go.opentelemetry.io/otel/trace v1.37.0: SpanID

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 go.opentelemetry.io/otel/trace.SpanID in pkg:golang/go.opentelemetry.io/otel/trace@v1.37.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/go.opentelemetry.io/otel/trace@v1.37.0
Demonstrate these symbols/APIs:
  - go.opentelemetry.io/otel/trace.SpanID

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:f252475a5474d43b490e27600caa8e52fedac3a3b5c41b7740e8de1ee4bb4e9b","contract":["SpanIDFromHex creates a valid SpanID from a 16-character hexadecimal string.","SpanIDFromHex returns an error for invalid length or invalid hexadecimal characters.","SpanID zero value is invalid and produces a 16-character zero string.","SpanID preserves raw byte array values and formats correctly via String.","SpanID MarshalJSON outputs a valid quoted JSON hex string.","SpanID integrates with SpanContext to identify traces and spans."],"goal":"verify go.opentelemetry.io/otel/trace.SpanID in pkg:golang/go.opentelemetry.io/otel/trace@v1.37.0","kind":"HOW","packages":["pkg:golang/go.opentelemetry.io/otel/trace@v1.37.0"],"schemaVersion":1,"symbols":["go.opentelemetry.io/otel/trace.SpanID"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/go.opentelemetry.io/otel/trace@v1.37.0"],"schemaVersion":1,"subject":"pkg:golang/go.opentelemetry.io/otel/trace@v1.37.0","symbols":["go.opentelemetry.io/otel/trace.SpanID"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require go.opentelemetry.io/otel/trace v1.37.0

require go.opentelemetry.io/otel v1.37.0 // indirect

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/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
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 v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
go.opentelemetry.io/otel v1.37.0 h1:9zhNfelUvx0KBfu/gb+ZgeAfAgtWrfHJZcAqFC228wQ=
go.opentelemetry.io/otel v1.37.0/go.mod h1:ehE/umFRLnuLa/vSccNq9oS1ErUlkkK71gMcN34UG8I=
go.opentelemetry.io/otel/trace v1.37.0 h1:HLdcFNbRQBE2imdSEgm/kwqmQj1Or1l/7bW6mxVK7z4=
go.opentelemetry.io/otel/trace v1.37.0/go.mod h1:TlgrlQ+PtQO5XFerSPUYG0JSgGyryXewPGyayAWSBS0=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package main

import (
	"encoding/json"
	"fmt"

	"go.opentelemetry.io/otel/trace"
)

func main() {
	// 1. Create a SpanID from hex string
	hexStr := "4bf92f3577b34da6"
	spanID, err := trace.SpanIDFromHex(hexStr)
	if err != nil {
		panic(err)
	}
	fmt.Printf("SpanID: %s, IsValid: %t\n", spanID.String(), spanID.IsValid())

	// 2. Create SpanID from raw byte array
	raw := [8]byte{0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08}
	rawSpanID := trace.SpanID(raw)
	fmt.Printf("Raw SpanID: %s\n", rawSpanID.String())

	// 3. Marshal SpanID to JSON
	data, err := json.Marshal(spanID)
	if err != nil {
		panic(err)
	}
	fmt.Printf("JSON representation: %s\n", string(data))

	// 4. Integrate with SpanContext
	sc := trace.NewSpanContext(trace.SpanContextConfig{
		SpanID: spanID,
	})
	fmt.Printf("SpanContext SpanID: %s, HasSpanID: %t\n", sc.SpanID().String(), sc.HasSpanID())
}

{
  "schemaVersion": 1,
  "goal": "verify go.opentelemetry.io/otel/trace.SpanID in pkg:golang/go.opentelemetry.io/otel/trace@v1.37.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/go.opentelemetry.io/otel/trace@v1.37.0"
  ],
  "symbols": [
    "go.opentelemetry.io/otel/trace.SpanID"
  ]
}

package main

import (
	"fmt"
	"os"

	"go.opentelemetry.io/otel/trace"
)

func main() {
	// Assertion 1: SpanIDFromHex creates a valid SpanID from a 16-character hexadecimal string.
	hexStr := "4bf92f3577b34da6"
	spanID, err := trace.SpanIDFromHex(hexStr)
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: SpanIDFromHex returned error: %v\n", err)
		os.Exit(1)
	}
	if !spanID.IsValid() {
		fmt.Fprintf(os.Stderr, "FAIL: expected spanID to be valid\n")
		os.Exit(1)
	}
	if spanID.String() != hexStr {
		fmt.Fprintf(os.Stderr, "FAIL: expected String() to be '%s', got '%s'\n", hexStr, spanID.String())
		os.Exit(1)
	}

	// Assertion 2: SpanIDFromHex returns an error for invalid length or invalid hexadecimal characters.
	if _, err := trace.SpanIDFromHex("1234"); err == nil {
		fmt.Fprintf(os.Stderr, "FAIL: expected error for short hex string\n")
		os.Exit(1)
	}
	if _, err := trace.SpanIDFromHex("4bf92f3577b34da678"); err == nil {
		fmt.Fprintf(os.Stderr, "FAIL: expected error for long hex string\n")
		os.Exit(1)
	}
	if _, err := trace.SpanIDFromHex("4bf92f3577b34dzz"); err == nil {
		fmt.Fprintf(os.Stderr, "FAIL: expected error for non-hex characters\n")
		os.Exit(1)
	}

	// Assertion 3: SpanID zero value is invalid and produces a 16-character zero string.
	var zero trace.SpanID
	if zero.IsValid() {
		fmt.Fprintf(os.Stderr, "FAIL: expected zero SpanID to be invalid\n")
		os.Exit(1)
	}
	if zero.String() != "0000000000000000" {
		fmt.Fprintf(os.Stderr, "FAIL: expected zero SpanID string '0000000000000000', got '%s'\n", zero.String())
		os.Exit(1)
	}

	// Assertion 4: SpanID preserves raw byte array values and formats correctly via String.
	raw := [8]byte{0x00, 0x01, 0x02, 0x03, 0x0a, 0x0b, 0x0e, 0x0f}
	rawSpanID := trace.SpanID(raw)
	if !rawSpanID.IsValid() {
		fmt.Fprintf(os.Stderr, "FAIL: expected rawSpanID with non-zero bytes to be valid\n")
		os.Exit(1)
	}
	if rawSpanID.String() != "000102030a0b0e0f" {
		fmt.Fprintf(os.Stderr, "FAIL: expected String() to be '000102030a0b0e0f', got '%s'\n", rawSpanID.String())
		os.Exit(1)
	}
	if [8]byte(rawSpanID) != raw {
		fmt.Fprintf(os.Stderr, "FAIL: byte representation mismatch\n")
		os.Exit(1)
	}

	// Assertion 5: SpanID MarshalJSON outputs a valid quoted JSON hex string.
	jsonData, err := spanID.MarshalJSON()
	if err != nil {
		fmt.Fprintf(os.Stderr, "FAIL: MarshalJSON returned error: %v\n", err)
		os.Exit(1)
	}
	expectedJSON := fmt.Sprintf("%q", hexStr)
	if string(jsonData) != expectedJSON {
		fmt.Fprintf(os.Stderr, "FAIL: expected JSON %s, got %s\n", expectedJSON, string(jsonData))
		os.Exit(1)
	}

	// Assertion 6: SpanID integrates with SpanContext to identify traces and spans.
	sc := trace.NewSpanContext(trace.SpanContextConfig{
		SpanID: spanID,
	})
	if !sc.HasSpanID() {
		fmt.Fprintf(os.Stderr, "FAIL: expected SpanContext to have SpanID\n")
		os.Exit(1)
	}
	if sc.SpanID() != spanID {
		fmt.Fprintf(os.Stderr, "FAIL: expected SpanContext SpanID '%s', got '%s'\n", spanID.String(), sc.SpanID().String())
		os.Exit(1)
	}

	fmt.Println("PASS: all trace.SpanID contract assertions passed.")
}