go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.43.0: Exporter.MarshalLog

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: verify otlptrace.Exporter.MarshalLog in pkg:golang/go.opentelemetry.io/otel/exporters/otlp/otlptrace@v1.43.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/go.opentelemetry.io/otel/exporters/otlp/otlptrace@v1.43.0
Demonstrate these symbols/APIs:
  - otlptrace.Exporter.MarshalLog

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

{"case":{"caseId":"case:sha256:cc4eb3f65041cc0c71a4ca88444d33a79247ded3356100664700bc558c642302","contract":["otlptrace.Exporter.MarshalLog returns structured logging metadata with Type and Client fields","otlptrace.Exporter.MarshalLog correctly preserves the configured otlptrace.Client instance","otlptrace.New and otlptrace.NewUnstarted create Exporters whose MarshalLog outputs otlptrace type identifier"],"goal":"verify otlptrace.Exporter.MarshalLog in pkg:golang/go.opentelemetry.io/otel/exporters/otlp/otlptrace@v1.43.0","kind":"HOW","packages":["pkg:golang/go.opentelemetry.io/otel/exporters/otlp/otlptrace@v1.43.0"],"schemaVersion":1,"symbols":["otlptrace.Exporter.MarshalLog"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","language":"go","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","packageManagerVersion":"1.26.6","runtime":"go","runtimeVersion":"1.26.6","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/go.opentelemetry.io/otel/exporters/otlp/otlptrace@v1.43.0"],"schemaVersion":1,"subject":"pkg:golang/go.opentelemetry.io/otel/exporters/otlp/otlptrace@v1.43.0","symbols":["otlptrace.Exporter.MarshalLog"],"verifierAdapter":"golang@1"}

package sample

import (
	"context"
	"fmt"

	"go.opentelemetry.io/otel/exporters/otlp/otlptrace"
)

// CreateExporter creates a new OTLP trace Exporter with the provided client.
func CreateExporter(ctx context.Context, client otlptrace.Client) (*otlptrace.Exporter, error) {
	if client == nil {
		return nil, fmt.Errorf("client cannot be nil")
	}
	return otlptrace.New(ctx, client)
}

// LogRepresentation extracts the structured log representation from an otlptrace Exporter using MarshalLog.
func LogRepresentation(exp *otlptrace.Exporter) any {
	if exp == nil {
		return nil
	}
	return exp.MarshalLog()
}

module sample

go 1.26.6

require (
	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.43.0
	go.opentelemetry.io/proto/otlp v1.10.0
)

require (
	github.com/cespare/xxhash/v2 v2.3.0 // indirect
	github.com/go-logr/logr v1.4.3 // indirect
	github.com/go-logr/stdr v1.2.2 // indirect
	github.com/google/uuid v1.6.0 // indirect
	go.opentelemetry.io/auto/sdk v1.2.1 // indirect
	go.opentelemetry.io/otel v1.43.0 // indirect
	go.opentelemetry.io/otel/metric v1.43.0 // indirect
	go.opentelemetry.io/otel/sdk v1.43.0 // indirect
	go.opentelemetry.io/otel/trace v1.43.0 // indirect
	golang.org/x/sys v0.42.0 // indirect
	google.golang.org/protobuf v1.36.11 // indirect
)

github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
github.com/go-logr/logr v1.4.3 h1:CjnDlHq8ikf6E492q6eKboGOC0T8CDaOvkHCIg8idEI=
github.com/go-logr/logr v1.4.3/go.mod h1:9T104GzyrTigFIr8wt5mBrctHMim0Nb2HLGrmQ40KvY=
github.com/go-logr/stdr v1.2.2 h1:hSWxHoqTgW2S2qGc0LTAI563KZ5YKYRhT3MFKZMbjag=
github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
go.opentelemetry.io/auto/sdk v1.2.1 h1:jXsnJ4Lmnqd11kwkBV2LgLoFMZKizbCi5fNZ/ipaZ64=
go.opentelemetry.io/auto/sdk v1.2.1/go.mod h1:KRTj+aOaElaLi+wW1kO/DZRXwkF4C5xPbEe3ZiIhN7Y=
go.opentelemetry.io/otel v1.43.0 h1:mYIM03dnh5zfN7HautFE4ieIig9amkNANT+xcVxAj9I=
go.opentelemetry.io/otel v1.43.0/go.mod h1:JuG+u74mvjvcm8vj8pI5XiHy1zDeoCS2LB1spIq7Ay0=
go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.43.0 h1:88Y4s2C8oTui1LGM6bTWkw0ICGcOLCAI5l6zsD1j20k=
go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.43.0/go.mod h1:Vl1/iaggsuRlrHf/hfPJPvVag77kKyvrLeD10kpMl+A=
go.opentelemetry.io/otel/metric v1.43.0 h1:d7638QeInOnuwOONPp4JAOGfbCEpYb+K6DVWvdxGzgM=
go.opentelemetry.io/otel/metric v1.43.0/go.mod h1:RDnPtIxvqlgO8GRW18W6Z/4P462ldprJtfxHxyKd2PY=
go.opentelemetry.io/otel/sdk v1.43.0 h1:pi5mE86i5rTeLXqoF/hhiBtUNcrAGHLKQdhg4h4V9Dg=
go.opentelemetry.io/otel/sdk v1.43.0/go.mod h1:P+IkVU3iWukmiit/Yf9AWvpyRDlUeBaRg6Y+C58QHzg=
go.opentelemetry.io/otel/sdk/metric v1.43.0 h1:S88dyqXjJkuBNLeMcVPRFXpRw2fuwdvfCGLEo89fDkw=
go.opentelemetry.io/otel/sdk/metric v1.43.0/go.mod h1:C/RJtwSEJ5hzTiUz5pXF1kILHStzb9zFlIEe85bhj6A=
go.opentelemetry.io/otel/trace v1.43.0 h1:BkNrHpup+4k4w+ZZ86CZoHHEkohws8AY+WTX09nk+3A=
go.opentelemetry.io/otel/trace v1.43.0/go.mod h1:/QJhyVBUUswCphDVxq+8mld+AvhXZLhe+8WVFxiFff0=
go.opentelemetry.io/proto/otlp v1.10.0 h1:IQRWgT5srOCYfiWnpqUYz9CVmbO8bFmKcwYxpuCSL2g=
go.opentelemetry.io/proto/otlp v1.10.0/go.mod h1:/CV4QoCR/S9yaPj8utp3lvQPoqMtxXdzn7ozvvozVqk=
go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
golang.org/x/sys v0.42.0 h1:omrd2nAlyT5ESRdCLYdm3+fMfNFE/+Rf4bDIQImRJeo=
golang.org/x/sys v0.42.0/go.mod h1:4GL1E5IUh+htKOUEOaiffhrAeqysfVGipDYzABqnCmw=
google.golang.org/protobuf v1.36.11 h1:fV6ZwhNocDyBLK0dj+fg8ektcVegBBuEolpbTQyBNVE=
google.golang.org/protobuf v1.36.11/go.mod h1:HTf+CrKn2C3g5S8VImy6tdcUvCska2kB7j23XfzDpco=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

{
  "schemaVersion": 1,
  "goal": "verify otlptrace.Exporter.MarshalLog in pkg:golang/go.opentelemetry.io/otel/exporters/otlp/otlptrace@v1.43.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/go.opentelemetry.io/otel/exporters/otlp/otlptrace@v1.43.0"
  ],
  "symbols": [
    "otlptrace.Exporter.MarshalLog"
  ]
}

package main

import (
	"context"
	"fmt"
	"os"
	"reflect"

	"sample"

	"go.opentelemetry.io/otel/exporters/otlp/otlptrace"
	tracepb "go.opentelemetry.io/proto/otlp/trace/v1"
)

type mockClient struct {
	started bool
	stopped bool
}

func (m *mockClient) Start(ctx context.Context) error {
	m.started = true
	return nil
}

func (m *mockClient) Stop(ctx context.Context) error {
	m.stopped = true
	return nil
}

func (m *mockClient) UploadTraces(ctx context.Context, protoSpans []*tracepb.ResourceSpans) error {
	return nil
}

func main() {
	ctx := context.Background()
	client := &mockClient{}

	// 1. Verify Exporter creation with otlptrace.New
	exp, err := sample.CreateExporter(ctx, client)
	if err != nil {
		fmt.Fprintf(os.Stderr, "Contract failure: failed to create exporter: %v\n", err)
		os.Exit(1)
	}
	if exp == nil {
		fmt.Fprintf(os.Stderr, "Contract failure: exporter is nil\n")
		os.Exit(1)
	}

	// 2. Verify otlptrace.Exporter.MarshalLog returns structured log metadata
	logData := sample.LogRepresentation(exp)
	if logData == nil {
		fmt.Fprintf(os.Stderr, "Contract failure: MarshalLog returned nil\n")
		os.Exit(1)
	}

	v := reflect.ValueOf(logData)
	if v.Kind() != reflect.Struct {
		fmt.Fprintf(os.Stderr, "Contract failure: expected struct return type, got %s\n", v.Kind())
		os.Exit(1)
	}

	typeField := v.FieldByName("Type")
	if !typeField.IsValid() || typeField.String() != "otlptrace" {
		fmt.Fprintf(os.Stderr, "Contract failure: expected Type 'otlptrace', got %v\n", typeField)
		os.Exit(1)
	}

	clientField := v.FieldByName("Client")
	if !clientField.IsValid() || clientField.IsNil() {
		fmt.Fprintf(os.Stderr, "Contract failure: expected non-nil Client in MarshalLog\n")
		os.Exit(1)
	}

	if clientField.Interface() != client {
		fmt.Fprintf(os.Stderr, "Contract failure: client field does not match the configured client\n")
		os.Exit(1)
	}

	// 3. Verify unstarted Exporter MarshalLog
	unstartedExp := otlptrace.NewUnstarted(client)
	unstartedLogData := unstartedExp.MarshalLog()
	if unstartedLogData == nil {
		fmt.Fprintf(os.Stderr, "Contract failure: unstarted Exporter MarshalLog returned nil\n")
		os.Exit(1)
	}

	unstartedV := reflect.ValueOf(unstartedLogData)
	if unstartedV.FieldByName("Type").String() != "otlptrace" {
		fmt.Fprintf(os.Stderr, "Contract failure: unstarted Exporter Type mismatch\n")
		os.Exit(1)
	}

	// 4. Verify clean shutdown
	if err := exp.Shutdown(ctx); err != nil {
		fmt.Fprintf(os.Stderr, "Contract failure: failed to shutdown exporter: %v\n", err)
		os.Exit(1)
	}

	fmt.Println("All contract assertions passed successfully.")
}