You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: ghttp_middleware_tracing.go
    path of file: ./repos/gf/net/ghttp
    
    the code of the file until where you have to start completion: // Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.

package ghttp

import (
	"compress/gzip"
	"context"
	"fmt"
	"io"
	"net/http"
	"strings"

	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/codes"
	"go.opentelemetry.io/otel/propagation"
	"go.opentelemetry.io/otel/trace"

	"github.com/gogf/gf/v2"
	"github.com/gogf/gf/v2/errors/gerror"
	"github.com/gogf/gf/v2/internal/httputil"
	"github.com/gogf/gf/v2/internal/utils"
	"github.com/gogf/gf/v2/net/gtrace"
	"github.com/gogf/gf/v2/os/gctx"
	"github.com/gogf/gf/v2/text/gstr"
	"github.com/gogf/gf/v2/util/gconv"
)

const (
	tracingInstrumentName                       = "github.com/gogf/gf/v2/net/ghttp.Server"
	tracingEventHttp
    
func internalMiddlewareServerTracing(r *Request) {
	var (
		ctx = r.Context()
	)
	// Mark this request is handled by server tracing middleware,
	// to avoid repeated handling by the same middleware.
	if ctx.Value(tracingMiddlewareHandled) != nil {
		r.Middleware.Next()
		return
	}

	ctx = context.WithValue(ctx, tracingMiddlewareHandled, 1)
	var (
		span trace.Span
		tr   = otel.GetTracerProvider().Tracer(
			tracingInstrumentName,
			trace.WithInstrumentationVersion(gf.VERSION),
		)
	)
	ctx, span = tr.Start(
		otel.GetTextMapPropagator().Extract(
			ctx,
			propagation.HeaderCarrier(r.Header),
		),
		r.URL.Path,
		trace.WithSpanKind(trace.SpanKindServer),
	)
	defer span.End()

	span.SetAttributes(gtrace.CommonLabels()...)

	// Inject tracing context.
	r.SetCtx(ctx)

	// If it is now using a default trace provider, it then does no complex tracing jobs.
	if gtrace.IsUsingDefaultProvider() {
		r.Middleware.Next()
		return
	}

	// Request content logging.
	reqBodyContentBytes, err := io.ReadAll(r.Body)
	if err != nil {
		r.SetError(gerror.Wrap(err, `read request body failed`))
		span.SetStatus(codes.Error, fmt.Sprintf(`%+v`, err))
		return
	}
	r.Body = utils.NewReadCloser(reqBodyContentBytes, false)

	span.AddEvent(tracingEventHttpRequest, trace.WithAttributes(
		attribute.String(tracingEventHttpRequestUrl, r.URL.String()),
		attribute.String(tracingEventHttpRequestHeaders, gconv.String(httputil.HeaderToMap(r.Header))),
		attribute.String(tracingEventHttpRequestBaggage, gtrace.GetBaggageMap(ctx).String()),
		attribute.String(tracingEventHttpRequestBody, gstr.StrLimitRune(
			string(reqBodyContentBytes),
			gtrace.MaxContentLogSize(),
			"...",
		)),
	))

	// Continue executing.
	r.Middleware.Next()

	// parse after set route as span name
	if r.Router.Uri != defaultMiddlewarePattern || r.Router.RegNames != nil {
		span.SetName(r.Router.Uri)
	}

	// Error logging.
	if err = r.GetError(); err != nil {
		span.SetStatus(codes.Error, fmt.Sprintf(`%+v`, err))
	}
	// Response content logging.
	var resBodyContent = gstr.StrLimitRune(r.Response.BufferString(), gtrace.MaxContentLogSize(), "...")
	if gzipAccepted(r.Response.Header()) {
		reader, err := gzip.NewReader(strings.NewReader(r.Response.BufferString()))
		if err != nil {
			span.SetStatus(codes.Error, fmt.Sprintf(`read gzip response err:%+v`, err))
		}
		defer reader.Close()
		uncompressed, err := io.ReadAll(reader)
		if err != nil {
			span.SetStatus(codes.Error, fmt.Sprintf(`get uncompress value err:%+v`, err))
		}
		resBodyContent = gstr.StrLimitRune(string(uncompressed), gtrace.MaxContentLogSize(), "...")
	}

	span.AddEvent(tracingEventHttpResponse, trace.WithAttributes(
		attribute.String(tracingEventHttpResponseHeaders, gconv.String(httputil.HeaderToMap(r.Response.Header()))),
		attribute.String(tracingEventHttpResponseBody, resBodyContent),
	))
}