go.opentelemetry.io/otel/metric v1.35.0: MeterProvider

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/metric.MeterProvider in pkg:golang/go.opentelemetry.io/otel/metric@v1.35.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/go.opentelemetry.io/otel/metric@v1.35.0
Demonstrate these symbols/APIs:
  - go.opentelemetry.io/otel/metric.MeterProvider
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - 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:sha256:2c8a54fc3bdb4cf9a473699728b6f25b4635956b44047ab46bc693edd83d76f5","contract":["metric.MeterProvider provides access to named Meter instances","Meter creates counter instruments and records measurements","noop.NewMeterProvider satisfies metric.MeterProvider interface"],"goal":"verify go.opentelemetry.io/otel/metric.MeterProvider in pkg:golang/go.opentelemetry.io/otel/metric@v1.35.0","kind":"HOW","packages":["pkg:golang/go.opentelemetry.io/otel/metric@v1.35.0"],"schemaVersion":1,"symbols":["go.opentelemetry.io/otel/metric.MeterProvider"]},"contractCommand":["go","test","./..."],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","language":"go","libc":"glibc","libcVersion":"2.39","moduleSystem":"go.mod","os":"linux","osVersionBucket":"24","packageManager":"go","runtime":"go","runtimeVersion":"1.26","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/go.opentelemetry.io/otel/metric@v1.35.0"],"schemaVersion":1,"subject":"pkg:golang/go.opentelemetry.io/otel/metric@v1.35.0","symbols":["go.opentelemetry.io/otel/metric.MeterProvider"],"verifierAdapter":"golang@1"}

module example.com/meterprovider-sample

go 1.24.0

require go.opentelemetry.io/otel/metric v1.35.0

require go.opentelemetry.io/otel v1.35.0 // 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/go-logr/logr v1.4.2 h1:6pFjapn8bFcIbiKo3XT4j/BhANplGihG6tvd+8rYgrY=
github.com/go-logr/logr v1.4.2/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/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/auto/sdk v1.1.0 h1:cH53jehLUN6UFLY71z+NDOiNJqDdPRaXzTel0sJySYA=
go.opentelemetry.io/auto/sdk v1.1.0/go.mod h1:3wSPjt5PWp2RhlCcmmOial7AvC4DQqZb7a7wCow3W8A=
go.opentelemetry.io/otel v1.35.0 h1:xKWKPxrxB6OtMCbmMY021CqC45J+3Onta9MqjhnusiQ=
go.opentelemetry.io/otel v1.35.0/go.mod h1:UEqy8Zp11hpkUrL73gSlELM0DupHoiq72dR+Zqel/+Y=
go.opentelemetry.io/otel/metric v1.35.0 h1:0znxYu2SNyuMSQT4Y9WDWej0VpcsxkuklLa4/siN90M=
go.opentelemetry.io/otel/metric v1.35.0/go.mod h1:nKVFgxBZ2fReX6IlyW28MgZojkoAkJGaE8CpgeAU3oE=
go.opentelemetry.io/otel/trace v1.35.0 h1:dPpEfJu1sDIqruz7BHFG3c7528f6ddfSWfFDVt/xgMs=
go.opentelemetry.io/otel/trace v1.35.0/go.mod h1:WUk7DtFp1Aw2MkvqGdwiXYDZZNvA/1J8o6xRXLrIkyc=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package sample

import (
	"context"
	"fmt"

	"go.opentelemetry.io/otel/metric"
	"go.opentelemetry.io/otel/metric/noop"
)

// SetupMeter demonstrates creating a Meter from a MeterProvider and creating a counter instrument.
func SetupMeter(mp metric.MeterProvider, meterName string) (metric.Int64Counter, error) {
	if mp == nil {
		mp = noop.NewMeterProvider()
	}
	meter := mp.Meter(meterName)
	counter, err := meter.Int64Counter(
		"sample_requests_total",
		metric.WithDescription("Total number of sample requests"),
		metric.WithUnit("1"),
	)
	if err != nil {
		return nil, fmt.Errorf("failed to create counter: %w", err)
	}
	return counter, nil
}

// RecordEvent records an increment on the provided Int64Counter.
func RecordEvent(ctx context.Context, counter metric.Int64Counter, amount int64) {
	if counter != nil {
		counter.Add(ctx, amount)
	}
}

{
  "schemaVersion": 1,
  "goal": "verify go.opentelemetry.io/otel/metric.MeterProvider in pkg:golang/go.opentelemetry.io/otel/metric@v1.35.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/go.opentelemetry.io/otel/metric@v1.35.0"
  ],
  "symbols": [
    "go.opentelemetry.io/otel/metric.MeterProvider"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "runtime": "node@22.23.2"
  }
}

package test

import (
	"context"
	"testing"

	sample "example.com/meterprovider-sample"
	"go.opentelemetry.io/otel/metric"
	"go.opentelemetry.io/otel/metric/noop"
)

// customMeterProvider embeds noop.MeterProvider to implement metric.MeterProvider
type customMeterProvider struct {
	noop.MeterProvider
	called bool
}

func (c *customMeterProvider) Meter(name string, opts ...metric.MeterOption) metric.Meter {
	c.called = true
	return c.MeterProvider.Meter(name, opts...)
}

func TestMeterProviderContract(t *testing.T) {
	ctx := context.Background()

	// 1. noop.NewMeterProvider satisfies metric.MeterProvider
	noopMP := noop.NewMeterProvider()
	var mp metric.MeterProvider = noopMP

	counter, err := sample.SetupMeter(mp, "example.com/test-meter")
	if err != nil {
		t.Fatalf("unexpected error setting up meter: %v", err)
	}
	if counter == nil {
		t.Fatal("expected non-nil counter")
	}

	// 2. RecordEvent records without panicking or error
	sample.RecordEvent(ctx, counter, 1)

	// 3. Custom struct embedding noop.MeterProvider satisfies metric.MeterProvider
	customMP := &customMeterProvider{
		MeterProvider: noopMP,
	}
	var mp2 metric.MeterProvider = customMP
	counter2, err := sample.SetupMeter(mp2, "example.com/custom-meter")
	if err != nil {
		t.Fatalf("unexpected error setting up custom meter: %v", err)
	}
	if counter2 == nil {
		t.Fatal("expected non-nil counter from custom meter provider")
	}
	if !customMP.called {
		t.Fatal("expected custom MeterProvider.Meter to be called")
	}
}