {
 	Key                     *ecdsa.PrivateKey
 	NodeConnectionTimeout   time.Duration
@@ -28,17 +29,21 @@ type PoolBuilderOptions struct {
 	connections             []*grpc.ClientConn
 }
 
+// PoolBuilder is an interim structure used to collect node addresses/weights and
+// build connection pool subsequently.
 type PoolBuilder struct {
 	addresses []string
 	weights   []float64
 }
 
+// AddNode adds address/weight pair to node PoolBuilder list.
 func (pb *PoolBuilder) AddNode(address string, weight float64) *PoolBuilder {
 	pb.addresses = append(pb.addresses, address)
 	pb.weights = append(pb.weights, weight)
 	return pb
 }
 
+// Build creates new pool based on current PoolBuilder state and options.
 func (pb *PoolBuilder) Build(ctx context.Context, options *PoolBuilderOptions) (Pool, error) {
 	if len(pb.addresses) == 0 {
 		return nil, errors.New("no NeoFS peers configured")
@@ -75,6 +80,7 @@ func (pb *PoolBuilder) Build(ctx context.Context, options *PoolBuilderOptions) (
 	return new(ctx, options)
 }
 
+// Pool is an interface providing connection artifacts on request.
 type Pool interface {
 	ConnectionArtifacts() (client.Client, *token.SessionToken, error)
 }

connections/sampler.go

@@ -2,13 +2,17 @@ package connections
 
 import "math/rand"
 
-// See Vose's Alias Method (https://www.keithschwarz.com/darts-dice-coins/).
+// Sampler implements weighted random number generation using Vose's Alias
+// Method (https://www.keithschwarz.com/darts-dice-coins/).
 type Sampler struct {
 	randomGenerator *rand.Rand
 	probabilities   []float64
 	alias           []int
 }
 
+// NewSampler creates new Sampler with a given set of probabilities using
+// given source of randomness. Created Sampler will produce numbers from
+// 0 to len(probabilities).
 func NewSampler(probabilities []float64, source rand.Source) *Sampler {
 	sampler := &Sampler{}
 	var (
@@ -53,6 +57,7 @@ func NewSampler(probabilities []float64, source rand.Source) *Sampler {
 	return sampler
 }
 
+// Next returns the next (not so) random number from Sampler.
 func (g *Sampler) Next() int {
 	n := len(g.alias)
 	i := g.randomGenerator.Intn(n)

downloader/download.go

@@ -165,11 +165,13 @@ func (o objectIDs) Slice() []string {
 	return res
 }
 
+// Downloader is a download request handler.
 type Downloader struct {
 	log   *zap.Logger
 	plant neofs.ClientPlant
 }
 
+// New creates an instance of Downloader using specified options.
 func New(ctx context.Context, log *zap.Logger, plant neofs.ClientPlant) (*Downloader, error) {
 	var err error
 	d := &Downloader{log: log, plant: plant}
@@ -187,6 +189,7 @@ func (d *Downloader) newRequest(ctx *fasthttp.RequestCtx, log *zap.Logger) *requ
 	}
 }
 
+// DownloadByAddress handles download requests using simple cid/oid format.
 func (d *Downloader) DownloadByAddress(c *fasthttp.RequestCtx) {
 	var (
 		err     error
@@ -214,6 +217,7 @@ func (d *Downloader) DownloadByAddress(c *fasthttp.RequestCtx) {
 	d.newRequest(c, log).receiveFile(getOpts)
 }
 
+// DownloadByAttribute handles attribute-based download requests.
 func (d *Downloader) DownloadByAttribute(c *fasthttp.RequestCtx) {
 	var (
 		err     error

global/context.go

@@ -12,6 +12,8 @@ var (
 	globalContextOnce sync.Once
 )
 
+// Context returns global context with initialized INT, TERM and HUP signal
+// handlers set to notify this context.
 func Context() context.Context {
 	globalContextOnce.Do(func() {
 		globalContext, _ = signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM, syscall.SIGHUP)

logger/grpc.go

@@ -12,12 +12,15 @@ type (
 		log *zap.SugaredLogger
 	}
 
+	// Logger includes grpclog.LoggerV2 interface with an additional
+	// Println method.
 	Logger interface {
 		grpclog.LoggerV2
 		Println(v ...interface{})
 	}
 )
 
+// GRPC wraps given zap.Logger into grpclog.LoggerV2+ interface.
 func GRPC(l *zap.Logger) Logger {
 	log := l.WithOptions(
 		// skip gRPCLog + zapLogger in caller
@@ -29,32 +32,47 @@ func GRPC(l *zap.Logger) Logger {
 	}
 }
 
+// Info implements grpclog.LoggerV2.
 func (z *zapLogger) Info(args ...interface{}) { z.log.Info(args...) }
 
+// Infoln implements grpclog.LoggerV2.
 func (z *zapLogger) Infoln(args ...interface{}) { z.log.Info(args...) }
 
+// Infof implements grpclog.LoggerV2.
 func (z *zapLogger) Infof(format string, args ...interface{}) { z.log.Infof(format, args...) }
 
+// Println allows to print a line with info severity.
 func (z *zapLogger) Println(args ...interface{}) { z.log.Info(args...) }
 
+// Printf implements grpclog.LoggerV2.
 func (z *zapLogger) Printf(format string, args ...interface{}) { z.log.Infof(format, args...) }
 
+// Warning implements grpclog.LoggerV2.
 func (z *zapLogger) Warning(args ...interface{}) { z.log.Warn(args...) }
 
+// Warningln implements grpclog.LoggerV2.
 func (z *zapLogger) Warningln(args ...interface{}) { z.log.Warn(args...) }
 
+// Warningf implements grpclog.LoggerV2.
 func (z *zapLogger) Warningf(format string, args ...interface{}) { z.log.Warnf(format, args...) }
 
+// Error implements grpclog.LoggerV2.
 func (z *zapLogger) Error(args ...interface{}) { z.log.Error(args...) }
 
+// Errorln implements grpclog.LoggerV2.
 func (z *zapLogger) Errorln(args ...interface{}) { z.log.Error(args...) }
 
+// Errorf implements grpclog.LoggerV2.
 func (z *zapLogger) Errorf(format string, args ...interface{}) { z.log.Errorf(format, args...) }
 
+// Fatal implements grpclog.LoggerV2.
 func (z *zapLogger) Fatal(args ...interface{}) { z.log.Fatal(args...) }
 
+// Fatalln implements grpclog.LoggerV2.
 func (z *zapLogger) Fatalln(args ...interface{}) { z.log.Fatal(args...) }
 
+// Fatalf implements grpclog.LoggerV2.
 func (z *zapLogger) Fatalf(format string, args ...interface{}) { z.log.Fatalf(format, args...) }
 
+// V implements grpclog.LoggerV2.
 func (z *zapLogger) V(int) bool { return z.Enabled(zapcore.DebugLevel) }

logger/option.go

@@ -2,22 +2,32 @@ package logger
 
 import "go.uber.org/zap"
 
+// WithSamplingInitial returns Option that sets sampling initial parameter.
 func WithSamplingInitial(v int) Option { return func(o *options) { o.SamplingInitial = v } }
 
+// WithSamplingThereafter returns Option that sets sampling thereafter parameter.
 func WithSamplingThereafter(v int) Option { return func(o *options) { o.SamplingThereafter = v } }
 
+// WithFormat returns Option that sets format parameter.
 func WithFormat(v string) Option { return func(o *options) { o.Format = v } }
 
+// WithLevel returns Option that sets Level parameter.
 func WithLevel(v string) Option { return func(o *options) { o.Level = v } }
 
+// WithTraceLevel returns Option that sets trace level parameter.
 func WithTraceLevel(v string) Option { return func(o *options) { o.TraceLevel = v } }
 
+// WithoutDisclaimer returns Option that disables disclaimer.
 func WithoutDisclaimer() Option { return func(o *options) { o.NoDisclaimer = true } }
 
+// WithoutCaller returns Option that disables caller printing.
 func WithoutCaller() Option { return func(o *options) { o.NoCaller = true } }
 
+// WithAppName returns Option that sets application name.
 func WithAppName(v string) Option { return func(o *options) { o.AppName = v } }
 
+// WithAppVersion returns Option that sets application version.
 func WithAppVersion(v string) Option { return func(o *options) { o.AppVersion = v } }
 
+// WithZapOptions returns Option that sets zap logger options.
 func WithZapOptions(opts ...zap.Option) Option { return func(o *options) { o.Options = opts } }

logger/zap.go

@@ -8,6 +8,7 @@ import (
 )
 
 type (
+	// Option represents logger option setter.
 	Option func(o *options)
 
 	options struct {
@@ -77,6 +78,8 @@ func defaults() *options {
 	}
 }
 
+// New returns new zap.Logger using all options specified and stdout used
+// for output.
 func New(opts ...Option) (*zap.Logger, error) {
 	o := defaults()
 	c := zap.NewProductionConfig()

misc.go

@@ -1,8 +1,12 @@
 package main
 
+// Prefix is a prefix used for environment variables containing gateway
+// configuration.
 const Prefix = "HTTP_GW"
 
 var (
+	// Build is a timestamp set during gateway build.
 	Build = "now"
+	// Version is gateway version.
 	Version = "dev"
 )

neofs/client-plant.go

@@ -13,12 +13,14 @@ import (
 	"github.com/nspcc-dev/neofs-http-gate/connections"
 )
 
+// BaseOptions represents basic NeoFS request options.
 type BaseOptions struct {
 	Client       client.Client
 	SessionToken *token.SessionToken
 	BearerToken  *token.BearerToken
 }
 
+// PutOptions represents NeoFS Put request options.
 type PutOptions struct {
 	BaseOptions
 	Attributes  []*object.Attribute
@@ -27,12 +29,14 @@ type PutOptions struct {
 	Reader      io.Reader
 }
 
+// GetOptions represents NeoFS Get request options.
 type GetOptions struct {
 	BaseOptions
 	ObjectAddress *object.Address
 	Writer        io.Writer
 }
 
+// SearchOptions represents NeoFS Search request options.
 type SearchOptions struct {
 	BaseOptions
 	ContainerID *container.ID
@@ -42,11 +46,13 @@ type SearchOptions struct {
 	}
 }
 
+// DeleteOptions represents NeoFS Delete request options.
 type DeleteOptions struct {
 	BaseOptions
 	ObjectAddress *object.Address
 }
 
+// ObjectClient wraps basic NeoFS requests.
 type ObjectClient interface {
 	Put(context.Context, *PutOptions) (*object.Address, error)
 	Get(context.Context, *GetOptions) (*object.Object, error)
@@ -54,6 +60,8 @@ type ObjectClient interface {
 	Delete(context.Context, *DeleteOptions) error
 }
 
+// ClientPlant provides connections to NeoFS nodes from pool and allows to
+// get local owner ID.
 type ClientPlant interface {
 	ConnectionArtifacts() (client.Client, *token.SessionToken, error)
 	Object() ObjectClient
@@ -71,10 +79,12 @@ type neofsClientPlant struct {
 	pool    connections.Pool
 }
 
+// ConnectionArtifacts returns connection from pool.
 func (cp *neofsClientPlant) ConnectionArtifacts() (client.Client, *token.SessionToken, error) {
 	return cp.pool.ConnectionArtifacts()
 }
 
+// Object returns ObjectClient instance from plant.
 func (cp *neofsClientPlant) Object() ObjectClient {
 	return &neofsObjectClient{
 		key:  cp.key,
@@ -82,14 +92,17 @@ func (cp *neofsClientPlant) Object() ObjectClient {
 	}
 }
 
+// OwnerID returns plant's owner ID.
 func (cp *neofsClientPlant) OwnerID() *owner.ID {
 	return cp.ownerID
 }
 
+// NewClientPlant creates new ClientPlant from given context, pool and credentials.
 func NewClientPlant(ctx context.Context, pool connections.Pool, creds Credentials) (ClientPlant, error) {
 	return &neofsClientPlant{key: creds.PrivateKey(), ownerID: creds.Owner(), pool: pool}, nil
 }
 
+// Put does NeoFS Put request, returning new object address if successful.
 func (oc *neofsObjectClient) Put(ctx context.Context, options *PutOptions) (*object.Address, error) {
 	var (
 		err      error
@@ -117,6 +130,7 @@ func (oc *neofsObjectClient) Put(ctx context.Context, options *PutOptions) (*obj
 	return address, nil
 }
 
+// Get does NeoFS Get request, returning an object received if successful.
 func (oc *neofsObjectClient) Get(ctx context.Context, options *GetOptions) (*object.Object, error) {
 	var (
 		err error
@@ -134,6 +148,7 @@ func (oc *neofsObjectClient) Get(ctx context.Context, options *GetOptions) (*obj
 	return obj, err
 }
 
+// Search does NeoFS Search request, returning object IDs if successful.
 func (oc *neofsObjectClient) Search(ctx context.Context, options *SearchOptions) ([]*object.ID, error) {
 	sfs := object.NewSearchFilters()
 	sfs.AddRootFilter()
@@ -149,6 +164,7 @@ func (oc *neofsObjectClient) Search(ctx context.Context, options *SearchOptions)
 	)
 }
 
+// Delete deletes NeoFS object.
 func (oc *neofsObjectClient) Delete(ctx context.Context, options *DeleteOptions) error {
 	ops := new(client.DeleteObjectParams).WithAddress(options.ObjectAddress)
 	err := options.Client.DeleteObject(

neofs/credentials.go

@@ -24,8 +24,8 @@ type (
 	}
 )
 
-// New creates an instance of Credentials through string representation of secret.
-//     It allows passing WIF, path, hex-encoded and others.
+// NewCredentials creates an instance of Credentials through string
+// representation of secret. It allows passing WIF, path, hex-encoded and others.
 func NewCredentials(secret string) (Credentials, error) {
 	key, err := crypto.LoadPrivateKey(secret)
 	if err != nil {

tokens/bearer-token.go

@@ -26,6 +26,7 @@ const (
 // 	return
 // }
 
+// BearerTokenFromHeader extracts bearer token from Authorization request header.
 func BearerTokenFromHeader(h *fasthttp.RequestHeader) []byte {
 	auth := h.Peek(fasthttp.HeaderAuthorization)
 	if auth == nil || !bytes.HasPrefix(auth, []byte(bearerTokenHdr)) {
@@ -37,6 +38,7 @@ func BearerTokenFromHeader(h *fasthttp.RequestHeader) []byte {
 	return auth
 }
 
+// BearerTokenFromCookie extracts bearer token from cookies.
 func BearerTokenFromCookie(h *fasthttp.RequestHeader) []byte {
 	auth := h.Cookie(bearerTokenHdr)
 	if len(auth) == 0 {
@@ -46,6 +48,8 @@ func BearerTokenFromCookie(h *fasthttp.RequestHeader) []byte {
 	return auth
 }
 
+// StoreBearerToken extracts bearer token from header or cookie and stores
+// it in the request context.
 func StoreBearerToken(ctx *fasthttp.RequestCtx) error {
 	tkn, err := fetchBearerToken(ctx)
 	if err != nil {
@@ -56,6 +60,8 @@ func StoreBearerToken(ctx *fasthttp.RequestCtx) error {
 	return nil
 }
 
+// LoadBearerToken returns bearer token stored in context given (if it's
+// present there).
 func LoadBearerToken(ctx context.Context) (*token.BearerToken, error) {
 	if tkn, ok := ctx.Value(bearerTokenKey).(*token.BearerToken); ok && tkn != nil {
 		return tkn, nil

uploader/multipart.go

@@ -7,6 +7,8 @@ import (
 	"go.uber.org/zap"
 )
 
+// MultipartFile provides standard ReadCloser interface and also allows one to
+// get file name, it's used for multipart uploads.
 type MultipartFile interface {
 	io.ReadCloser
 	FileName() string

uploader/upload.go

@@ -29,16 +29,20 @@ var putOptionsPool = sync.Pool{
 	},
 }
 
+// Uploader is an upload request handler.
 type Uploader struct {
 	log                    *zap.Logger
 	plant                  neofs.ClientPlant
 	enableDefaultTimestamp bool
 }
 
+// New creates a new Uploader using specified logger, connection pool and
+// other options.
 func New(log *zap.Logger, plant neofs.ClientPlant, enableDefaultTimestamp bool) *Uploader {
 	return &Uploader{log, plant, enableDefaultTimestamp}
 }
 
+// Upload handles multipart upload request.
 func (u *Uploader) Upload(c *fasthttp.RequestCtx) {
 	var (
 		err        error