go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.43.0: New

# OpenTelemetry Go stdouttrace.New Semantics

## Search Known Solution Result
A search for `pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0` returned `NO_SAFE_MATCH`. This sample provides clean-room verification for `stdouttrace.New` and exporter configuration options.

## Pinned Release
- `go.opentelemetry.io/otel/exporters/stdout/stdouttrace`: `v1.43.0`

## Observed Behaviour
1. **Default Initialization**: `stdouttrace.New()` without options constructs a valid `*stdouttrace.Exporter` and returns nil error.
2. **Custom Writer**: `stdouttrace.WithWriter(w)` directs span JSON output to the provided `io.Writer`.
3. **Pretty Printing**: `stdouttrace.WithPrettyPrint()` formats serialized span JSON with indentation and newlines.
4. **Timestamp Suppression**: `stdouttrace.WithoutTimestamps()` suppresses timestamps in exported span records.
5. **Exporter Lifecycle**: `exp.Shutdown(ctx)` shuts down the exporter cleanly.

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 stdouttrace.New in pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0
Demonstrate these symbols/APIs:
  - stdouttrace.New
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

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:sha256:883cfeae863a38f65795d130a9d41f5dc73035acbf6b6673751e52574f6556c5","constraints":{"executionContext":"go"},"contract":["stdouttrace.New constructs a valid Exporter with default options and returns nil error","stdouttrace.New with stdouttrace.WithWriter directs exported span JSON to the specified writer","stdouttrace.New with stdouttrace.WithPrettyPrint formats serialized span output with indents and newlines","stdouttrace.New with stdouttrace.WithoutTimestamps suppresses timestamps on exported span records","Exporter.Shutdown flushes pending data and releases resources without error"],"goal":"verify stdouttrace.New in pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0","kind":"HOW","packages":["pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0"],"schemaVersion":1,"symbols":["stdouttrace.New"]},"contractCommand":["go","test","./..."],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","executionContext":"go","language":"go","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"gomod","runtime":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0"],"schemaVersion":1,"subject":"pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0","symbols":["stdouttrace.New"],"verifierAdapter":"golang@1"}

module example.com/stdouttrace-demo

go 1.26.6

require (
	go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.43.0
	go.opentelemetry.io/otel/sdk v1.43.0
)

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/trace v1.43.0 // indirect
	golang.org/x/sys v0.42.0 // 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/stdout/stdouttrace v1.43.0 h1:mS47AX77OtFfKG4vtp+84kuGSFZHTyxtXIN269vChY0=
go.opentelemetry.io/otel/exporters/stdout/stdouttrace v1.43.0/go.mod h1:PJnsC41lAGncJlPUniSwM81gc80GkgWJWr3cu2nKEtU=
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.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=
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 stdouttrace.New in pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/go.opentelemetry.io/otel/exporters/stdout/stdouttrace@v1.43.0"
  ],
  "symbols": [
    "stdouttrace.New"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

package main

import (
	"bytes"
	"context"
	"encoding/json"
	"strings"
	"testing"

	"go.opentelemetry.io/otel/exporters/stdout/stdouttrace"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
)

func TestNewDefaultExporter(t *testing.T) {
	exp, err := stdouttrace.New()
	if err != nil {
		t.Fatalf("stdouttrace.New() failed: %v", err)
	}
	if exp == nil {
		t.Fatalf("expected non-nil Exporter")
	}
	ctx := context.Background()
	if err := exp.Shutdown(ctx); err != nil {
		t.Fatalf("exp.Shutdown() failed: %v", err)
	}
}

func TestNewWithWriterAndExportSpans(t *testing.T) {
	var buf bytes.Buffer
	exp, err := stdouttrace.New(stdouttrace.WithWriter(&buf))
	if err != nil {
		t.Fatalf("stdouttrace.New(WithWriter) failed: %v", err)
	}
	defer exp.Shutdown(context.Background())

	tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exp))
	defer tp.Shutdown(context.Background())

	tracer := tp.Tracer("test-tracer")
	ctx := context.Background()
	_, span := tracer.Start(ctx, "operation-one")
	span.End()

	if err := tp.ForceFlush(ctx); err != nil {
		t.Fatalf("tp.ForceFlush failed: %v", err)
	}

	output := buf.String()
	if !strings.Contains(output, "operation-one") {
		t.Fatalf("expected output to contain span name 'operation-one', got: %s", output)
	}

	var raw map[string]interface{}
	if err := json.Unmarshal(buf.Bytes(), &raw); err != nil {
		t.Fatalf("expected output to be valid JSON: %v, raw output: %s", err, output)
	}
	if raw["Name"] != "operation-one" {
		t.Fatalf("expected Name to be 'operation-one', got %v", raw["Name"])
	}
}

func TestNewWithPrettyPrint(t *testing.T) {
	var buf bytes.Buffer
	exp, err := stdouttrace.New(
		stdouttrace.WithWriter(&buf),
		stdouttrace.WithPrettyPrint(),
	)
	if err != nil {
		t.Fatalf("stdouttrace.New(WithPrettyPrint) failed: %v", err)
	}
	defer exp.Shutdown(context.Background())

	tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exp))
	tracer := tp.Tracer("test-tracer")
	_, span := tracer.Start(context.Background(), "pretty-span")
	span.End()
	_ = tp.ForceFlush(context.Background())
	_ = tp.Shutdown(context.Background())

	output := buf.String()
	if !strings.Contains(output, "\n") || (!strings.Contains(output, "\t") && !strings.Contains(output, "  ")) {
		t.Fatalf("expected formatted JSON with indentation and newlines, got: %s", output)
	}
	if !strings.Contains(output, "pretty-span") {
		t.Fatalf("expected output to contain span name 'pretty-span', got: %s", output)
	}
}

func TestNewWithoutTimestamps(t *testing.T) {
	var buf bytes.Buffer
	exp, err := stdouttrace.New(
		stdouttrace.WithWriter(&buf),
		stdouttrace.WithoutTimestamps(),
	)
	if err != nil {
		t.Fatalf("stdouttrace.New(WithoutTimestamps) failed: %v", err)
	}
	defer exp.Shutdown(context.Background())

	tp := sdktrace.NewTracerProvider(sdktrace.WithSyncer(exp))
	tracer := tp.Tracer("test-tracer")
	_, span := tracer.Start(context.Background(), "no-timestamp-span")
	span.End()
	_ = tp.ForceFlush(context.Background())
	_ = tp.Shutdown(context.Background())

	var raw map[string]interface{}
	if err := json.Unmarshal(buf.Bytes(), &raw); err != nil {
		t.Fatalf("failed to unmarshal JSON: %v, raw output: %s", err, buf.String())
	}
	if raw["Name"] != "no-timestamp-span" {
		t.Fatalf("expected span name 'no-timestamp-span', got %v", raw["Name"])
	}
	if startTime, exists := raw["StartTime"]; exists && startTime != nil && startTime != "" && startTime != "0001-01-01T00:00:00Z" {
		t.Fatalf("expected StartTime to be zero/omitted with WithoutTimestamps, got %v", startTime)
	}
}

func TestExporterShutdown(t *testing.T) {
	var buf bytes.Buffer
	exp, err := stdouttrace.New(stdouttrace.WithWriter(&buf))
	if err != nil {
		t.Fatalf("stdouttrace.New failed: %v", err)
	}

	ctx := context.Background()
	if err := exp.Shutdown(ctx); err != nil {
		t.Fatalf("first exp.Shutdown failed: %v", err)
	}
	// Calling Shutdown again should succeed
	if err := exp.Shutdown(ctx); err != nil {
		t.Fatalf("subsequent exp.Shutdown failed: %v", err)
	}
}