[#20] get/head: Add tracing support

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

app.go

@@ -10,7 +10,9 @@ import (
 	"strconv"
 	"sync"
 	"syscall"
+	"time"
 
+	"git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/pkg/tracing"
 	"git.frostfs.info/TrueCloudLab/frostfs-http-gw/downloader"
 	"git.frostfs.info/TrueCloudLab/frostfs-http-gw/metrics"
 	"git.frostfs.info/TrueCloudLab/frostfs-http-gw/resolver"
@@ -166,6 +168,7 @@ func newApp(ctx context.Context, opt ...Option) App {
 	a.initAppSettings()
 	a.initResolver()
 	a.initMetrics()
+	a.initTracing(ctx)
 
 	return a
 }
@@ -375,7 +378,7 @@ LOOP:
 		case <-ctx.Done():
 			break LOOP
 		case <-sigs:
-			a.configReload()
+			a.configReload(ctx)
 		}
 	}
 
@@ -383,11 +386,22 @@ LOOP:
 
 	a.metrics.Shutdown()
 	a.stopServices()
+	a.shutdownTracing()
 
 	close(a.webDone)
 }
 
-func (a *app) configReload() {
+func (a *app) shutdownTracing() {
+	const tracingShutdownTimeout = 5 * time.Second
+	shdnCtx, cancel := context.WithTimeout(context.Background(), tracingShutdownTimeout)
+	defer cancel()
+
+	if err := tracing.Shutdown(shdnCtx); err != nil {
+		a.log.Warn("failed to shutdown tracing", zap.Error(err))
+	}
+}
+
+func (a *app) configReload(ctx context.Context) {
 	a.log.Info("SIGHUP config reload started")
 	if !a.cfg.IsSet(cmdConfig) && !a.cfg.IsSet(cmdConfigDir) {
 		a.log.Warn("failed to reload config because it's missed")
@@ -418,6 +432,7 @@ func (a *app) configReload() {
 	a.updateSettings()
 
 	a.metrics.SetEnabled(a.cfg.GetBool(cfgPrometheusEnabled))
+	a.initTracing(ctx)
 	a.setHealthStatus()
 
 	a.log.Info("SIGHUP config reload completed")
@@ -549,3 +564,25 @@ func (a *app) serverIndex(address string) int {
 	}
 	return -1
 }
+
+func (a *app) initTracing(ctx context.Context) {
+	instanceID := ""
+	if len(a.servers) > 0 {
+		instanceID = a.servers[0].Address()
+	}
+	cfg := tracing.Config{
+		Enabled:    a.cfg.GetBool(cfgTracingEnabled),
+		Exporter:   tracing.Exporter(a.cfg.GetString(cfgTracingExporter)),
+		Endpoint:   a.cfg.GetString(cfgTracingEndpoint),
+		Service:    "frostfs-http-gw",
+		InstanceID: instanceID,
+		Version:    Version,
+	}
+	updated, err := tracing.Setup(ctx, cfg)
+	if err != nil {
+		a.log.Warn("failed to initialize tracing", zap.Error(err))
+	}
+	if updated {
+		a.log.Info("tracing config updated")
+	}
+}

config/config.env

@@ -92,3 +92,7 @@ HTTP_GW_POOL_ERROR_THRESHOLD=100
 
 # Enable zip compression to download files by common prefix.
 HTTP_GW_ZIP_COMPRESSION=false
+
+HTTP_GW_TRACING_ENABLED=true
+HTTP_GW_TRACING_ENDPOINT="localhost:4317"
+HTTP_GW_TRACING_EXPORTER="otlp_grpc"

config/config.yaml

@@ -9,6 +9,10 @@ pprof:
 prometheus:
   enabled: false # Enable metrics.
   address: localhost:8084
+tracing:
+  enabled: true
+  exporter: "otlp_grpc"
+  endpoint: "localhost:4317"
 
 logger:
   level: debug # Log level.

docs/gate-configuration.md

@@ -52,6 +52,7 @@ $ cat http.log
 | `zip`           | [ZIP configuration](#zip-section)                     |
 | `pprof`         | [Pprof configuration](#pprof-section)                 |
 | `prometheus`    | [Prometheus configuration](#prometheus-section)       |
+| `tracing`       | [Tracing configuration](#tracing-section)       |
 
 
 # General section
@@ -238,3 +239,20 @@ prometheus:
 |-----------|----------|---------------|------------------|-----------------------------------------|
 | `enabled` | `bool`   | yes           | `false`          | Flag to enable the service.             |
 | `address` | `string` | yes           | `localhost:8084` | Address that service listener binds to. |
+
+# `tracing` section
+
+Contains configuration for the `tracing` service.
+
+```yaml
+tracing:
+  enabled: true
+  exporter: "otlp_grpc"
+  endpoint: "localhost:4317"
+```
+
+| Parameter  | Type     | SIGHUP reload | Default value    | Description                                                   |
+|------------|----------|---------------|------------------|---------------------------------------------------------------|
+| `enabled`  | `bool`   | yes           | `false`          | Flag to enable the tracing.                                   |
+| `exporter` | `string` | yes           |                  | Trace collector type (`stdout` or `otlp_grpc` are supported). |
+| `endpoint` | `string` | yes           |                  | Address of collector endpoint for OTLP exporters.             |

downloader/download.go

@@ -27,14 +27,15 @@ import (
 	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
 	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/pool"
 	"github.com/valyala/fasthttp"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/trace"
 	"go.uber.org/atomic"
 	"go.uber.org/zap"
 )
 
 type request struct {
 	*fasthttp.RequestCtx
-	appCtx context.Context
+	log *zap.Logger
-	log    *zap.Logger
 }
 
 func isValidToken(s string) bool {
@@ -88,40 +89,40 @@ func readContentType(maxSize uint64, rInit func(uint64) (io.Reader, error)) (str
 	return http.DetectContentType(buf), buf, err // to not lose io.EOF
 }
 
-func (r request) receiveFile(clnt *pool.Pool, objectAddress oid.Address) {
+func receiveFile(ctx context.Context, req request, clnt *pool.Pool, objectAddress oid.Address) {
 	var (
 		err      error
 		dis      = "inline"
 		start    = time.Now()
 		filename string
 	)
-	if err = tokens.StoreBearerToken(r.RequestCtx); err != nil {
+	if err = tokens.StoreBearerToken(req.RequestCtx); err != nil {
-		r.log.Error("could not fetch and store bearer token", zap.Error(err))
+		req.log.Error("could not fetch and store bearer token", zap.Error(err))
-		response.Error(r.RequestCtx, "could not fetch and store bearer token: "+err.Error(), fasthttp.StatusBadRequest)
+		response.Error(req.RequestCtx, "could not fetch and store bearer token: "+err.Error(), fasthttp.StatusBadRequest)
 		return
 	}
 
 	var prm pool.PrmObjectGet
 	prm.SetAddress(objectAddress)
-	if btoken := bearerToken(r.RequestCtx); btoken != nil {
+	if btoken := bearerToken(req.RequestCtx); btoken != nil {
 		prm.UseBearer(*btoken)
 	}
 
-	rObj, err := clnt.GetObject(r.appCtx, prm)
+	rObj, err := clnt.GetObject(ctx, prm)
 	if err != nil {
-		r.handleFrostFSErr(err, start)
+		req.handleFrostFSErr(err, start)
 		return
 	}
 
 	// we can't close reader in this function, so how to do it?
 
-	if r.Request.URI().QueryArgs().GetBool("download") {
+	if req.Request.URI().QueryArgs().GetBool("download") {
 		dis = "attachment"
 	}
 
 	payloadSize := rObj.Header.PayloadSize()
 
-	r.Response.Header.Set(fasthttp.HeaderContentLength, strconv.FormatUint(payloadSize, 10))
+	req.Response.Header.Set(fasthttp.HeaderContentLength, strconv.FormatUint(payloadSize, 10))
 	var contentType string
 	for _, attr := range rObj.Header.Attributes() {
 		key := attr.Key()
@@ -132,27 +133,27 @@ func (r request) receiveFile(clnt *pool.Pool, objectAddress oid.Address) {
 
 		key = utils.BackwardTransformIfSystem(key)
 
-		r.Response.Header.Set(utils.UserAttributeHeaderPrefix+key, val)
+		req.Response.Header.Set(utils.UserAttributeHeaderPrefix+key, val)
 		switch key {
 		case object.AttributeFileName:
 			filename = val
 		case object.AttributeTimestamp:
 			value, err := strconv.ParseInt(val, 10, 64)
 			if err != nil {
-				r.log.Info("couldn't parse creation date",
+				req.log.Info("couldn't parse creation date",
 					zap.String("key", key),
 					zap.String("val", val),
 					zap.Error(err))
 				continue
 			}
-			r.Response.Header.Set(fasthttp.HeaderLastModified,
+			req.Response.Header.Set(fasthttp.HeaderLastModified,
 				time.Unix(value, 0).UTC().Format(http.TimeFormat))
 		case object.AttributeContentType:
 			contentType = val
 		}
 	}
 
-	idsToResponse(&r.Response, &rObj.Header)
+	idsToResponse(&req.Response, &rObj.Header)
 
 	if len(contentType) == 0 {
 		// determine the Content-Type from the payload head
@@ -162,8 +163,8 @@ func (r request) receiveFile(clnt *pool.Pool, objectAddress oid.Address) {
 			return rObj.Payload, nil
 		})
 		if err != nil && err != io.EOF {
-			r.log.Error("could not detect Content-Type from payload", zap.Error(err))
+			req.log.Error("could not detect Content-Type from payload", zap.Error(err))
-			response.Error(r.RequestCtx, "could not detect Content-Type from payload: "+err.Error(), fasthttp.StatusBadRequest)
+			response.Error(req.RequestCtx, "could not detect Content-Type from payload: "+err.Error(), fasthttp.StatusBadRequest)
 			return
 		}
 
@@ -178,11 +179,11 @@ func (r request) receiveFile(clnt *pool.Pool, objectAddress oid.Address) {
 		// if it implements io.Closer and that's useful for us.
 		rObj.Payload = readCloser{headReader, rObj.Payload}
 	}
-	r.SetContentType(contentType)
+	req.SetContentType(contentType)
 
-	r.Response.Header.Set(fasthttp.HeaderContentDisposition, dis+"; filename="+path.Base(filename))
+	req.Response.Header.Set(fasthttp.HeaderContentDisposition, dis+"; filename="+path.Base(filename))
 
-	r.Response.SetBodyStream(rObj.Payload, int(payloadSize))
+	req.Response.SetBodyStream(rObj.Payload, int(payloadSize))
 }
 
 func bearerToken(ctx context.Context) *bearer.Token {
@@ -240,26 +241,35 @@ func New(ctx context.Context, params *utils.AppParams, settings *Settings) *Down
 func (d *Downloader) newRequest(ctx *fasthttp.RequestCtx, log *zap.Logger) *request {
 	return &request{
 		RequestCtx: ctx,
-		appCtx:     d.appCtx,
 		log:        log,
 	}
 }
 
 // DownloadByAddress handles download requests using simple cid/oid format.
 func (d *Downloader) DownloadByAddress(c *fasthttp.RequestCtx) {
-	d.byAddress(c, request.receiveFile)
+	d.byAddress(c, receiveFile)
 }
 
 // byAddress is a wrapper for function (e.g. request.headObject, request.receiveFile) that
 // prepares request and object address to it.
-func (d *Downloader) byAddress(c *fasthttp.RequestCtx, f func(request, *pool.Pool, oid.Address)) {
+func (d *Downloader) byAddress(c *fasthttp.RequestCtx, f func(context.Context, request, *pool.Pool, oid.Address)) {
 	var (
 		idCnr, _ = c.UserValue("cid").(string)
 		idObj, _ = c.UserValue("oid").(string)
 		log      = d.log.With(zap.String("cid", idCnr), zap.String("oid", idObj))
 	)
 
-	cnrID, err := utils.GetContainerID(d.appCtx, idCnr, d.containerResolver)
+	ctx, span := utils.StartHTTPServerSpan(d.appCtx, c, "GET Object",
+		trace.WithAttributes(
+			attribute.String("cid", idCnr),
+			attribute.String("oid", idObj),
+		))
+	defer func() {
+		utils.SetHTTPTraceInfo(ctx, span, c)
+		span.End()
+	}()
+
+	cnrID, err := utils.GetContainerID(ctx, idCnr, d.containerResolver)
 	if err != nil {
 		log.Error("wrong container id", zap.Error(err))
 		response.Error(c, "wrong container id", fasthttp.StatusBadRequest)
@@ -277,16 +287,16 @@ func (d *Downloader) byAddress(c *fasthttp.RequestCtx, f func(request, *pool.Poo
 	addr.SetContainer(*cnrID)
 	addr.SetObject(*objID)
 
-	f(*d.newRequest(c, log), d.pool, addr)
+	f(ctx, *d.newRequest(c, log), d.pool, addr)
 }
 
 // DownloadByAttribute handles attribute-based download requests.
 func (d *Downloader) DownloadByAttribute(c *fasthttp.RequestCtx) {
-	d.byAttribute(c, request.receiveFile)
+	d.byAttribute(c, receiveFile)
 }
 
 // byAttribute is a wrapper similar to byAddress.
-func (d *Downloader) byAttribute(c *fasthttp.RequestCtx, f func(request, *pool.Pool, oid.Address)) {
+func (d *Downloader) byAttribute(c *fasthttp.RequestCtx, f func(context.Context, request, *pool.Pool, oid.Address)) {
 	var (
 		scid, _ = c.UserValue("cid").(string)
 		key, _  = url.QueryUnescape(c.UserValue("attr_key").(string))
@@ -294,7 +304,18 @@ func (d *Downloader) byAttribute(c *fasthttp.RequestCtx, f func(request, *pool.P
 		log     = d.log.With(zap.String("cid", scid), zap.String("attr_key", key), zap.String("attr_val", val))
 	)
 
-	containerID, err := utils.GetContainerID(d.appCtx, scid, d.containerResolver)
+	ctx, span := utils.StartHTTPServerSpan(d.appCtx, c, "GET Object",
+		trace.WithAttributes(
+			attribute.String("attr_key", key),
+			attribute.String("attr_val", val),
+			attribute.String("cid", scid),
+		))
+	defer func() {
+		utils.SetHTTPTraceInfo(ctx, span, c)
+		span.End()
+	}()
+
+	containerID, err := utils.GetContainerID(ctx, scid, d.containerResolver)
 	if err != nil {
 		log.Error("wrong container id", zap.Error(err))
 		response.Error(c, "wrong container id", fasthttp.StatusBadRequest)
@@ -329,7 +350,7 @@ func (d *Downloader) byAttribute(c *fasthttp.RequestCtx, f func(request, *pool.P
 	addrObj.SetContainer(*containerID)
 	addrObj.SetObject(buf[0])
 
-	f(*d.newRequest(c, log), d.pool, addrObj)
+	f(ctx, *d.newRequest(c, log), d.pool, addrObj)
 }
 
 func (d *Downloader) search(c *fasthttp.RequestCtx, cid *cid.ID, key, val string, op object.SearchMatchType) (pool.ResObjectSearch, error) {

downloader/head.go

@@ -1,6 +1,7 @@
 package downloader
 
 import (
+	"context"
 	"io"
 	"net/http"
 	"strconv"
@@ -13,6 +14,8 @@ import (
 	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
 	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/pool"
 	"github.com/valyala/fasthttp"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/trace"
 	"go.uber.org/zap"
 )
 
@@ -25,15 +28,25 @@ const (
 	hdrContainerID = "X-Container-Id"
 )
 
-func (r request) headObject(clnt *pool.Pool, objectAddress oid.Address) {
+func headObject(ctx context.Context, req request, clnt *pool.Pool, objectAddress oid.Address) {
+	ctx, span := utils.StartHTTPServerSpan(ctx, req.RequestCtx, "HEAD Object",
+		trace.WithAttributes(
+			attribute.String("cid", objectAddress.Container().EncodeToString()),
+			attribute.String("oid", objectAddress.Object().EncodeToString()),
+		))
+	defer func() {
+		utils.SetHTTPTraceInfo(ctx, span, req.RequestCtx)
+		span.End()
+	}()
+
 	var start = time.Now()
-	if err := tokens.StoreBearerToken(r.RequestCtx); err != nil {
+	if err := tokens.StoreBearerToken(req.RequestCtx); err != nil {
-		r.log.Error("could not fetch and store bearer token", zap.Error(err))
+		req.log.Error("could not fetch and store bearer token", zap.Error(err))
-		response.Error(r.RequestCtx, "could not fetch and store bearer token", fasthttp.StatusBadRequest)
+		response.Error(req.RequestCtx, "could not fetch and store bearer token", fasthttp.StatusBadRequest)
 		return
 	}
 
-	btoken := bearerToken(r.RequestCtx)
+	btoken := bearerToken(req.RequestCtx)
 
 	var prm pool.PrmObjectHead
 	prm.SetAddress(objectAddress)
@@ -41,13 +54,13 @@ func (r request) headObject(clnt *pool.Pool, objectAddress oid.Address) {
 		prm.UseBearer(*btoken)
 	}
 
-	obj, err := clnt.HeadObject(r.appCtx, prm)
+	obj, err := clnt.HeadObject(ctx, prm)
 	if err != nil {
-		r.handleFrostFSErr(err, start)
+		req.handleFrostFSErr(err, start)
 		return
 	}
 
-	r.Response.Header.Set(fasthttp.HeaderContentLength, strconv.FormatUint(obj.PayloadSize(), 10))
+	req.Response.Header.Set(fasthttp.HeaderContentLength, strconv.FormatUint(obj.PayloadSize(), 10))
 	var contentType string
 	for _, attr := range obj.Attributes() {
 		key := attr.Key()
@@ -58,24 +71,24 @@ func (r request) headObject(clnt *pool.Pool, objectAddress oid.Address) {
 
 		key = utils.BackwardTransformIfSystem(key)
 
-		r.Response.Header.Set(utils.UserAttributeHeaderPrefix+key, val)
+		req.Response.Header.Set(utils.UserAttributeHeaderPrefix+key, val)
 		switch key {
 		case object.AttributeTimestamp:
 			value, err := strconv.ParseInt(val, 10, 64)
 			if err != nil {
-				r.log.Info("couldn't parse creation date",
+				req.log.Info("couldn't parse creation date",
 					zap.String("key", key),
 					zap.String("val", val),
 					zap.Error(err))
 				continue
 			}
-			r.Response.Header.Set(fasthttp.HeaderLastModified, time.Unix(value, 0).UTC().Format(http.TimeFormat))
+			req.Response.Header.Set(fasthttp.HeaderLastModified, time.Unix(value, 0).UTC().Format(http.TimeFormat))
 		case object.AttributeContentType:
 			contentType = val
 		}
 	}
 
-	idsToResponse(&r.Response, &obj)
+	idsToResponse(&req.Response, &obj)
 
 	if len(contentType) == 0 {
 		contentType, _, err = readContentType(obj.PayloadSize(), func(sz uint64) (io.Reader, error) {
@@ -86,18 +99,18 @@ func (r request) headObject(clnt *pool.Pool, objectAddress oid.Address) {
 				prmRange.UseBearer(*btoken)
 			}
 
-			resObj, err := clnt.ObjectRange(r.appCtx, prmRange)
+			resObj, err := clnt.ObjectRange(ctx, prmRange)
 			if err != nil {
 				return nil, err
 			}
 			return &resObj, nil
 		})
 		if err != nil && err != io.EOF {
-			r.handleFrostFSErr(err, start)
+			req.handleFrostFSErr(err, start)
 			return
 		}
 	}
-	r.SetContentType(contentType)
+	req.SetContentType(contentType)
 }
 
 func idsToResponse(resp *fasthttp.Response, obj *object.Object) {
@@ -110,10 +123,10 @@ func idsToResponse(resp *fasthttp.Response, obj *object.Object) {
 
 // HeadByAddress handles head requests using simple cid/oid format.
 func (d *Downloader) HeadByAddress(c *fasthttp.RequestCtx) {
-	d.byAddress(c, request.headObject)
+	d.byAddress(c, headObject)
 }
 
 // HeadByAttribute handles attribute-based head requests.
 func (d *Downloader) HeadByAttribute(c *fasthttp.RequestCtx) {
-	d.byAttribute(c, request.headObject)
+	d.byAttribute(c, headObject)
 }

go.mod

@@ -14,6 +14,8 @@ require (
 	github.com/stretchr/testify v1.8.2
 	github.com/testcontainers/testcontainers-go v0.13.0
 	github.com/valyala/fasthttp v1.34.0
+	go.opentelemetry.io/otel v1.14.0
+	go.opentelemetry.io/otel/trace v1.14.0
 	go.uber.org/atomic v1.10.0
 	go.uber.org/zap v1.24.0
 )
@@ -86,13 +88,11 @@ require (
 	github.com/urfave/cli v1.22.5 // indirect
 	github.com/valyala/bytebufferpool v1.0.0 // indirect
 	go.opencensus.io v0.24.0 // indirect
-	go.opentelemetry.io/otel v1.14.0 // indirect
 	go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.14.0 // indirect
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.14.0 // indirect
 	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.14.0 // indirect
 	go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.14.0 // indirect
 	go.opentelemetry.io/otel/sdk v1.14.0 // indirect
-	go.opentelemetry.io/otel/trace v1.14.0 // indirect
 	go.opentelemetry.io/proto/otlp v0.19.0 // indirect
 	go.uber.org/multierr v1.9.0 // indirect
 	golang.org/x/crypto v0.4.0 // indirect

settings.go

@@ -47,6 +47,11 @@ const (
 	cfgPprofEnabled      = "pprof.enabled"
 	cfgPprofAddress      = "pprof.address"
 
+	// Tracing ...
+	cfgTracingEnabled  = "tracing.enabled"
+	cfgTracingExporter = "tracing.exporter"
+	cfgTracingEndpoint = "tracing.endpoint"
+
 	// Pool config.
 	cfgConTimeout         = "connect_timeout"
 	cfgStreamTimeout      = "stream_timeout"

utils/tracing.go

@@ -0,0 +1,82 @@
+package utils
+
+import (
+	"context"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/pkg/tracing"
+	"github.com/valyala/fasthttp"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/codes"
+	semconv "go.opentelemetry.io/otel/semconv/v1.17.0"
+	"go.opentelemetry.io/otel/trace"
+)
+
+type httpCarrier struct {
+	r *fasthttp.RequestCtx
+}
+
+func (c *httpCarrier) Get(key string) string {
+	bytes := c.r.Request.Header.Peek(key)
+	if len(bytes) == 0 {
+		return ""
+	}
+	return string(bytes)
+}
+
+func (c *httpCarrier) Set(key string, value string) {
+	c.r.Response.Header.Set(key, value)
+}
+
+func (c *httpCarrier) Keys() []string {
+	dict := make(map[string]interface{})
+	c.r.Request.Header.VisitAll(
+		func(key, value []byte) {
+			dict[string(key)] = true
+		},
+	)
+	c.r.Response.Header.VisitAll(
+		func(key, value []byte) {
+			dict[string(key)] = true
+		},
+	)
+	result := make([]string, 0, len(dict))
+	for key := range dict {
+		result = append(result, key)
+	}
+	return result
+}
+
+func extractHTTPTraceInfo(ctx context.Context, req *fasthttp.RequestCtx) context.Context {
+	if req == nil {
+		return ctx
+	}
+	carrier := &httpCarrier{r: req}
+	return tracing.Propagator.Extract(ctx, carrier)
+}
+
+// SetHTTPTraceInfo saves trace headers to response.
+func SetHTTPTraceInfo(ctx context.Context, span trace.Span, req *fasthttp.RequestCtx) {
+	if req == nil {
+		return
+	}
+	if err := req.Err(); err != nil {
+		span.SetStatus(codes.Error, err.Error())
+	}
+	span.SetAttributes(
+		semconv.HTTPStatusCode(req.Response.StatusCode()),
+	)
+	carrier := &httpCarrier{r: req}
+	tracing.Propagator.Inject(ctx, carrier)
+}
+
+// StartHTTPServerSpan starts root HTTP server span.
+func StartHTTPServerSpan(ctx context.Context, req *fasthttp.RequestCtx, operationName string, opts ...trace.SpanStartOption) (context.Context, trace.Span) {
+	ctx = extractHTTPTraceInfo(ctx, req)
+	opts = append(opts, trace.WithAttributes(
+		attribute.String("http.client_address", req.RemoteAddr().String()),
+		attribute.String("http.path", string(req.Path())),
+		semconv.HTTPMethod(string(req.Method())),
+		semconv.RPCService("frostfs-http-gw"),
+	), trace.WithSpanKind(trace.SpanKindServer))
+	return tracing.StartSpanFromContext(ctx, operationName, opts...)
+}