go.opentelemetry.io/otel/sdk/metric v1.39.0: InstrumentKindCounter

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/sdk/metric.InstrumentKindCounter in pkg:golang/go.opentelemetry.io/otel/sdk/metric@v1.39.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/go.opentelemetry.io/otel/sdk/metric@v1.39.0
Demonstrate these symbols/APIs:
  - go.opentelemetry.io/otel/sdk/metric.InstrumentKindCounter

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:sha256:03e082b74faef91736813bd44e3b01be653cb1d2e9da0782cf6063920a7f7cef","contract":["InstrumentKindCounter is a defined non-zero InstrumentKind constant representing synchronous counter instruments.","InstrumentKindCounter String method returns 'Counter'.","InstrumentKindCounter is distinct from all other defined InstrumentKind constants.","Instrument configured with InstrumentKindCounter matches views selecting for InstrumentKindCounter.","Views configured with InstrumentKindCounter criteria do not match instruments with different kinds."],"goal":"verify go.opentelemetry.io/otel/sdk/metric.InstrumentKindCounter in pkg:golang/go.opentelemetry.io/otel/sdk/metric@v1.39.0","kind":"HOW","packages":["pkg:golang/go.opentelemetry.io/otel/sdk/metric@v1.39.0"],"schemaVersion":1,"symbols":["go.opentelemetry.io/otel/sdk/metric.InstrumentKindCounter"]},"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/sdk/metric@v1.39.0"],"schemaVersion":1,"subject":"pkg:golang/go.opentelemetry.io/otel/sdk/metric@v1.39.0","symbols":["go.opentelemetry.io/otel/sdk/metric.InstrumentKindCounter"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require go.opentelemetry.io/otel/sdk/metric v1.39.0

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 v1.39.0 // indirect
	go.opentelemetry.io/otel/metric v1.39.0 // indirect
	go.opentelemetry.io/otel/sdk v1.39.0 // indirect
	go.opentelemetry.io/otel/trace v1.39.0 // indirect
	golang.org/x/sys v0.39.0 // 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 v1.39.0 h1:8yPrr/S0ND9QEfTfdP9V+SiwT4E0G7Y5MO7p85nis48=
go.opentelemetry.io/otel v1.39.0/go.mod h1:kLlFTywNWrFyEdH0oj2xK0bFYZtHRYUdv1NklR/tgc8=
go.opentelemetry.io/otel/metric v1.39.0 h1:d1UzonvEZriVfpNKEVmHXbdf909uGTOQjA0HF0Ls5Q0=
go.opentelemetry.io/otel/metric v1.39.0/go.mod h1:jrZSWL33sD7bBxg1xjrqyDjnuzTUB0x1nBERXd7Ftcs=
go.opentelemetry.io/otel/sdk v1.39.0 h1:nMLYcjVsvdui1B/4FRkwjzoRVsMK8uL/cj0OyhKzt18=
go.opentelemetry.io/otel/sdk v1.39.0/go.mod h1:vDojkC4/jsTJsE+kh+LXYQlbL8CgrEcwmt1ENZszdJE=
go.opentelemetry.io/otel/sdk/metric v1.39.0 h1:cXMVVFVgsIf2YL6QkRF4Urbr/aMInf+2WKg+sEJTtB8=
go.opentelemetry.io/otel/sdk/metric v1.39.0/go.mod h1:xq9HEVH7qeX69/JnwEfp6fVq5wosJsY1mt4lLfYdVew=
go.opentelemetry.io/otel/trace v1.39.0 h1:2d2vfpEDmCJ5zVYz7ijaJdOF59xLomrvj7bjt6/qCJI=
go.opentelemetry.io/otel/trace v1.39.0/go.mod h1:88w4/PnZSazkGzz/w84VHpQafiU4EtqqlVdxWy+rNOA=
golang.org/x/sys v0.39.0 h1:CvCKL8MeisomCi6qNZ+wbb0DN9E5AATixKsvNtMoMFk=
golang.org/x/sys v0.39.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
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 (
	"context"
	"fmt"

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

func main() {
	kind := metric.InstrumentKindCounter
	fmt.Printf("InstrumentKind: %s (value: %d)\n", kind.String(), kind)

	counterView := metric.NewView(
		metric.Instrument{
			Kind: metric.InstrumentKindCounter,
		},
		metric.Stream{
			Description: "Aggregated counter metric",
		},
	)

	counterInst := metric.Instrument{
		Name: "requests.total",
		Kind: metric.InstrumentKindCounter,
	}
	stream, matched := counterView(counterInst)
	fmt.Printf("Counter matched: %t, Description: %s\n", matched, stream.Description)

	mp := metric.NewMeterProvider(metric.WithView(counterView))
	defer func() {
		_ = mp.Shutdown(context.Background())
	}()

	meter := mp.Meter("sample-meter")
	counter, err := meter.Int64Counter("requests.total")
	if err != nil {
		panic(err)
	}

	counter.Add(context.Background(), 1)
	fmt.Println("Sample executed successfully.")
}

{
  "schemaVersion": 1,
  "goal": "verify go.opentelemetry.io/otel/sdk/metric.InstrumentKindCounter in pkg:golang/go.opentelemetry.io/otel/sdk/metric@v1.39.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/go.opentelemetry.io/otel/sdk/metric@v1.39.0"
  ],
  "symbols": [
    "go.opentelemetry.io/otel/sdk/metric.InstrumentKindCounter"
  ]
}

package main

import (
	"fmt"
	"os"

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

func main() {
	// Assertion 1: InstrumentKindCounter is a defined non-zero InstrumentKind constant representing synchronous counter instruments.
	kind := metric.InstrumentKindCounter
	if kind == 0 {
		fmt.Fprintf(os.Stderr, "FAIL: expected InstrumentKindCounter to be non-zero\n")
		os.Exit(1)
	}

	// Assertion 2: InstrumentKindCounter String method returns 'Counter'.
	if kindStr := kind.String(); kindStr != "Counter" {
		fmt.Fprintf(os.Stderr, "FAIL: expected String() to return 'Counter', got '%s'\n", kindStr)
		os.Exit(1)
	}

	// Assertion 3: InstrumentKindCounter is distinct from all other defined InstrumentKind constants.
	otherKinds := []metric.InstrumentKind{
		metric.InstrumentKindUpDownCounter,
		metric.InstrumentKindHistogram,
		metric.InstrumentKindObservableCounter,
		metric.InstrumentKindObservableUpDownCounter,
		metric.InstrumentKindObservableGauge,
		metric.InstrumentKindGauge,
	}
	for _, other := range otherKinds {
		if kind == other {
			fmt.Fprintf(os.Stderr, "FAIL: InstrumentKindCounter must not equal %v\n", other)
			os.Exit(1)
		}
	}

	// Assertion 4: Instrument configured with InstrumentKindCounter matches views selecting for InstrumentKindCounter.
	customDesc := "Count of processed requests"
	view := metric.NewView(
		metric.Instrument{Kind: metric.InstrumentKindCounter},
		metric.Stream{Description: customDesc},
	)
	matchedStream, matched := view(metric.Instrument{
		Name: "requests_total",
		Kind: metric.InstrumentKindCounter,
	})
	if !matched {
		fmt.Fprintf(os.Stderr, "FAIL: expected view to match Instrument with InstrumentKindCounter\n")
		os.Exit(1)
	}
	if matchedStream.Description != customDesc {
		fmt.Fprintf(os.Stderr, "FAIL: expected stream description '%s', got '%s'\n", customDesc, matchedStream.Description)
		os.Exit(1)
	}

	// Assertion 5: Views configured with InstrumentKindCounter criteria do not match instruments with different kinds.
	nonCounterKinds := []metric.InstrumentKind{
		metric.InstrumentKindHistogram,
		metric.InstrumentKindUpDownCounter,
		metric.InstrumentKindGauge,
	}
	for _, nonCounter := range nonCounterKinds {
		_, matchedNonCounter := view(metric.Instrument{
			Name: "other_metric",
			Kind: nonCounter,
		})
		if matchedNonCounter {
			fmt.Fprintf(os.Stderr, "FAIL: view with InstrumentKindCounter criteria should not match kind %v\n", nonCounter)
			os.Exit(1)
		}
	}

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